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2526121
10.1007/s00023-005-0219-7
Casimir effect, in a broad interpretation which we adopt here, consists in a backreaction of a quantum system to adiabatically changing external conditions. Although the system is usually taken to be a quantum field, we show that this restriction rather blurs than helps to clarify the statement of the problem. We discuss the problem from the point of view of algebraic structure of quantum theory, which is most appropriate in this context. The system in question may be any quantum system, among others both finite as infinite dimensional canonical systems are allowed. A simple finite-dimensional model is discussed. We identify precisely the source of difficulties and infinities in most of traditional treatments of the problem for infinite dimensional systems (such as quantum fields), which is incompatibility of algebras of observables or their representations. We formulate conditions on model idealizations which are acceptable for the discussion of the adiabatic backreaction problem. In the case of quantum field models in that class we find that the normal ordered energy density is a well defined distribution, yielding global energy in the limit of a unit test function. Although we see the "zero point" expressions as inappropriate, we show how they can arise in the quantum field theory context as a result of uncontrollable manipulations.Comment: 40 pages, AMS-LaTeX; to appear in Ann. H. Poincar
Quantum backreaction (Casimir) effect I. What are admissible idealizations?
quantum backreaction (casimir) effect i. what are admissible idealizations?
casimir broad adopt backreaction adiabatically changing conditions. restriction blurs helps clarify statement problem. algebraic context. infinite canonical allowed. discussed. precisely difficulties infinities traditional treatments infinite incompatibility algebras observables representations. formulate idealizations acceptable adiabatic backreaction problem. ordered yielding function. expressions inappropriate arise uncontrollable pages latex ann. poincar
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2526049
10.1007/s00023-005-0226-8
The universal covering of SO(3) is modelled as a reflection group G_R in a representation independent fashion. For relativistic quantum fields, the Unruh effect of vacuum states is known to imply an intrinsic form of reflection symmetry, which is referred to as "modular P_1CT-symmetry (Bisognano, Wichmann, 1975, 1976, and Guido, Longo, [funct-an/9406005]). This symmetry is used to construct a representation of G_R by pairs of modular P_1CT-operators. The representation thus obtained satisfies Pauli's spin-statistics relation.Comment: Accepted for publication in Ann. H. Poincare, (annoying) misprints correcte
Spin, Statistics, and Reflections, I. Rotation Invariance
spin, statistics, and reflections, i. rotation invariance
universal covering modelled reflection fashion. relativistic unruh imply intrinsic reflection referred modular bisognano wichmann guido longo funct modular operators. satisfies pauli publication ann. poincare annoying misprints correcte
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2556096
10.1007/s00023-005-0229-5
We prove the property of stochastic stability previously introduced as a consequence of the (unproved) continuity hypothesis in the temperature of the spin-glass quenched state. We show that stochastic stability holds in beta-average for both the Sherrington-Kirkpatrick model in terms of the square of the overlap function and for the Edwards-Anderson model in terms of the bond overlap. We show that the volume rate at which the property is reached in the thermodynamic limit is V^{-1}. As a byproduct we show that the stochastic stability identities coincide with those obtained with a different method by Ghirlanda and Guerra when applyed to the thermal fluctuations only.Comment: 12 pages, revised versio
Spin-Glass Stochastic Stability: a Rigorous Proof
spin-glass stochastic stability: a rigorous proof
stochastic unproved continuity glass quenched state. stochastic beta sherrington kirkpatrick overlap edwards anderson bond overlap. reached thermodynamic byproduct stochastic identities coincide ghirlanda guerra applyed pages revised versio
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2555990
10.1007/s00023-005-0231-y
We study non--adiabatic transitions in scattering theory for the time dependent molecular Schroedinger equation in the Born--Oppenheimer limit. We assume the electron Hamiltonian has finitely many levels and consider the propagation of coherent states with high enough total energy. When two of the electronic levels are isolated from the rest of the electron Hamiltonian's spectrum and display an avoided crossing, we compute the component of the nuclear wave function associated with the non--adiabatic transition that is generated by propagation through the avoided crossing. This component is shown to be exponentially small in the square of the Born--Oppenheimer parameter, due to the Landau-Zener mechanism. It propagates asymptotically as a free Gaussian in the nuclear variables, and its momentum is shifted. The total transition probability for this transition and the momentum shift are both larger than what one would expect from a naive approximation and energy conservation
Determination of Non-Adiabatic Scattering Wave Functions in a Born-Oppenheimer Model
determination of non-adiabatic scattering wave functions in a born-oppenheimer model
adiabatic schroedinger born oppenheimer limit. finitely propagation coherent energy. display avoided crossing adiabatic propagation avoided crossing. exponentially born oppenheimer landau zener mechanism. propagates asymptotically shifted. naive conservation
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2526222
10.1007/s00023-005-0232-x
We work out the general features of perturbative field theory on noncommutative manifolds defined by isospectral deformation. These (in general curved) `quantum spaces', generalizing Moyal planes and noncommutative tori, are constructed using Rieffel's theory of deformation quantization for action of $\R^l$. Our framework, incorporating background field methods and tools of QFT in curved spaces, allows to deal both with compact and non-compact spaces, as well as with periodic or not deformations, essentially in the same way. We compute the quantum effective action up to one loop for a scalar theory, showing the different UV/IR mixing phenomena for different kinds of isospectral deformations. The presence and behavior of the non-planar parts of the Green functions is understood simply in terms of off-diagonal heat kernel contributions. For periodic deformations, a Diophantine condition on the noncommutativity parameters is found to play a role in the analytical nature of the non-planar part of the one-loop reduced effective action. Existence of fixed points for the action may give rise to a new kind of UV/IR mixing.Comment: 30 pages, no figure, version
Heat-Kernel Approach to UV/IR Mixing on Isospectral Deformation Manifolds
heat-kernel approach to uv/ir mixing on isospectral deformation manifolds
perturbative noncommutative manifolds isospectral deformation. curved generalizing moyal planes noncommutative tori rieffel deformation quantization incorporating curved deal deformations essentially way. phenomena kinds isospectral deformations. planar understood diagonal kernel contributions. deformations diophantine noncommutativity planar action. kind pages
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2431855
10.1007/s00023-005-0235-7
We prove that "first singularities" in the non-trapped region of the maximal development of spherically symmetric asymptotically flat data for the Einstein-Vlasov system must necessarily emanate from the center. The notion of "first" depends only on the causal structure and can be described in the language of terminal indecomposable pasts (TIPs). This result suggests a local approach to proving weak cosmic censorship for this system. It can also be used to give the first proof of the formation of black holes by the collapse of collisionless matter from regular initial configurations.Comment: 19 pages, 2 figure
An extension principle for the Einstein-Vlasov system in spherical symmetry
an extension principle for the einstein-vlasov system in spherical symmetry
singularities trapped maximal spherically asymptotically einstein vlasov necessarily emanate center. notion causal indecomposable pasts tips proving cosmic censorship system. holes collapse collisionless pages
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2556723
10.1007/s00023-005-0243-7
Although many physical arguments account for using a modified definition of time delay in multichannel-type scattering processes, one can hardly find rigorous results on that issue in the literature. We try to fill in this gap by showing, both in an abstract setting and in a short-range case, the identity of the modified time delay and the Eisenbud-Wigner time delay in waveguides. In the short-range case we also obtain limiting absorption principles, state spectral properties of the total Hamiltonian, prove the existence of the wave operators and show an explicit formula for the S-matrix. The proofs rely on stationary and commutator methods
Time delay and short-range scattering in quantum waveguides
time delay and short-range scattering in quantum waveguides
arguments delay multichannel hardly rigorous literature. fill delay eisenbud wigner delay waveguides. limiting principles matrix. proofs rely stationary commutator
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2588047
10.1007/s00023-005-0244-6
Model sets are always Meyer sets, but not vice-versa. This article is about characterizing model sets (general and regular) amongst the Meyer sets in terms of two associated dynamical systems. These two dynamical systems describe two very different topologies on point sets, one local and one global. In model sets these two are strongly interconnected and this connection is essentially definitive. The paper is set in the context of multi-colour sets, that is to say, point sets in which points come in a finite number of colours, that are loosely coupled together by finite local complexity.Comment: 23pages; to appear in Annales Henri Poincar
A Characterization of Model Multi-colour Sets
a characterization of model multi-colour sets
meyer vice versa. characterizing amongst meyer systems. topologies global. interconnected connection essentially definitive. colour come colours loosely pages annales henri poincar
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2556649
10.1007/s00023-005-0248-2
The relativistic Vlasov-Maxwell system of plasma physics is considered with initial data on a past light cone. This characteristic initial value problem arises in a natural way as a mathematical framework to study the existence of solutions isolated from incoming radiation. Various consequences of the mass-energy conservation and of the absence of incoming radiation condition are first derived assuming the existence of global smooth solutions. In the spherically symmetric case, the existence of a unique classical solution in the future of the initial cone follows by arguments similar to the case of initial data at time $t=0$. The total mass-energy of spherically symmetric solutions equals the (properly defined) mass-energy on backward and forward light cones.Comment: 16 pages. Version in pres
On a characteristic initial value problem in Plasma physics
on a characteristic initial value problem in plasma physics
relativistic vlasov maxwell cone. arises mathematical incoming radiation. consequences conservation incoming solutions. spherically cone arguments spherically equals properly backward pages. pres
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2527876
10.1007/s00023-005-0249-1
Casimir effect in most general terms may be understood as a backreaction of a quantum system causing an adiabatic change of the external conditions under which it is placed. This paper is the second installment of a work scrutinizing this effect with the use of algebraic methods in quantum theory. The general scheme worked out in the first part is applied here to the discussion of particular models. We consider models of the quantum scalar field subject to external interaction with ``softened'' Dirichlet or Neumann boundary conditions on two parallel planes. We show that the case of electromagnetic field with softened perfect conductor conditions on the planes may be reduced to the other two. The ``softening'' is implemented on the level of the dynamics, and is not imposed ad hoc, as is usual in most treatments, on the level of observables. We calculate formulas for the backreaction energy in these models. We find that the common belief that for electromagnetic field the backreaction force tends to the strict Casimir formula in the limit of ``removed cutoff'' is not confirmed by our strict analysis. The formula is model dependent and the Casimir value is merely a term in the asymptotic expansion of the formula in inverse powers of the distance of the planes. Typical behaviour of the energy for large separation of the plates in the class of models considered is a quadratic fall-of. Depending on the details of the ``softening'' of the boundary conditions the backreaction force may become repulsive for large separations.Comment: 50 pages, AMS-LaTeX; to appear in Ann. H. Poincar
Quantum backreaction (Casimir) effect. II. Scalar and electromagnetic fields
quantum backreaction (casimir) effect. ii. scalar and electromagnetic fields
casimir understood backreaction causing adiabatic placed. installment scrutinizing algebraic theory. worked models. softened dirichlet neumann planes. electromagnetic softened perfect conductor planes two. softening implemented imposed usual treatments observables. formulas backreaction models. belief electromagnetic backreaction tends strict casimir removed cutoff confirmed strict analysis. casimir merely asymptotic powers planes. plates quadratic fall softening backreaction repulsive pages latex ann. poincar
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2556969
10.1007/s00023-005-0251-7
We consider an electrically charged particle on the Euclidean plane subjected to a perpendicular magnetic field which depends only on one of the two Cartesian co-ordinates. For such a ``unidirectionally constant'' magnetic field (UMF), which otherwise may be random or not, we prove certain spectral and transport properties associated with the corresponding one-particle Schroedinger operator (without scalar potential) by analysing its ``energy-band structure''. In particular, for an ergodic random UMF we provide conditions which ensure that the operator's entire spectrum is almost surely absolutely continuous. This implies that, along the direction in which the random UMF is constant, the quantum-mechanical motion is almost surely ballistic, while in the perpendicular direction in the plane one has dynamical localisation. The conditions are verified, for example, for Gaussian and Poissonian random UMF's with non-zero mean-values. These results may be viewed as ``random analogues'' of results first obtained by A. Iwatsuka [Publ. RIMS, Kyoto Univ. 21 (1985) 385] and (non-rigorously) by J. E. Mueller [Phys. Rev. Lett. 68 (1992) 385]
Energetic and dynamic properties of a quantum particle in a spatially random magnetic field with constant correlations along one direction
energetic and dynamic properties of a quantum particle in a spatially random magnetic field with constant correlations along one direction
electrically euclidean subjected perpendicular cartesian ordinates. unidirectionally schroedinger analysing ergodic ensure surely absolutely continuous. surely ballistic perpendicular localisation. verified poissonian values. viewed analogues iwatsuka publ. rims kyoto univ. rigorously mueller phys. rev. lett.
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2380026
10.1007/s00023-005-0254-4
We establish a correspondence between polynomial representations of the Temperley and Lieb algebra and certain deformations of the Quantum Hall Effect wave functions. When the deformation parameter is a third root of unity, the representation degenerates and the wave functions coincide with the domain wall boundary condition partition function appearing in the conjecture of A.V. Razumov and Y.G. Stroganov. In particular, this gives a proof of the identification of the sum of the entries of a O(n) transfer matrix eigenvector and a six vertex-model partition function, alternative to that of P. Di Francesco and P. Zinn-Justin.Comment: latex ihp.tex, 2 files, 1 figure, 28 pages (http://www-spht.cea.fr/articles/T05/087
Quantum incompressibility and Razumov Stroganov type conjectures
quantum incompressibility and razumov stroganov type conjectures
establish correspondence representations temperley lieb deformations hall functions. deformation unity degenerates coincide partition appearing conjecture a.v. razumov y.g. stroganov. entries eigenvector partition francesco zinn latex ihp.tex files pages
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2556997
10.1007/s00023-005-0261-5
We study the perturbation of bound states embedded in the continuous spectrum which are unstable by the Fermi Golden Rule. The approach to resonance theory based on spectral deformation is extended to a more general class of quantum systems characterized by Mourre's inequality and smoothness of the resolvent. Within the framework of perturbation theory it is still possible to give a definite meaning to the notion of complex resonance energies and of corresponding metastable states. The main result is a quasi-exponential decay estimate up to a controlled error of higher order in perturbation theory.Comment: 17 page
A general resonance theory based on Mourre's inequality
a general resonance theory based on mourre's inequality
perturbation embedded unstable fermi golden rule. deformation mourre inequality smoothness resolvent. perturbation definite meaning notion metastable states. quasi exponential perturbation
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2556620
10.1007/s00023-006-0263-y
We study the motion of solitary-wave solutions of a family of focusing generalized nonlinear Schroedinger equations with a confining, slowly varying external potential, $V(x)$. A Lyapunov-Schmidt decomposition of the solution combined with energy estimates allows us to control the motion of the solitary wave over a long, but finite, time interval. We show that the center of mass of the solitary wave follows a trajectory close to that of a Newtonian point particle in the external potential $V(x)$ over a long time interval.Comment: 42 pages, 2 figure
Long time motion of NLS solitary waves in a confining potential
long time motion of nls solitary waves in a confining potential
solitary focusing schroedinger confining slowly lyapunov schmidt decomposition solitary interval. solitary trajectory newtonian pages
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2662757
10.1007/s00023-006-0269-5
We derive for Bohmian mechanics topological factors for quantum systems with a multiply-connected configuration space Q. These include nonabelian factors corresponding to what we call holonomy-twisted representations of the fundamental group of Q. We employ wave functions on the universal covering space of Q. As a byproduct of our analysis, we obtain an explanation, within the framework of Bohmian mechanics, of the fact that the wave function of a system of identical particles is either symmetric or anti-symmetric.Comment: 17 pages, no figure
Topological Factors Derived From Bohmian Mechanics
topological factors derived from bohmian mechanics
derive bohmian mechanics topological multiply nonabelian call holonomy twisted representations employ universal covering byproduct explanation bohmian mechanics pages
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2557420
10.1007/s00023-006-0272-x
We consider a family of non-compact manifolds $X_\eps$ (``graph-like manifolds'') approaching a metric graph $X_0$ and establish convergence results of the related natural operators, namely the (Neumann) Laplacian $\laplacian {X_\eps}$ and the generalised Neumann (Kirchhoff) Laplacian $\laplacian {X_0}$ on the metric graph. In particular, we show the norm convergence of the resolvents, spectral projections and eigenfunctions. As a consequence, the essential and the discrete spectrum converge as well. Neither the manifolds nor the metric graph need to be compact, we only need some natural uniformity assumptions. We provide examples of manifolds having spectral gaps in the essential spectrum, discrete eigenvalues in the gaps or even manifolds approaching a fractal spectrum. The convergence results will be given in a completely abstract setting dealing with operators acting in different spaces, applicable also in other geometric situations.Comment: some references added, still 36 pages, 4 figure
Spectral convergence of non-compact quasi-one-dimensional spaces
spectral convergence of non-compact quasi-one-dimensional spaces
manifolds manifolds approaching establish neumann laplacian laplacian generalised neumann kirchhoff laplacian laplacian graph. norm resolvents projections eigenfunctions. converge well. neither manifolds uniformity assumptions. manifolds gaps eigenvalues gaps manifolds approaching fractal spectrum. dealing acting applicable geometric pages
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2587514
10.1007/s00023-006-0274-8
We study Hilbert space aspects of the Klein-Gordon equation in two-dimensional spacetime. We associate to its restriction to a spacelike wedge a scattering from the past light cone to the future light cone, which is then shown to be (essentially) the Hankel transform of order zero. We apply this to give a novel proof, solely based on the causality of this spatio-temporal wave propagation, of the theorem of de Branges and V. Rovnyak concerning Hankel pairs with a support property. We recover their isometric expansion as an application of Riemann's general method for solving Cauchy-Goursat problems of hyperbolic type.Comment: 24 pages. Final ms, to appear. Improvements on pages 8 and 9, and 15-1
Spacetime causality in the study of the Hankel transform
spacetime causality in the study of the hankel transform
hilbert klein gordon spacetime. associate restriction spacelike wedge cone cone essentially hankel transform zero. solely causality spatio propagation branges rovnyak concerning hankel property. recover isometric riemann solving cauchy goursat hyperbolic pages. appear. improvements pages
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2556656
10.1007/s00023-006-0277-5
We study the semiclassical behaviour of eigenfunctions of quantum systems with ergodic classical limit. By the quantum ergodicity theorem almost all of these eigenfunctions become equidistributed in a weak sense. We give a simple derivation of an upper bound of order $\abs{\ln\hbar}^{-1}$ on the rate of quantum ergodicity if the classical system is ergodic with a certain rate. In addition we obtain a similar bound on transition amplitudes if the classical system is weak mixing. Both results generalise previous ones by Zelditch. We then extend the results to some classes of quantised maps on the torus and obtain a logarithmic rate for perturbed cat-maps and a sharp algebraic rate for parabolic maps.Comment: 18 page
Upper bounds on the rate of quantum ergodicity
upper bounds on the rate of quantum ergodicity
semiclassical eigenfunctions ergodic limit. ergodicity eigenfunctions equidistributed sense. derivation hbar ergodicity ergodic rate. amplitudes mixing. generalise zelditch. extend quantised torus logarithmic perturbed sharp algebraic parabolic
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2557376
10.1007/s00023-006-0280-x
We consider the N-site U_{q}(gl(N)) integrable spin chain with periodic and open diagonal soliton-preserving boundary conditions. By employing analytical Bethe ansatz techniques we are able to determine the spectrum and the corresponding Bethe ansatz equations for the general case, where each site of the spin chain is associated to any representation of U_{q}(gl(N)). In the case of open spin chain, we study finite dimensional representations of the quantum reflection algebra, and prove in full generality that the pseudo-vacuum is a highest weight of the monodromy matrix. For these two types of spin chain, we study the (generalized) "algebraic" fusion procedures, which amount to construct the quantum contraction and the Sklyanin determinant for the affine U_{q}(gl(N)) and quantum reflection algebras. We also determine the symmetry algebra of these two types of spin chains, including general K and K^+ diagonal matrices for the open case. The case of open spin chains with soliton non-preserving boundary conditions is also presented in the framework of quantum twisted Yangians. The symmetry algebra of this spin chains is studied. We also give an exhaustive classification of the invertible matricial solutions to the corresponding reflection equation.Comment: 48 pages; Bounds on parameters Mj corrected; References added; Examples adde
Spectrum and Bethe ansatz equations for the U_ {q}(gl(N)) closed and open spin chains in any representation
spectrum and bethe ansatz equations for the u_ {q}(gl(n)) closed and open spin chains in any representation
integrable diagonal soliton preserving conditions. employing bethe ansatz bethe ansatz representations reflection generality pseudo monodromy matrix. algebraic fusion contraction sklyanin determinant affine reflection algebras. chains diagonal case. chains soliton preserving twisted yangians. chains studied. exhaustive invertible matricial reflection pages bounds corrected adde
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2588785
10.1007/s00023-006-0281-9
We study the Yangians Y(a) associated with the simple Lie algebras a of type B, C or D. The algebra Y(a) can be regarded as a quotient of the extended Yangian X(a) whose defining relations are written in an R-matrix form. In this paper we are concerned with the algebraic structure and representations of the algebra X(a). We prove an analog of the Poincare-Birkhoff-Witt theorem for X(a) and show that the Yangian Y(a) can be realized as a subalgebra of X(a). Furthermore, we give an independent proof of the classification theorem for the finite-dimensional irreducible representations of X(a) which implies the corresponding theorem of Drinfeld for the Yangians Y(a). We also give explicit constructions for all fundamental representation of the Yangians.Comment: 65 page
On the R-matrix realization of Yangians and their representations
on the r-matrix realization of yangians and their representations
yangians algebras regarded quotient yangian defining form. concerned algebraic representations analog poincare birkhoff witt yangian realized subalgebra irreducible representations drinfeld yangians constructions
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2590425
10.1007/s00023-006-0283-7
The exotic bialgebra S03, defined by a solution of the Yang-Baxter equation, which is not a deformation of the trivial, is considered. Its FRT dual algebra $s03_F$ is studied. The Baxterisation of the dual algebra is given in two different parametrisations. The finite-dimensional representations of $s03_F$ are considered. Diagonalisations of the braid matrices are used to yield remarkable insights concerning representations of the L-algebra and to formulate the fusion of finite-dimensional representations. Possible applications are considered, in particular, an exotic eight-vertex model and an integrable spin-chain model.Comment: 24 pages, Latex; V2: revised subsection 4.1, added 9 references, to appear in Annales Henri Poincare in the volume dedicated to D. Arnaudo
Exotic Bialgebra S03: Representations, Baxterisation and Applications
exotic bialgebra s03: representations, baxterisation and applications
exotic bialgebra baxter deformation trivial considered. studied. baxterisation parametrisations. representations considered. diagonalisations braid remarkable insights concerning representations formulate fusion representations. exotic eight integrable pages latex revised subsection annales henri poincare dedicated arnaudo
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2529065
10.1007/s00023-006-0284-6
The method of bosonization is extended to the case when a dissipationless point-like defect is present in space-time. Introducing the chiral components of a massless scalar field, interacting with the defect in two dimensions, we construct the associated vertex operators. The main features of the corresponding vertex algebra are established. As an application of this framework we solve the massless Thirring model with defect. We also construct the vertex representation of the sl(2) Kac-Moody algebra, describing the complex interplay between the left and right sectors due to the interaction with the defect. The Sugawara form of the energy-momentum tensor is also explored.Comment: 23 pages, 1 figur
Bosonization and Vertex Algebras with Defects
bosonization and vertex algebras with defects
bosonization dissipationless defect time. introducing chiral massless interacting defect operators. established. solve massless thirring defect. moody describing interplay sectors defect. sugawara pages figur
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2529881
10.1007/s00023-006-0287-3
Bound state excitations of the spin 1/2-XYZ model are considered inside the Bethe Ansatz framework by exploiting the equivalent Non-Linear Integral Equations. Of course, these bound states go to the sine-Gordon breathers in the suitable limit and therefore the scattering factors between them are explicitly computed by inspecting the corresponding Non-Linear Integral Equations. As a consequence, abstracting from the physical model the Zamolodchikov-Faddeev algebra of two $n$-th elliptic breathers defines a tower of $n$-order Deformed Virasoro Algebras, reproducing the $n=1$ case the usual well-known algebra of Shiraishi-Kubo-Awata-Odake \cite{SKAO}.Comment: Latex version, 13 page
The elliptic scattering theory of the 1/2-XYZ and higher order Deformed Virasoro Algebras
the elliptic scattering theory of the 1/2-xyz and higher order deformed virasoro algebras
excitations bethe ansatz exploiting equations. sine gordon breathers explicitly inspecting equations. abstracting zamolodchikov faddeev elliptic breathers defines tower deformed virasoro algebras reproducing usual shiraishi kubo awata odake cite skao .comment latex
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2386924
10.1007/s00023-006-0290-8
We discuss irreducible highest weight representations of the sl(2) loop algebra and reducible indecomposable ones in association with the sl(2) loop algebra symmetry of the six-vertex model at roots of unity. We formulate an elementary proof that every highest weight representation with distinct evaluation parameters is irreducible. We present a general criteria for a highest weight representation to be irreducble. We also give an example of a reducible indecomposable highest weight representation and discuss its dimensionality.Comment: 10 pages, no figures, submitted to the proceedings of the international workshop ``Recent Advances in Quantum Integrable Systems'', September 6-9, 2005, LAPTH, Annecy-le-Vieux, Franc
The six-vertex model at roots of unity and some highest weight representations of the sl(2) loop algebra
the six-vertex model at roots of unity and some highest weight representations of the sl(2) loop algebra
irreducible representations reducible indecomposable roots unity. formulate elementary irreducible. irreducble. reducible indecomposable pages submitted workshop advances integrable september lapth annecy vieux franc
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2583678
10.1007/s00023-006-0292-6
The matrix elements of the $2\times 2$ fusion of Baxter's elliptic $R$-matrix, $R^{(2,2)}(u)$, are given explicitly. Based on a note by Jimbo, we give a formula which show that $R^{(2,2)}(u)$ is gauge equivalent to Fateev's $R$-matrix for the 21-vertex model. Then the crossing symmetry formula for $R^{(2,2)}(u)$ is derived. We also consider the fusion of the vertex-face correspondence relation and derive a crossing symmetry relation between the fusion of the intertwining vectors and their dual vectors.Comment: To appear in the proceedings of the workshop ``Solvable Lattice Models 2004", July 20--23, 2004, RIMS Koukyuroku, Kyoto Universit
Fusion of Baxter's Elliptic $R$-matrix and the Vertex-Face Correspondence
fusion of baxter's elliptic $r$-matrix and the vertex-face correspondence
fusion baxter elliptic explicitly. jimbo fateev model. crossing derived. fusion correspondence derive crossing fusion intertwining workshop solvable rims koukyuroku kyoto universit
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2393251
10.1007/s00023-006-0294-4
The spin-1/2 zig-zag Heisenberg ladder (J_1 - J_2 model) is considered. A new representation for the model is found and a saddle point approximation over the spin-liquid order parameter < \vec \sigma_{n-1}(\vec \sigma_{n}\times \vec \sigma_{n+1}) > is performed. Corresponding effective action is derived and analytically analyzed. We observe the presence of phase transitions at values J_2/J_1=0.231 and J_2/J_1=1/2.Comment: 12 pages, 6 figures. Contribution to the Annales Henri Poincare volume dedicated to the memory of Daniel Arnaudo
Mean-field theory for Heisenberg zigzag ladder: Ground state energy and spontaneous symmetry breaking
mean-field theory for heisenberg zigzag ladder: ground state energy and spontaneous symmetry breaking
heisenberg ladder considered. saddle sigma sigma sigma performed. analytically analyzed. pages figures. annales henri poincare dedicated daniel arnaudo
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2388837
10.1007/s00023-006-0295-3
The two-site Bose--Hubbard model is a simple model used to study Josephson tunneling between two Bose--Einstein condensates. In this work we give an overview of some mathematical aspects of this model. Using a classical analysis, we study the equations of motion and the level curves of the Hamiltonian. Then, the quantum dynamics of the model is investigated using direct diagonalisation of the Hamiltonian. In both of these analyses, the existence of a threshold coupling between a delocalised and a self-trapped phase is evident, in qualitative agreement with experiments. We end with a discussion of the exact solvability of the model via the algebraic Bethe ansatz.Comment: 10 pages, 5 figures, submitted for publication in Annales Henri Poincar
The two-site Bose--Hubbard model
the two-site bose--hubbard model
bose hubbard josephson tunneling bose einstein condensates. overview mathematical model. hamiltonian. diagonalisation hamiltonian. delocalised trapped evident qualitative experiments. solvability algebraic bethe pages submitted publication annales henri poincar
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2557767
10.1007/s00023-006-0297-1
We study the higher-order correlation functions of covariant families of observables associated with random Schr\"odinger operators on the lattice in the strong disorder regime. We prove that if the distribution of the random variables has a density analytic in a strip about the real axis, then these correlation functions are analytic functions of the energy outside of the planes corresponding to coincident energies. In particular, this implies the analyticity of the density of states, and of the current-current correlation function outside of the diagonal. Consequently, this proves that the current-current correlation function has an analytic density outside of the diagonal at strong disorder
Smoothness of Correlations in the Anderson Model at Strong Disorder
smoothness of correlations in the anderson model at strong disorder
covariant families observables schr odinger disorder regime. analytic strip analytic planes coincident energies. analyticity diagonal. proves analytic diagonal disorder
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2590139
10.1007/s00023-006-0300-x
We study extreme values of desymmetrized eigenfunctions (so called Hecke eigenfunctions) for the quantized cat map, a quantization of a hyperbolic linear map of the torus. In a previous paper it was shown that for prime values of the inverse Planck constant N=1/h, such that the map is diagonalizable (but not upper triangular) modulo N, the Hecke eigenfunctions are uniformly bounded. The purpose of this paper is to show that the same holds for any prime N provided that the map is not upper triangular modulo N. We also find that the supremum norms of Hecke eigenfunctions are << N^epsilon for all epsilon>0 in the case of N square free.Comment: 16 pages. Introduction expanded; comparison with supremum norms of eigenfunctions of the Laplacian added. Bound for square free N adde
Bounds on supremum norms for Hecke eigenfunctions of quantized cat maps
bounds on supremum norms for hecke eigenfunctions of quantized cat maps
extreme desymmetrized eigenfunctions hecke eigenfunctions quantized quantization hyperbolic torus. prime planck diagonalizable triangular modulo hecke eigenfunctions uniformly bounded. prime triangular modulo supremum norms hecke eigenfunctions epsilon epsilon pages. expanded supremum norms eigenfunctions laplacian added. adde
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2557805
10.1007/s00023-006-0302-8
We analyze Schr\"odinger operators whose potential is given by a singular interaction supported on a sub-manifold of the ambient space. Under the assumption that the operator has at least two eigenvalues below its essential spectrum we derive estimates on the lowest spectral gap. In the case where the sub-manifold is a finite curve in two dimensional Euclidean space the size of the gap depends only on the following parameters: the length, diameter and maximal curvature of the curve, a certain parameter measuring the injectivity of the curve embedding, and a compact sub-interval of the open, negative energy half-axis which contains the two lowest eigenvalues.Comment: 24 pages. To appear in slightly different form in Annales Henri Poincar
Lower bounds on the lowest spectral gap of singular potential Hamiltonians
lower bounds on the lowest spectral gap of singular potential hamiltonians
analyze schr odinger singular manifold ambient space. eigenvalues derive gap. manifold euclidean maximal curvature measuring injectivity embedding pages. annales henri poincar
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52455389
10.1007/s00023-006-0308-2
International audienceThe Fourier transform of orthogonal polynomials with respect to their own orthogonality measure defines the family of Fourier-Bessel functions. We study the asymptotic behaviour of these functions and of their products, for large real values of the argument. By employing a Mellin analysis we construct a general framework to exhibit the relation of the asymptotic decay laws to certain dimensions of the orthogonality measure, that are defined via the divergence abscissas of suitable integrals. The unifying rôle of Mellin transform techniques in deriving classical and new results is underlined
The Asymptotic Behaviour of the Fourier Transforms of Orthogonal Polynomials I: Mellin Transform Techniques
the asymptotic behaviour of the fourier transforms of orthogonal polynomials i: mellin transform techniques
audiencethe fourier transform orthogonal polynomials orthogonality defines fourier bessel functions. asymptotic argument. employing mellin exhibit asymptotic laws orthogonality divergence abscissas integrals. unifying rôle mellin transform deriving underlined
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2590493
10.1007/s00023-006-0311-7
We relate two types of phase space distributions associated to eigenfunctions $\phi_{ir_j}$ of the Laplacian on a compact hyperbolic surface $X_{\Gamma}$: (1) Wigner distributions $\int_{S^*\X} a dW_{ir_j}=< Op(a)\phi_{ir_j}, \phi_{ir_j}>_{L^2(\X)}$, which arise in quantum chaos. They are invariant under the wave group. (2) Patterson-Sullivan distributions $PS_{ir_j}$, which are the residues of the dynamical zeta-functions $\lcal(s; a): = \sum_\gamma \frac{e^{-sL_\gamma}}{1-e^{-L_\gamma}} \int_{\gamma_0} a$ (where the sum runs over closed geodesics) at the poles $s = {1/2} + ir_j$. They are invariant under the geodesic flow. We prove that these distributions (when suitably normalized) are asymptotically equal as $r_j \to \infty$. We also give exact relations between them. This correspondence gives a new relation between classical and quantum dynamics on a hyperbolic surface, and consequently a formulation of quantum ergodicity in terms of classical ergodic theory.Comment: 54 pages, no figures. Added some reference
Patterson-Sullivan distributions and quantum ergodicity
patterson-sullivan distributions and quantum ergodicity
relate eigenfunctions laplacian hyperbolic gamma wigner arise chaos. group. patterson sullivan zeta lcal gamma frac gamma gamma gamma runs geodesics poles geodesic flow. suitably asymptotically infty them. correspondence hyperbolic formulation ergodicity ergodic pages figures.
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2591533
10.1007/s00023-006-0313-5
This work results from our attempts to solve Boltzmann-Sinai's hypothesis about the ergodicity of hard ball gases. A crucial element in the studies of the dynamics of hard balls is the analysis of special hypersurfaces in the phase space consisting of degenerate trajectories (which lack complete hyperbolicity). We prove that if a flow-invariant hypersurface $J$ in the phase space of a semi-dispersing billiard has a negative Lyapunov function, then the volume of the forward image of $J$ grows at least linearly in time. Our proof is independent of the solution of the Boltzmann-Sinai hypothesis, and we provide a complete and self-contained argument here
Flow-invariant hypersurfaces in semi-dispersing billiards
flow-invariant hypersurfaces in semi-dispersing billiards
attempts solve boltzmann sinai ergodicity ball gases. crucial balls hypersurfaces consisting degenerate trajectories hyperbolicity hypersurface dispersing billiard lyapunov grows linearly time. boltzmann sinai argument
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2600404
10.1007/s00023-006-0315-3
To study the location of poles for the acoustic scattering matrix for two strictly convex obstacles with smooth boundaries, one uses an approximation of the quantized billiard operator $M$ along the trapped ray between the two obstacles. Using this method Ikawa and G{\'e}rard established the existence of parallel rows of poles in a strip $Im z\leq c$ as $Re z$ tends to infinity. Assuming that the boundaries are analytic and the eigenvalues of Poincar{\'e} map are non-resonant we use the Birkhoff normal form for $M$ to improve this result and to get the complete asymptotic expansions for the poles in any logarithmic neighborhood of real axis
Scattering Poles Near the Real Axis for Two Strictly Convex Obstacles
scattering poles near the real axis for two strictly convex obstacles
poles acoustic strictly convex obstacles boundaries quantized billiard trapped obstacles. ikawa rard rows poles strip tends infinity. boundaries analytic eigenvalues poincar resonant birkhoff asymptotic expansions poles logarithmic neighborhood
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2557480
10.1007/s00023-006-0316-2
The quasi-static evolution of steady states far from equilibrium is investigated from the point of view of quantum statistical mechanics. As a concrete example of a thermodynamic system, a two-level quantum dot coupled to several reservoirs of free fermions at different temperatures is considered. A novel adiabatic theorem for unbounded and nonnormal generators of evolution is proven and applied to study the quasi-static evolution of nonequilibrium steady states (NESS) of the coupled system.Comment: 39 pages. Some typos corrected. To appear in Ann. Henri Poincar
On the quasi-static evolution of nonequilibrium steady states
on the quasi-static evolution of nonequilibrium steady states
quasi steady mechanics. concrete thermodynamic reservoirs fermions considered. adiabatic unbounded nonnormal generators proven quasi nonequilibrium steady ness pages. typos corrected. ann. henri poincar
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2557587
10.1007/s00023-006-0320-1
We investigate regularity properties of molecular one-electron densities rho near the nuclei. In particular we derive a representation rho(x)=mu(x)*(e^F(x)) with an explicit function F, only depending on the nuclear charges and the positions of the nuclei, such that mu belongs to C^{1,1}(R^3), i.e., mu has locally essentially bounded second derivatives. An example constructed using Hydrogenic eigenfunctions shows that this regularity result is sharp. For atomic eigenfunctions which are either even or odd with respect to inversion in the origin, we prove that mu is even C^{2,\alpha}(R^3) for all alpha in (0,1). Placing one nucleus at the origin we study rho in polar coordinates x=r*omega and investigate rho'(r,omega) and rho''(r,omega) for fixed omega as r tends to zero. We prove non-isotropic cusp conditions of first and second order, which generalize Kato's classical result.Comment: 19 page
Non-isotropic cusp conditions and regularity of the electron density of molecules at the nuclei
non-isotropic cusp conditions and regularity of the electron density of molecules at the nuclei
regularity densities nuclei. derive charges nuclei belongs i.e. locally essentially derivatives. hydrogenic eigenfunctions regularity sharp. eigenfunctions inversion alpha alpha placing nucleus polar omega omega omega omega tends zero. isotropic cusp generalize kato
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2556279
10.1007/s00023-006-0322-z
For Schroedinger operators (including those with magnetic fields) with singular (locally integrable) scalar potentials on manifolds of bounded geometry, we study continuity properties of some related integral kernels: the heat kernel, the Green function, and also kernels of some other functions of the operator. In particular, we show the joint continuity of the heat kernel and the continuity of the Green function outside the diagonal. The proof makes intensive use of the Lippmann-Schwinger equation.Comment: 38 pages, major revision; to appear in Annales Henri Poincare (2007
Continuity properties of integral kernels associated with Schroedinger operators on manifolds
continuity properties of integral kernels associated with schroedinger operators on manifolds
schroedinger singular locally integrable potentials manifolds continuity kernels kernel kernels operator. continuity kernel continuity diagonal. intensive lippmann schwinger pages revision annales henri poincare
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2434543
10.1007/s00023-006-0323-3
We study formal expansions of asymptotically flat solutions to the static vacuum field equations which are determined by minimal sets of freely specifyable data referred to as `null data'. These are given by sequences of symmetric trace free tensors at space-like infinity of increasing order. They are 1:1 related to the sequences of Geroch multipoles. Necessary and sufficient growth estimates on the null data are obtained for the formal expansions to be absolutely convergent. This provides a complete characterization of all asymptotically flat solutions to the static vacuum field equations.Comment: 65 page
Static vacuum solutions from convergent null data expansions at space-like infinity
static vacuum solutions from convergent null data expansions at space-like infinity
formal expansions asymptotically freely specifyable referred trace tensors infinity order. geroch multipoles. formal expansions absolutely convergent. asymptotically
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2594067
10.1007/s00023-006-0325-1
We study the theory of scattering for the Maxwell-Schr"odinger system in space dimension 3, in the Coulomb gauge. We prove the existence of modified wave operators for that system with no size restriction on the Schr"odinger and Maxwell asymptotic data and we determine the asymptotic behaviour in time of solutions in the range of the wave operators. The method consists in partially solving the Maxwell equations for the potentials, substituting the result into the Schr"odinger equation, which then becomes both nonlinear and nonlocal in time. The Schr"odinger function is then parametrized in terms of an amplitude and a phase satisfying a suitable auxiliary system, and the Cauchy problem for that system, with prescribed asymptotic behaviour determined by the asymptotic data, is solved by an energy method, thereby leading to solutions of the original system with prescribed asymptotic behaviour in time. This paper is the generalization of a previous paper with the same title. However it is entirely selfcontained and can be read without any previous knowledge of the latter.Comment: latex 96 page
Long Range Scattering and Modified Wave Operators for the Maxwell-Schr"odinger System II. The general case
long range scattering and modified wave operators for the maxwell-schr"odinger system ii. the general case
maxwell schr odinger coulomb gauge. restriction schr odinger maxwell asymptotic asymptotic operators. partially solving maxwell potentials substituting schr odinger nonlocal time. schr odinger parametrized satisfying auxiliary cauchy prescribed asymptotic asymptotic solved thereby prescribed asymptotic time. generalization title. entirely selfcontained read latex
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2557468
10.1007/s00023-007-0326-8
In the framework of the theory of an electron in a periodic potential, we reconsider the longstanding problem of the existence of smooth and periodic quasi-Bloch functions, which is shown to be equivalent to the triviality of the Bloch bundle. By exploiting the time-reversal symmetry of the Hamiltonian and some bundle-theoretic methods, we show that the problem has a positive answer for any d < 4, thus generalizing a previous result by G. Nenciu. We provide a general formulation of the result, aiming at the application to the Dirac equation with a periodic potential and to piezoelectricity.Comment: 20 pages, no figure
Triviality of Bloch and Bloch-Dirac bundles
triviality of bloch and bloch-dirac bundles
reconsider longstanding quasi bloch triviality bloch bundle. exploiting reversal bundle theoretic answer generalizing nenciu. formulation aiming dirac pages
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2434686
10.1007/s00023-007-0333-9
Some future global properties of cosmological solutions for the Einstein-Vlasov-Maxwell system with surface symmetry are presented. Global existence is proved, the homogeneous spacetimes are future complete for causal trajectories, and the same is true for inhomogeneous plane-symmetric solutions with small initial data. In the latter case some decay properties are also obtained at late times. Similar but slightly weaker results hold for hyperbolic symmetry.Comment: 34 pages, version to be published in AH
On surface-symmetric spacetimes with collisionless and charged matter
on surface-symmetric spacetimes with collisionless and charged matter
cosmological einstein vlasov maxwell presented. proved homogeneous spacetimes causal trajectories inhomogeneous data. times. weaker hold hyperbolic pages
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2558319
10.1007/s00023-007-0337-5
The bipolaron are two electrons coupled to the elastic deformations of an ionic crystal. We study this system in the Fr\"{o}hlich approximation. If the Coulomb repulsion dominates, the lowest energy states are two well separated polarons. Otherwise the electrons form a bound pair. We prove the validity of the Pekar-Tomasevich energy functional in the strong coupling limit, yielding estimates on the coupling parameters for which the binding energy is strictly positive. Under the condition of a strictly positive binding energy we prove the existence of a ground state at fixed total momentum $P$, provided $P$ is not too large.Comment: 31 page
The bipolaron in the strong coupling limit
the bipolaron in the strong coupling limit
bipolaron elastic deformations ionic crystal. hlich approximation. coulomb repulsion dominates separated polarons. pair. validity pekar tomasevich yielding strictly positive. strictly
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2557955
10.1007/s00023-007-0338-4
We consider the Laplacian in $\mathbb{R}^n$ perturbed by a finite number of distant perturbations those are abstract localized operators. We study the asymptotic behaviour of the discrete spectrum as the distances between perturbations tend to infinity. The main results are the convergence theorem and the asymptotics expansions for the eigenelements. Some examples of the possible distant perturbations are given; they are potential, second order differential operator, magnetic Schrodinger operator, integral operator, and $\d$-potential
Distant perturbations of the Laplacian in a multi-dimensional space
distant perturbations of the laplacian in a multi-dimensional space
laplacian mathbb perturbed distant perturbations localized operators. asymptotic distances perturbations tend infinity. asymptotics expansions eigenelements. distant perturbations schrodinger
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2557935
10.1007/s00023-007-0341-9
We consider a natural generalization of Haag duality to the case in which the observable algebra is restricted to a subset of the space-time and is not irreducible: the commutant and the causal complement have to be considered relatively to the ambient space. We prove this relative form of Haag duality under quite general conditions for the free scalar and electromagnetic field of space dimension d>1 in the vacuum representation. Such property is interesting in view of a theory of superselection sectors for the electromagnetic field.Comment: 22 page
Relative Haag Duality for the Free Field in Fock Representation
relative haag duality for the free field in fock representation
generalization haag duality observable restricted irreducible commutant causal complement ambient space. haag duality electromagnetic representation. superselection sectors electromagnetic
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2557574
10.1007/s00023-007-0346-4
We study a small quantum system (e.g. a simplified model for an atom or molecule) interacting with two bosonic or fermionic reservoirs (say, photon or phonon fields). We show that the combined system has a family of stationary states, parametrized by two numbers $T_1$, $T_2$ (``reservoir temperatures''). If $T_1\neq T_2$, then these states are non-equilibrium, stationary states (NESS). In the latter case we show that they have nonvanishing heat fluxes and positive entropy production. Furthermore, we show that these states are dynamically asymptotically stable. The latter means that the evolution with an initial condition, normal with respect to any state where the reservoirs are in equilibria at temperatures $T_1$ and $T_2$, converges to the corresponding NESS. Our results are valid for the temperatures satisfying the bound $\min(T_1, T_2) > g^{2+\alpha}$, where $g$ is the coupling constant and $0< \alpha<1$ is a power related to the infra-red behaviour of the coupling functions.Comment: 1 figure. To appear in Ann. H. Poincar
Theory of Non-Equilibrium Sationary States as a Theory of Resonances
theory of non-equilibrium sationary states as a theory of resonances
e.g. simplified atom molecule interacting bosonic fermionic reservoirs phonon stationary parametrized reservoir stationary ness nonvanishing fluxes production. dynamically asymptotically stable. reservoirs equilibria converges ness. valid satisfying alpha alpha infra figure. ann. poincar
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2601538
10.1007/s00023-007-0348-2
The Witten spinorial argument has been adapted in several works over the years to prove positivity of mass in the asymptotically AdS and asymptotically hyperbolic settings in arbitrary dimensions. In this paper we prove a scalar curvature rigidity result and a positive mass theorem for asymptotically hyperbolic manifolds that do not require a spin assumption. The positive mass theorem is reduced to the rigidity case by a deformation construction near the conformal boundary. The proof of the rigidity result is based on a study of minimizers of the BPS brane action.Comment: 42 pages, 2 figure
Rigidity and Positivity of Mass for Asymptotically Hyperbolic Manifolds
rigidity and positivity of mass for asymptotically hyperbolic manifolds
witten spinorial argument adapted positivity asymptotically asymptotically hyperbolic settings dimensions. curvature rigidity asymptotically hyperbolic manifolds assumption. rigidity deformation conformal boundary. rigidity minimizers brane pages
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1937598
10.1007/s00023-007-0349-1
It is known that, in an asymptotically flat spacetime, null infinity cannot act as an initial-value surface for massive real scalar fields. Exploiting tools proper of harmonic analysis on hyperboloids and global norm estimates for the wave operator, we show that it is possible to circumvent such obstruction at least in Minkowski spacetime. Hence we project norm-finite solutions of the Klein-Gordon equation of motion in data on null infinity and, eventually, we interpret them in terms of boundary free field theory.Comment: 26 page
Projecting Massive Scalar Fields to Null Infinity
projecting massive scalar fields to null infinity
asymptotically spacetime infinity massive fields. exploiting proper harmonic hyperboloids norm circumvent obstruction minkowski spacetime. norm klein gordon infinity eventually interpret
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2558532
10.1007/s00023-007-0352-6
We study the volume of nodal sets for eigenfunctions of the Laplacian on the standard torus in two or more dimensions. We consider a sequence of eigenvalues $4\pi^2\eigenvalue$ with growing multiplicity $\Ndim\to\infty$, and compute the expectation and variance of the volume of the nodal set with respect to a Gaussian probability measure on the eigenspaces. We show that the expected volume of the nodal set is $const \sqrt{\eigenvalue}$. Our main result is that the variance of the volume normalized by $\sqrt{\eigenvalue}$ is bounded by $O(1/\sqrt{\Ndim})$, so that the normalized volume has vanishing fluctuations as we increase the dimension of the eigenspace.Comment: 20 pages, Was accepted for publication in the Annales Henri Poincar
On the volume of nodal sets for eigenfunctions of the Laplacian on the torus
on the volume of nodal sets for eigenfunctions of the laplacian on the torus
nodal eigenfunctions laplacian torus dimensions. eigenvalues eigenvalue growing multiplicity ndim infty expectation nodal eigenspaces. nodal const sqrt eigenvalue sqrt eigenvalue sqrt ndim vanishing pages publication annales henri poincar
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2600222
10.1007/s00023-007-0353-5
We consider an open manifold which is the interior of a compact manifold with boundary. Assuming gauge invariance, we classify magnetic fields with compact support into being trapping or non-trapping. We study spectral properties of the associated magnetic Laplacian for a class of Riemannian metrics which includes complete hyperbolic metrics of finite volume. When $B$ is non-trapping, the magnetic Laplacian has nonempty essential spectrum. Using Mourre theory, we show the absence of singular continuous spectrum and the local finiteness of the point spectrum. When $B$ is trapping, the spectrum is discrete and obeys the Weyl law. The existence of trapping magnetic fields with compact support depends on cohomological conditions, indicating a new and very strong long-range effect. In the non-gauge invariant case, we exhibit a strong Aharonov-Bohm effect. On hyperbolic surfaces with at least two cusps, we show that the magnetic Laplacian associated to every magnetic field with compact support has purely discrete spectrum for some choices of the vector potential, while other choices lead to a situation of limit absorption principle. We also study perturbations of the metric. We show that in the Mourre theory it is not necessary to require a decay of the derivatives of the perturbation. This very singular perturbation is then brought closer to the perturbation of a potential.Comment: 52 pages. Revised version: references added. To appear in Annales Henri Poincar\'
Spectral analysis of magnetic Laplacians on conformally cusp manifolds
spectral analysis of magnetic laplacians on conformally cusp manifolds
manifold interior manifold boundary. invariance classify trapping trapping. laplacian riemannian metrics hyperbolic metrics volume. trapping laplacian nonempty spectrum. mourre singular finiteness spectrum. trapping obeys weyl law. trapping cohomological effect. exhibit aharonov bohm effect. hyperbolic cusps laplacian purely choices choices principle. perturbations metric. mourre derivatives perturbation. singular perturbation brought closer perturbation pages. revised added. annales henri poincar
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1940185
10.1007/s00023-007-0354-4
We consider a class of translationally invariant magnetic fields such that the corresponding potential has a constant direction. Our goal is to study basic spectral properties of the Schr\"odinger operator ${\bf H}$ with such a potential. In particular, we show that the spectrum of ${\bf H}$ is absolutely continuous and we find its location. Then we study the long-time behaviour of solutions $\exp(-i {\bf H} t)f$ of the time dependent Schr\"odinger equation. It turnes out that a quantum particle remains localized in the plane orthogonal to the direction of the potential. Its propagation in this direction is determined by group velocities. It is to a some extent similar to a evolution of a one-dimensional free particle but "exits" to $+\infty$ and $-\infty$ might be essentially different
On spectral properties of translationally invariant magnetic Schr\"odinger operators
on spectral properties of translationally invariant magnetic schr\"odinger operators
translationally direction. goal schr odinger potential. absolutely location. schr odinger equation. turnes localized orthogonal potential. propagation velocities. exits infty infty essentially
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1960759
10.1007/s00023-008-0359-7
An algebra previously proposed as an asymptotic field structure in electrodynamics is considered in respect of localization properties of fields. Fields are 'spatially local' -- localized in regions resulting as unions of two intersecting (solid) lightcones: a future- and a past-lightcone. This localization remains in concord with the usual idealizations connected with the scattering theory. Fields thus localized naturally include infrared characteristics normally placed at spacelike infinity and form a structure respecting Gauss law. When applied to the description of the radiation of an external classical current the model is free of 'infrared catastrophe'.Comment: 30 pages; accepted for publication in Ann. Henri Poincare; a few minor correction
Infrared problem and spatially local observables in electrodynamics
infrared problem and spatially local observables in electrodynamics
asymptotic electrodynamics localization fields. spatially localized unions intersecting lightcones lightcone. localization concord usual idealizations theory. localized naturally infrared normally placed spacelike infinity respecting gauss law. infrared catastrophe .comment pages publication ann. henri poincare minor
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1947697
10.1007/s00023-008-0365-9
We consider a system of N nonrelativistic particles of spin 1/2 interacting with the quantized Maxwell field (mass zero and spin one) in the limit when the particles have a small velocity, imposing to the interaction an ultraviolet cutoff, but no infrared cutoff. Two ways to implement the limit are considered: c going to infinity with the velocity v of the particles fixed, the case for which rigorous results have already been discussed in the literature, and v going to 0 with c fixed. The second case can be rephrased as the limit of heavy particles, m_{j} --> epsilon^{-2}m_{j}, observed over a long time, t --> epsilon^{-1}t, epsilon --> 0^{+}, with kinetic energy E_{kin} = Or(1). Focusing on the second approach we construct subspaces which are invariant for the dynamics up to terms of order epsilon sqrt{log(epsilon^{-1})} and describe effective dynamics, for the particles only, inside them. At the lowest order the particles interact through Coulomb potentials. At the second one, epsilon^{2}, the mass gets a correction of electromagnetic origin and a velocity dependent interaction, the Darwin term, appears. Moreover, we calculate the radiated piece of the wave function, i. e., the piece which leaks out of the almost invariant subspaces and calculate the corresponding radiated energy.Comment: 46 pages, no figures. Minor changes in the introduction and correction of some typos. Version accepted for publication in Annales Henri Poincare
Quasi-static Limits in Nonrelativistic Quantum Electrodynamics
quasi-static limits in nonrelativistic quantum electrodynamics
nonrelativistic interacting quantized maxwell imposing ultraviolet cutoff infrared cutoff. ways implement going infinity rigorous going fixed. rephrased epsilon epsilon epsilon focusing subspaces epsilon sqrt epsilon them. interact coulomb potentials. epsilon gets electromagnetic darwin appears. radiated piece piece leaks subspaces radiated pages figures. minor typos. publication annales henri poincare
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1963624
10.1007/s00023-008-0368-6
We construct large families of initial data sets for the vacuum Einstein equations with positive cosmological constant which contain exactly Delaunay ends; these are non-trivial initial data sets which coincide with those for the Kottler-Schwarzschild-de Sitter metrics in regions of infinite extent. From the purely Riemannian geometric point of view, this produces complete, constant positive scalar curvature metrics with exact Delaunay ends which are not globally Delaunay. The ends can be used to construct new compact initial data sets via gluing constructions. The construction provided applies to more general situations where the asymptotic geometry may have non-spherical cross-sections consisting of Einstein metrics with positive scalar curvature.Comment: Minor changes, updated references. Final version. To appear in Annales Henri Poincar
Singular Yamabe metrics and initial data with exactly Kottler-Schwarzschild-de Sitter ends
singular yamabe metrics and initial data with exactly kottler-schwarzschild-de sitter ends
families einstein cosmological delaunay ends trivial coincide kottler schwarzschild sitter metrics infinite extent. purely riemannian geometric produces curvature metrics delaunay ends globally delaunay. ends gluing constructions. applies situations asymptotic spherical consisting einstein metrics minor updated references. version. annales henri poincar
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2600391
10.1007/s00023-008-0372-x
Consider the Schroedinger operator with semiclassical parameter h, in the limit where h goes to zero. When the involved long-range potential is smooth, it is well known that the boundary values of the operator's resolvent at a positive energy E are bounded by O(1/h) if and only if the associated Hamilton flow is non-trapping at energy E. In the present paper, we extend this result to the case where the potential may possess Coulomb singularities. Since the Hamilton flow then is not complete in general, our analysis requires the use of an appropriate regularization.Comment: 39 pages, no figures, corrected versio
Semiclassical resolvent estimates for Schroedinger operators with Coulomb singularities
semiclassical resolvent estimates for schroedinger operators with coulomb singularities
schroedinger semiclassical goes zero. resolvent hamilton trapping extend possess coulomb singularities. hamilton pages corrected versio
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1940923
10.1007/s00023-008-0381-9
We study the general structure of Fermi conformal nets of von Neumann algebras on the circle, consider a class of topological representations, the general representations, that we characterize as Neveu-Schwarz or Ramond representations, in particular a Jones index can be associated with each of them. We then consider a supersymmetric general representation associated with a Fermi modular net and give a formula involving the Fredholm index of the supercharge operator and the Jones index. We then consider the net associated with the super-Virasoro algebra and discuss its structure. If the central charge c belongs to the discrete series, this net is modular by the work of F. Xu and we get an example where our setting is verified by considering the Ramond irreducible representation with lowest weight c/24. We classify all the irreducible Fermi extensions of any super-Virasoro net in the discrete series, thus providing a classification of all superconformal nets with central charge less than 3/2.Comment: 49 pages. Section 8 has been removed. More details concerning the diffeomorphism covariance are give
Structure and Classification of Superconformal Nets
structure and classification of superconformal nets
fermi conformal nets neumann algebras circle topological representations representations characterize neveu schwarz ramond representations jones them. supersymmetric fermi modular involving fredholm supercharge jones index. super virasoro structure. belongs modular verified ramond irreducible classify irreducible fermi extensions super virasoro superconformal nets pages. removed. concerning diffeomorphism covariance
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2558544
10.1007/s00023-008-0382-8
Devices exhibiting the integer quantum Hall effect can be modeled by one-electron Schroedinger operators describing the planar motion of an electron in a perpendicular, constant magnetic field, and under the influence of an electrostatic potential. The electron motion is confined to bounded or unbounded subsets of the plane by confining potential barriers. The edges of the confining potential barriers create edge currents. This is the second of two papers in which we review recent progress and prove explicit lower bounds on the edge currents associated with one- and two-edge geometries. In this paper, we study various unbounded and bounded, two-edge geometries with soft and hard confining potentials. These two-edge geometries describe the electron confined to unbounded regions in the plane, such as a strip, or to bounded regions, such as a finite length cylinder. We prove that the edge currents are stable under various perturbations, provided they are suitably small relative to the magnetic field strength, including perturbations by random potentials. The existence of, and the estimates on, the edge currents are independent of the spectral type of the operator.Comment: 57 page
Edge Currents for Quantum Hall Systems, II. Two-Edge, Bounded and Unbounded Geometries
edge currents for quantum hall systems, ii. two-edge, bounded and unbounded geometries
devices exhibiting integer hall modeled schroedinger describing planar perpendicular electrostatic potential. confined unbounded subsets confining barriers. confining barriers create currents. papers progress bounds currents geometries. unbounded geometries confining potentials. geometries confined unbounded strip cylinder. currents perturbations suitably perturbations potentials. currents
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84091729
10.1007/s00023-008-0383-7
We analyze a general class of self-adjoint difference operators $H_\varepsilon = T_\varepsilon + V_\varepsilon$ on $\ell^2(\varepsilon\mathbb{Z}^d)$, where $V_\varepsilon$ is a one-well potential and $\varepsilon$ is a small parameter. We construct a Finslerian distance $d$ induced by $H_\varepsilon$ and show that short integral curves are geodesics. Then we show that Dirichlet eigenfunctions decay exponentially with a rate controlled by the Finsler distance to the well. This is analog to semiclassical Agmon estimates for Schr\"odinger operators.Comment: 27 page
Agmon-Type Estimates for a Class of Difference Operators
agmon-type estimates for a class of difference operators
analyze adjoint varepsilon varepsilon varepsilon varepsilon mathbb varepsilon varepsilon parameter. finslerian varepsilon geodesics. dirichlet eigenfunctions exponentially finsler well. analog semiclassical agmon schr odinger
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2435750
10.1007/s00023-008-0385-5
We give conditions on a general stress-energy tensor T_{\alpha \beta} in a spherically symmetric black hole spacetime which are sufficient to guarantee that the black hole will contain a (spherically symmetric) marginally trapped tube which is eventually achronal, connected, and asymptotic to the event horizon. Price law decay per se is not required for this asymptotic result, and in this general setting, such decay only implies that the marginally trapped tube has finite length with respect to the induced metric. We do, however, impose a smallness condition (B1) which one may obtain in practice by imposing decay on the T_{vv} component of the stress-energy tensor. We give two applications of the theorem to self-gravitating Higgs field spacetimes, one using weak Price law decay, the other certain strong smallness and monotonicity assumptions.Comment: 43 pages, 7 figures. Updated to agree with published version; Theorem 1 strengthened slightly, minor issues fixe
Asymptotic Behavior of Spherically Symmetric Marginally Trapped Tubes
asymptotic behavior of spherically symmetric marginally trapped tubes
alpha beta spherically spacetime guarantee spherically marginally trapped tube eventually achronal asymptotic horizon. asymptotic marginally trapped tube metric. impose smallness imposing tensor. gravitating spacetimes smallness monotonicity pages figures. updated agree strengthened minor fixe
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2029971
10.1007/s00023-009-0007-x
In this paper we tackle the problem of constructing explicit examples of topological cocycles of Roberts' net cohomology, as defined abstractly by Brunetti and Ruzzi. We consider the simple case of massive bosonic quantum field theory on the two dimensional Einstein cylinder. After deriving some crucial results of the algebraic framework of quantization, we address the problem of the construction of the topological cocycles. All constructed cocycles lead to unitarily equivalent representations of the fundamental group of the circle (seen as a diffeomorphic image of all possible Cauchy surfaces). The construction is carried out using only Cauchy data and related net of local algebras on the circle.Comment: 41 pages, title changed, minor changes, typos corrected, references added. Accepted for publication in Ann. Henri Poincare
Topological features of massive bosons on two dimensional Einstein space-time
topological features of massive bosons on two dimensional einstein space-time
tackle constructing topological cocycles roberts cohomology abstractly brunetti ruzzi. massive bosonic einstein cylinder. deriving crucial algebraic quantization topological cocycles. cocycles unitarily representations circle diffeomorphic cauchy cauchy algebras pages title changed minor typos corrected added. publication ann. henri poincare
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2094525
10.1007/s00023-009-0019-6
There are five known classes of lattice equations that hold in every infinite dimensional Hilbert space underlying quantum systems: generalised orthoarguesian, Mayet's E_A, Godowski, Mayet-Godowski, and Mayet's E equations. We obtain a result which opens a possibility that the first two classes coincide. We devise new algorithms to generate Mayet-Godowski equations that allow us to prove that the fourth class properly includes the third. An open problem related to the last class is answered. Finally, we show some new results on the Godowski lattices characterising the third class of equations.Comment: 24 pages, 3 figure
Hilbert Lattice Equations
hilbert lattice equations
hold infinite hilbert generalised orthoarguesian mayet godowski mayet godowski mayet equations. opens coincide. devise mayet godowski fourth properly third. answered. godowski lattices characterising pages
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1955094
10.1007/s00023-009-0400-5
Consider (for simplicity) two one-dimensional semi-infinite leads coupled to a quantum well via time dependent point interactions. In the remote past the system is decoupled, and each of its components is at thermal equilibrium. In the remote future the system is fully coupled. We define and compute the non equilibrium steady state (NESS) generated by this evolution. We show that when restricted to the subspace of absolute continuity of the fully coupled system, the state does not depend at all on the switching. Moreover, we show that the stationary charge current has the same invariant property, and derive the Landau-Lifschitz and Landauer-Buttiker formulas.Comment: 30 pages, submitte
The effect of time-dependent coupling on non-equilibrium steady states
the effect of time-dependent coupling on non-equilibrium steady states
simplicity infinite interactions. remote decoupled equilibrium. remote coupled. steady ness evolution. restricted subspace continuity switching. stationary derive landau lifschitz landauer buttiker pages submitte
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2530634
10.1007/s00023-009-0401-4
We study dispersion relations in the noncommutative \phi^3 and Wess-Zumino model in the Yang-Feldman formalism at one-loop order. Nonplanar graphs lead to a distortion of the dispersion relation. We find that the strength of this effect is moderate if the scale of noncommutativity is identified with the Planck scale and parameters typical for a Higgs field are employed. The contribution of the nonplanar graphs is calculated rigorously using the framework of oscillatory integrals.Comment: 23 pages, 2 figures. v2: Minor corrections and changes in the presentatio
Dispersion relations in the noncommutative \phi^3 and Wess-Zumino model in the Yang-Feldman formalism
dispersion relations in the noncommutative \phi^3 and wess-zumino model in the yang-feldman formalism
noncommutative wess zumino feldman formalism order. nonplanar distortion relation. moderate noncommutativity planck employed. nonplanar rigorously oscillatory pages figures. minor presentatio
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2027646
10.1007/s00023-009-0412-1
Let $\Omega$ be a bounded domain in $R^n$ with $C^2$-smooth boundary of co-dimension 1, and let $H=-\Delta +V(x)$ be a Schr\"odinger operator on $\Omega$ with potential V locally bounded. We seek the weakest conditions we can find on the rate of growth of the potential V close to the boundary which guarantee essential self-adjointness of H on $C_0^\infty(\Omega)$. As a special case of an abstract condition, we add optimal logarithmic type corrections to the known condition $V(x)\geq \frac{3}{4d(x)^2}$, where $d(x)=dist(x,\partial\Omega)$. The constant 1 in front of each logarithmic term in Theorem 2 is optimal. The proof is based on a refined Agmon exponential estimate combined with a well known multidimensional Hardy inequality
On confining potentials and essential self-adjointness for Schr\"odinger operators on bounded domains in R^n
on confining potentials and essential self-adjointness for schr\"odinger operators on bounded domains in r^n
omega delta schr odinger omega locally bounded. seek weakest guarantee adjointness infty omega logarithmic frac dist omega front logarithmic optimal. refined agmon exponential multidimensional hardy inequality
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2027798
10.1007/s00023-009-0421-0
We study a toy model for "partially open" wave-mechanical system, like for instance a dielectric micro-cavity, in the semiclassical limit where ray dynamics is applicable. Our model is a quantized map on the 2-dimensional torus, with an additional damping at each time step, resulting in a subunitary propagator, or "damped quantum map". We obtain analogues of Weyl's laws for such maps in the semiclassical limit, and draw some more precise estimates when the classical dynamic is chaotic.Comment: 35 pages, 5 figures. Corrected typos. Some proofs clarifie
Weyl laws for partially open quantum maps
weyl laws for partially open quantum maps
partially dielectric micro cavity semiclassical applicable. quantized torus damping subunitary propagator damped analogues weyl laws semiclassical draw precise pages figures. corrected typos. proofs clarifie
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2073996
10.1007/s00023-010-0021-z
We analyze the time evolution describing a quantum source for noninteracting particles, either bosons or fermions. The growth behaviour of the particle number (trace of the density matrix) is investigated, leading to spectral criteria for sublinear or linear growth in the fermionic case, but also establishing the possibility of exponential growth for bosons. We further study the local convergence of the density matrix in the long time limit and prove the semiclassical limit.Comment: 24 pages; In the new version, we added several references concerning open quantum systems and present an extended result on linear particle production in the fermionic cas
Dynamical phase transition for a quantum particle source
dynamical phase transition for a quantum particle source
analyze describing noninteracting bosons fermions. trace sublinear fermionic establishing exponential bosons. semiclassical pages concerning fermionic
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2072865
10.1007/s00023-010-0025-8
We develop a gluing construction which adds scaled and truncated asymptotically Euclidean solutions of the Einstein constraint equations to compact solutions with potentially non-trivial cosmological constants. The result is a one-parameter family of initial data which has ordinary and scaled "point-particle" limits analogous to those of Gralla and Wald ("A rigorous derivation of gravitational self-force," Class. Quantum Grav. 2008). In particular, we produce examples of initial data which generalize Schwarzschild - de Sitter initial data and gluing theorems of IMP-type
A Gluing Construction Regarding Point Particles in General Relativity
a gluing construction regarding point particles in general relativity
gluing adds scaled truncated asymptotically euclidean einstein potentially trivial cosmological constants. ordinary scaled analogous gralla wald rigorous derivation gravitational class. grav. generalize schwarzschild sitter gluing theorems
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2017048
10.1007/s00023-010-0027-6
Let (g,K)(k) be a CMC (vacuum) Einstein flow over a compact three-manifold M with non-positive Yamabe invariant (Y(M)). As noted by Fischer and Moncrief, the reduced volume V(k)=(-k/3)^{3}Vol_{g(k)}(M) is monotonically decreasing in the expanding direction and bounded below by V_{\inf}=(-1/6)Y(M))^{3/2}. Inspired by this fact we define the ground state of the manifold M as "the limit" of any sequence of CMC states {(g_{i},K_{i})} satisfying: i. k_{i}=-3, ii. V_{i} --> V_{inf}, iii. Q_{0}((g_{i},K_{i}))< L where Q_{0} is the Bel-Robinson energy and L is any arbitrary positive constant. We prove that (as a geometric state) the ground state is equivalent to the Thurston geometrization of M. Ground states classify naturally into three types. We provide examples for each class, including a new ground state (the Double Cusp) that we analyze in detail. Finally consider a long time and cosmologically normalized flow (\g,\K)(s)=((-k/3)^{2}g,(-k/3))K) where s=-ln(-k) is in [a,\infty). We prove that if E_{1}=E_{1}((\g,\K))< L (where E_{1}=Q_{0}+Q_{1}, is the sum of the zero and first order Bel-Robinson energies) the flow (\g,\K)(s) persistently geometrizes the three-manifold M and the geometrization is the ground state if V --> V_{inf}.Comment: 40 pages. This article is an improved version of the second part of the First Version of arXiv:0705.307
The ground state and the long-time evolution in the CMC Einstein flow
the ground state and the long-time evolution in the cmc einstein flow
einstein manifold yamabe fischer moncrief monotonically decreasing expanding inspired manifold satisfying iii. robinson constant. geometric thurston geometrization classify naturally types. cusp analyze detail. cosmologically infty robinson persistently geometrizes manifold geometrization .comment pages.
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2093491
10.1007/s00023-010-0031-x
The states in the irreducible modules of the minimal models can be represented by infinite lattice paths arising from consideration of the corresponding RSOS statistical models. For the M(p,2p+1) models, a completely different path representation has been found recently, this one on a half-integer lattice; it has no known underlying statistical-model interpretation. The correctness of this alternative representation has not yet been demonstrated, even at the level of the generating functions, since the resulting fermionic characters differ from the known ones. This gap is filled here, with the presentation of two versions of a bijection between the two path representations of the M(p,2p+1) states. In addition, a half-lattice path representation for the M(p+1,2p+1) models is stated, and other generalisations suggested.Comment: 20 page
A bijection between paths for the M(p,2p+1) minimal model Virasoro characters
a bijection between paths for the m(p,2p+1) minimal model virasoro characters
irreducible modules infinite paths arising consideration rsos models. integer interpretation. correctness generating fermionic characters ones. filled presentation versions bijection representations states. stated generalisations
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2087414
10.1007/s00023-010-0034-7
Let T be an aperiodic and repetitive tiling of R^d with finite local complexity. Let O be its tiling space with canonical transversal X. The tiling equivalence relation R_X is the set of pairs of tilings in X which are translates of each others, with a certain (etale) topology. In this paper R_X is reconstructed as a generalized "tail equivalence" on a Bratteli diagram, with its standard AF-relation as a subequivalence relation. Using a generalization of the Anderson-Putnam complex, O is identified with the inverse limit of a sequence of finite CW-complexes. A Bratteli diagram B is built from this sequence, and its set of infinite paths dB is homeomorphic to X. The diagram B is endowed with a horizontal structure: additional edges that encode the adjacencies of patches in T. This allows to define an etale equivalence relation R_B on dB which is homeomorphic to R_X, and contains the AF-relation of "tail equivalence".Comment: 34 pages, 4 figure
Tiling groupoids and Bratteli diagrams
tiling groupoids and bratteli diagrams
aperiodic repetitive tiling complexity. tiling canonical transversal tiling equivalence tilings translates etale topology. reconstructed tail equivalence bratteli subequivalence relation. generalization anderson putnam complexes. bratteli built infinite paths homeomorphic endowed encode adjacencies patches etale equivalence homeomorphic tail equivalence .comment pages
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2070981
10.1007/s00023-010-0037-4
We consider a simple model of a cloud chamber consisting of a test particle (the alpha-particle) interacting with two other particles (the atoms of the vapour) subject to attractive potentials centered in $a_1, a_2 \in \mathbb{R}^3$. At time zero the alpha-particle is described by an outgoing spherical wave centered in the origin and the atoms are in their ground state. We show that, under suitable assumptions on the physical parameters of the system and up to second order in perturbation theory, the probability that both atoms are ionized is negligible unless $a_2$ lies on the line joining the origin with $a_1$. The work is a fully time-dependent version of the original analysis proposed by Mott in 1929.Comment: 23 page
A time-dependent perturbative analysis for a quantum particle in a cloud chamber
a time-dependent perturbative analysis for a quantum particle in a cloud chamber
chamber consisting alpha interacting vapour attractive potentials centered mathbb alpha outgoing spherical centered state. assumptions perturbation ionized negligible unless lies joining mott
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2128840
10.1007/s00023-010-0039-2
The spherically symmetric Einstein-Vlasov system is considered in Schwarzschild coordinates and in maximal-isotropic coordinates. An open problem is the issue of global existence for initial data without size restrictions. The main purpose of the present work is to propose a method of approach for general initial data, which improves the regularity of the terms that need to be estimated compared to previous methods. We prove that global existence holds outside the centre in both these coordinate systems. In the Schwarzschild case we improve the bound on the momentum support obtained in \cite{RRS} for compact initial data. The improvement implies that we can admit non-compact data with both ingoing and outgoing matter. This extends one of the results in \cite{AR1}. In particular our method avoids the difficult task of treating the pointwise matter terms. Furthermore, we show that singularities never form in Schwarzschild time for ingoing matter as long as $3m\leq r.$ This removes an additional assumption made in \cite{A1}. Our result in maximal-isotropic coordinates is analogous to the result in \cite{R1}, but our method is different and it improves the regularity of the terms that need to be estimated for proving global existence in general.Comment: 25 pages. To appear in Ann. Henri Poincar\'
Regularity results for the spherically symmetric Einstein-Vlasov system
regularity results for the spherically symmetric einstein-vlasov system
spherically einstein vlasov schwarzschild maximal isotropic coordinates. restrictions. propose improves regularity methods. coordinate systems. schwarzschild cite data. admit ingoing outgoing matter. extends cite avoids treating pointwise terms. singularities never schwarzschild ingoing removes cite maximal isotropic analogous cite improves regularity proving pages. ann. henri poincar
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2095966
10.1007/s00023-010-0041-8
The purpose of this paper is to establish meromorphy properties of the partial scattering amplitude T(lambda,k) associated with physically relevant classes N_{w,alpha}^gamma of nonlocal potentials in corresponding domains D_{gamma,alpha}^delta of the space C^2 of the complex angular momentum lambda and of the complex momentum k (namely, the square root of the energy). The general expression of T as a quotient Theta(lambda,k)/sigma(lambda,k) of two holomorphic functions in D_{gamma,alpha}^delta is obtained by using the Fredholm-Smithies theory for complex k, at first for lambda=l integer, and in a second step for lambda complex (Real(lambda)>-1/2). Finally, we justify the "Watson resummation" of the partial wave amplitudes in an angular sector of the lambda-plane in terms of the various components of the polar manifold of T with equation sigma(lambda,k)=0. While integrating the basic Regge notion of interpolation of resonances in the upper half-plane of lambda, this unified representation of the singularities of T also provides an attractive possible description of antiresonances in the lower half-plane of lambda. Such a possibility, which is forbidden in the usual theory of local potentials, represents an enriching alternative to the standard Breit-Wigner hard-sphere picture of antiresonances.Comment: 85 pages, 2 figure
Nonlocal potentials and complex angular momentum theory
nonlocal potentials and complex angular momentum theory
establish meromorphy lambda physically alpha gamma nonlocal potentials gamma alpha delta lambda quotient theta lambda sigma lambda holomorphic gamma alpha delta fredholm smithies lambda integer lambda lambda justify watson resummation amplitudes lambda polar manifold sigma lambda integrating regge notion interpolation resonances lambda unified singularities attractive antiresonances lambda. forbidden usual potentials enriching breit wigner sphere picture pages
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2065452
10.1007/s00023-010-0043-6
We prove that sufficiently regular solutions to the wave equation $\Box_g\phi=0$ on the exterior of the Schwarzschild black hole obey the estimates $|\phi|\leq C_\delta v_+^{-{3/2}+\delta}$ and $|\partial_t\phi|\leq C_{\delta} v_+^{-2+\delta}$ on a compact region of $r$ and along the event horizon. This is proved with the help of a new vector field commutator that is analogous to the scaling vector field on Minkowski spacetime. This result improves the known decay rates in the region of finite $r$ and along the event horizon.Comment: Remarks and References Adde
Improved decay for solutions to the linear wave equation on a Schwarzschild black hole
improved decay for solutions to the linear wave equation on a schwarzschild black hole
sufficiently exterior schwarzschild obey delta delta delta delta horizon. proved commutator analogous minkowski spacetime. improves remarks adde
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2110799
10.1007/s00023-010-0050-7
Moving beyond the classical additive and multiplicative approaches, we present an "exponential" method for perturbative renormalization. Using Dyson's identity for Green's functions as well as the link between the Faa di Bruno Hopf algebra and the Hopf algebras of Feynman graphs, its relation to the composition of formal power series is analyzed. Eventually, we argue that the new method has several attractive features and encompasses the BPHZ method. The latter can be seen as a special case of the new procedure for renormalization scheme maps with the Rota-Baxter property. To our best knowledge, although very natural from group-theoretical and physical points of view, several ideas introduced in the present paper seem to be new (besides the exponential method, let us mention the notions of counterfactors and of order n bare coupling constants).Comment: revised version; accepted for publication in Annales Henri Poincar
Exponential renormalization
exponential renormalization
moving additive multiplicative exponential perturbative renormalization. dyson bruno hopf hopf algebras feynman formal analyzed. eventually argue attractive encompasses bphz method. renormalization rota baxter property. ideas seem besides exponential mention notions counterfactors bare .comment revised publication annales henri poincar
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39260788
10.1007/s00023-010-0051-6
The asymptotic behavior of the integrated density of states for a randomly perturbed lattice at the infimum of the spectrum is investigated. The leading term is determined when the decay of the single site potential is slow. The leading term depends only on the classical effect from the scalar potential. To the contrary, the quantum effect appears when the decay of the single site potential is fast. The corresponding leading term is estimated and the leading order is determined. In the multidimensional cases, the leading order varies in different ways from the known results in the Poisson case. The same problem is considered for the negative potential. These estimates are applied to investigate the long time asymptotics of Wiener integrals associated with the random potentials
Classical and Quantum Behavior of the Integrated Density of States for a Randomly Perturbed Lattice
classical and quantum behavior of the integrated density of states for a randomly perturbed lattice
asymptotic randomly perturbed infimum investigated. slow. potential. contrary fast. determined. multidimensional varies ways poisson case. potential. asymptotics wiener integrals potentials
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2131587
10.1007/s00023-010-0052-5
We study discrete alloy-type random Schr\"odinger operators on $\ell^2(\mathbb{Z}^d)$. Wegner estimates are bounds on the average number of eigenvalues in an energy interval of finite box restrictions of these types of operators. If the single site potential is compactly supported and the distribution of the coupling constant is of bounded variation a Wegner estimate holds. The bound is polynomial in the volume of the box and thus applicable as an ingredient for a localisation proof via multiscale analysis.Comment: Accepted for publication in AHP. For an earlier version see http://www.ma.utexas.edu/mp_arc-bin/mpa?yn=09-10
Wegner estimate for discrete alloy-type models
wegner estimate for discrete alloy-type models
alloy schr odinger mathbb wegner bounds eigenvalues restrictions operators. compactly wegner holds. applicable ingredient localisation multiscale publication ahp.
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2134694
10.1007/s00023-010-0053-4
This paper continues the investigation of the Casimir effect with the use of the algebraic formulation of quantum field theory in the initial value setting. Basing on earlier papers by one of us (AH) we approximate the Dirichlet and Neumann boundary conditions by simple interaction models whose nonlocality in physical space is under strict control, but which at the same time are admissible from the point of view of algebraic restrictions imposed on models in the context of Casimir backreaction. The geometrical setting is that of the original parallel plates. By scaling our models and taking appropriate limit we approach the sharp boundary conditions in the limit. The global force is analyzed in that limit. One finds in Neumann case that although the sharp boundary interaction is recovered in the norm resolvent sense for each model considered, the total force per area depends substantially on its choice and diverges in the sharp boundary conditions limit. On the other hand the local energy density outside the interaction region, which in the limit includes any compact set outside the strict position of the plates, has a universal limit corresponding to sharp conditions. This is what one should expect in general, and the lack of this discrepancy in Dirichlet case is rather accidental. Our discussion pins down its precise origin: the difference in the order in which scaling limit and integration over the whole space is carried out.Comment: 32 pages, accepted for publication in Ann. H. Poincar
Global vs local Casimir effect
global vs local casimir effect
continues casimir algebraic formulation setting. basing papers approximate dirichlet neumann nonlocality strict admissible algebraic restrictions imposed casimir backreaction. geometrical plates. sharp limit. limit. finds neumann sharp recovered norm resolvent substantially diverges sharp limit. strict plates universal sharp conditions. discrepancy dirichlet accidental. pins precise pages publication ann. poincar
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2102226
10.1007/s00023-010-0056-1
The Chalker Coddington quantum network percolation model is numerically pertinent to the understanding of the delocalization transition of the quantum Hall effect. We study the model restricted to a cylinder of perimeter 2M. We prove firstly that the Lyapunov exponents are simple and in particular that the localization length is finite; secondly that this implies spectral localization. Thirdly we prove a Thouless formula and compute the mean Lyapunov exponent which is independent of M.Comment: 29 pages, 1 figure. New section added in which simplicity of the Lyapunov spectrum and finiteness of the localization length are proven. To appear in Annales Henri Poincar
Localization Properties of the Chalker-Coddington Model
localization properties of the chalker-coddington model
chalker coddington percolation numerically pertinent delocalization hall effect. restricted cylinder perimeter firstly lyapunov exponents localization secondly localization. thirdly thouless lyapunov exponent pages figure. simplicity lyapunov finiteness localization proven. annales henri poincar
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2111981
10.1007/s00023-010-0058-z
We compute the vacuum expectation values of torus knot operators in Chern-Simons theory, and we obtain explicit formulae for all classical gauge groups and for arbitrary representations. We reproduce a known formula for the HOMFLY invariants of torus links and we obtain an analogous formula for Kauffman invariants. We also derive a formula for cable knots. We use our results to test a recently proposed conjecture that relates HOMFLY and Kauffman invariants.Comment: 20 pages, 5 figures; v2: minor changes, version submitted to AHP. The final publication is available at http://www.springerlink.com/content/a2614232873l76h6
Chern-Simons Invariants of Torus Links
chern-simons invariants of torus links
expectation torus knot chern simons formulae representations. reproduce homfly invariants torus links analogous kauffman invariants. derive cable knots. conjecture relates homfly kauffman pages minor submitted ahp. publication
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2116642
10.1007/s00023-010-0062-3
The process of ionization of a hydrogen atom by a short infrared laser pulse is studied in the regime of very large pulse intensity, in the dipole approximation. Let $A$ denote the integral of the electric field of the pulse over time at the location of the atomic nucleus. It is shown that, in the limit where $|A| \to \infty$, the ionization probability approaches unity and the electron is ejected into a cone opening in the direction of $-A$ and of arbitrarily small opening angle. Asymptotics of various physical quantities in $|A|^{-1}$ is studied carefully. Our results are in qualitative agreement with experimental data reported in \cite{1,2}.Comment: 27 pages, 1 figure
Ionization of Atoms by Intense Laser Pulses
ionization of atoms by intense laser pulses
ionization atom infrared dipole approximation. nucleus. infty ionization unity ejected cone opening arbitrarily opening angle. asymptotics quantities carefully. qualitative cite .comment pages
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2121598
10.1007/s00023-010-0063-2
This article contains a detailed and rigorous proof of the construction of a geometric invariant for initial data sets for the Einstein vacuum field equations. This geometric invariant vanishes if and only if the initial data set corresponds to data for the Kerr spacetime, and thus, it characterises this type of data. The construction presented is valid for boosted and non-boosted initial data sets which are, in a sense, asymptotically Schwarzschildean. As a preliminary step to the construction of the geometric invariant, an analysis of a characterisation of the Kerr spacetime in terms of Killing spinors is carried out. A space spinor split of the (spacetime) Killing spinor equation is performed, to obtain a set of three conditions ensuring the existence of a Killing spinor of the development of the initial data set. In order to construct the geometric invariant, we introduce the notion of approximate Killing spinors. These spinors are symmetric valence 2 spinors intrinsic to the initial hypersurface and satisfy a certain second order elliptic equation ---the approximate Killing spinor equation. This equation arises as the Euler-Lagrange equation of a non-negative integral functional. This functional constitutes part of our geometric invariant ---however, the whole functional does not come from a variational principle. The asymptotic behaviour of solutions to the approximate Killing spinor equation is studied and an existence theorem is presented.Comment: 36 pages. Updated references. Technical details correcte
On the construction of a geometric invariant measuring the deviation from Kerr data
on the construction of a geometric invariant measuring the deviation from kerr data
rigorous geometric einstein equations. geometric vanishes kerr spacetime characterises data. valid boosted boosted asymptotically schwarzschildean. preliminary geometric characterisation kerr spacetime killing spinors out. spinor split spacetime killing spinor ensuring killing spinor set. geometric notion approximate killing spinors. spinors valence spinors intrinsic hypersurface satisfy elliptic approximate killing spinor equation. arises euler lagrange functional. constitutes geometric come variational principle. asymptotic approximate killing spinor pages. updated references. correcte
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2151779
10.1007/s00023-010-0065-0
We consider a waveguide modeled by the Laplacian in a straight planar strip. The Dirichlet boundary condition is taken on the upper boundary, while on the lower boundary we impose periodically alternating Dirichlet and Neumann condition assuming the period of alternation to be small. We study the case when the homogenization gives the Neumann condition instead of the alternating ones. We establish the uniform resolvent convergence and the estimates for the rate of convergence. It is shown that the rate of the convergence can be improved by employing a special boundary corrector. Other results are the uniform resolvent convergence for the operator on the cell of periodicity obtained by the Floquet-Bloch decomposition, the two-terms asymptotics for the band functions, and the complete asymptotic expansion for the bottom of the spectrum with an exponentially small error term
On a waveguide with frequently alternating boundary conditions: homogenized Neumann condition
on a waveguide with frequently alternating boundary conditions: homogenized neumann condition
waveguide modeled laplacian straight planar strip. dirichlet impose periodically alternating dirichlet neumann alternation small. homogenization neumann alternating ones. establish resolvent convergence. employing corrector. resolvent periodicity floquet bloch decomposition asymptotics asymptotic exponentially
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2099289
10.1007/s00023-010-0066-z
We show that, in a model where a non-relativistic particle is coupled to a quantized relativistic scalar Bose field, the embedded mass shell of the particle dissolves in the continuum when the interaction is turned on, provided the coupling constant is sufficiently small. More precisely, under the assumption that the fiber eigenvectors corresponding to the putative mass shell are differentiable as functions of the total momentum of the system, we show that a mass shell could exist only at a strictly positive distance from the unperturbed embedded mass shell near the boundary of the energy-momentum spectrum.Comment: Revised version: a remark added at the end of Section
Absence of Embedded Mass Shells: Cerenkov Radiation and Quantum Friction
absence of embedded mass shells: cerenkov radiation and quantum friction
relativistic quantized relativistic bose embedded dissolves continuum turned sufficiently small. precisely fiber eigenvectors putative differentiable strictly unperturbed embedded revised remark
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2141754
10.1007/s00023-010-0067-y
Quasi one-dimensional systems are systems of particles in domains which are of infinite extent in one direction and of uniformly bounded size in all other directions, e.g. on a cylinder of infinite length. The main result proven here is that for such particle systems with Coulomb interactions and neutralizing background, the so-called "jellium", at any temperature and at any finite-strip width there is translation symmetry breaking. This extends the previous result on Laughlin states in thin, two-dimensional strips by Jansen, Lieb and Seiler (2009). The structural argument which is used here bypasses the question of whether the translation symmetry breaking is manifest already at the level of the one particle density function. It is akin to that employed by Aizenman and Martin (1980) for a similar statement concerning symmetry breaking at all temperatures in strictly one-dimensional Coulomb systems. The extension is enabled through bounds which establish tightness of finite-volume charge fluctuations.Comment: 26 pages, 6 figure
Symmetry breaking in quasi-1D Coulomb systems
symmetry breaking in quasi-1d coulomb systems
quasi infinite uniformly directions e.g. cylinder infinite length. proven coulomb neutralizing jellium strip translation breaking. extends laughlin strips jansen lieb seiler argument bypasses translation breaking manifest function. akin aizenman martin statement concerning breaking strictly coulomb systems. enabled bounds establish tightness pages
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2116719
10.1007/s00023-010-0069-9
In this paper, we consider massless Dirac fields propagating in the outer region of de Sitter-Reissner-Nordstr\"om black holes. We show that the metric of such black holes is uniquely determined by the partial knowledge of the corresponding scattering matrix $S(\lambda)$ at a fixed energy $\lambda \ne 0$. More precisely, we consider the partial wave scattering matrices $S(\lambda,n)$ (here $\lambda \ne 0$ is the fixed energy and $n \in \N^*$ denotes the angular momentum) defined as the restrictions of the full scattering matrix on a well chosen basis of spin-weighted spherical harmonics. We prove that the mass $M$, the square of the charge $Q^2$ and the cosmological constant $\Lambda$ of a dS-RN black hole (and thus its metric) can be uniquely determined from the knowledge of either the transmission coefficients $T(\lambda, n)$, or the reflexion coefficients $R(\lambda, n)$ (resp. $L(\lambda, n)$), for all $n \in {\mathcal{L}}$ where $\mathcal{L}$ is a subset of $\N^*$ that satisfies the M\"untz condition $\sum_{n \in {\mathcal{L}}} \frac{1}{n} = +\infty$. Our main tool consists in complexifying the angular momentum $n$ and in studying the analytic properties of the "unphysical" scattering matrix $S(\lambda,z)$ in the complex variable $z$. We show in particular that the quantities $\frac{1}{T(\lambda,z)}$, $\frac{R(\lambda,z)}{T(\lambda,z)}$ and $\frac{L(\lambda,z)}{T(\lambda,z)}$ belong to the Nevanlinna class in the region $\{z \in \C, \ Re(z) >0 \}$ for which we have analytic uniqueness theorems at our disposal. Eventually, as a by-product of our method, we obtain reconstrution formulae for the surface gravities of the event and cosmological horizons of the black hole which have an important physical meaning in the Hawking effect.Comment: 40 page
Inverse scattering at fixed energy in de Sitter-Reissner-Nordstr\"om black holes
inverse scattering at fixed energy in de sitter-reissner-nordstr\"om black holes
massless dirac propagating outer sitter reissner nordstr holes. holes uniquely lambda lambda precisely lambda lambda restrictions weighted spherical harmonics. cosmological lambda uniquely lambda reflexion lambda resp. lambda mathcal mathcal satisfies untz mathcal frac infty complexifying studying analytic unphysical lambda quantities frac lambda frac lambda lambda frac lambda lambda belong nevanlinna analytic uniqueness theorems disposal. eventually reconstrution formulae gravities cosmological horizons meaning hawking
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2145062
10.1007/s00023-010-0070-3
We consider asymptotically flat Riemannian manifolds with nonnegative scalar curvature that are conformal to $\R^{n}\setminus \Omega, n\ge 3$, and so that their boundary is a minimal hypersurface. (Here, $\Omega\subset \R^{n}$ is open bounded with smooth mean-convex boundary.) We prove that the ADM mass of any such manifold is bounded below by $(V/\beta_{n})^{(n-2)/n}$, where $V$ is the Euclidean volume of $\Omega$ and $\beta_{n}$ is the volume of the Euclidean unit $n$-ball. This gives a partial proof to a conjecture of Bray and Iga \cite{brayiga}. Surprisingly, we do not require the boundary to be outermost.Comment: 7 page
A volumetric Penrose inequality for conformally flat manifolds
a volumetric penrose inequality for conformally flat manifolds
asymptotically riemannian manifolds nonnegative curvature conformal setminus omega hypersurface. omega convex boundary. manifold beta euclidean omega beta euclidean ball. conjecture bray cite brayiga surprisingly
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2149107
10.1007/s00023-010-0072-1
In this paper we employ a novel technique combining the Euler Maclaurin formula with the saddle point approximation method to obtain the asymptotic behavior (in the limit of large representation index $J$) of generic Wigner matrix elements $D^{J}_{MM'}(g)$. We use this result to derive asymptotic formulae for the character $\chi^J(g)$ of an SU(2) group element and for Wigner's $3j$ symbol. Surprisingly, given that we perform five successive layers of approximations, the asymptotic formula we obtain for $\chi^J(g)$ is in fact exact. This result provides a non trivial example of a Duistermaat-Heckman like localization property for discrete sums.Comment: 36 pages, 3 figure
Asymptotes in SU(2) Recoupling Theory: Wigner Matrices, $3j$ Symbols, and Character Localization
asymptotes in su(2) recoupling theory: wigner matrices, $3j$ symbols, and character localization
employ combining euler maclaurin saddle asymptotic generic wigner derive asymptotic formulae character wigner symbol. surprisingly successive approximations asymptotic exact. trivial duistermaat heckman localization pages
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2126202
10.1007/s00023-010-0074-z
In axial symmetry, there is a gauge for Einstein equations such that the total mass of the spacetime can be written as a conserved, positive definite, integral on the spacelike slices. This property is expected to play an important role in the global evolution. In this gauge the equations reduce to a coupled hyperbolic-elliptic system which is formally singular at the axis. Due to the rather peculiar properties of the system, the local in time existence has proved to resist analysis by standard methods. To analyze the principal part of the equations, which may represent the main source of the difficulties, we study linear perturbation around the flat Minkowski solution in this gauge. In this article we solve this linearized system explicitly in terms of integral transformations in a remarkable simple form. This representation is well suited to obtain useful estimates to apply in the non-linear case.Comment: 13 pages. We suppressed the statements about decay at infinity. The proofs of these statements were incomplete. The complete proofs will require extensive technical analysis. We will studied this in a subsequent work. We also have rewritten the introduction and slighted changed the titl
Linear perturbations for the vacuum axisymmetric Einstein equations
linear perturbations for the vacuum axisymmetric einstein equations
axial einstein spacetime conserved definite spacelike slices. evolution. hyperbolic elliptic formally singular axis. peculiar proved resist methods. analyze principal difficulties perturbation minkowski gauge. solve linearized explicitly transformations remarkable form. suited pages. suppressed statements infinity. proofs statements incomplete. proofs extensive analysis. work. rewritten slighted changed titl
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2131059
10.1007/s00023-011-0076-5
We derive explicit formulae for a set of constraints for the Einstein equations on a null hypersurface, in arbitrary dimensions. We solve these constraints and show that they provide necessary and sufficient conditions so that a spacetime solution of the Cauchy problem on a characteristic cone for the hyperbolic system of the reduced Einstein equations in wave-map gauge also satisfies the full Einstein equations. We prove a geometric uniqueness theorem for this Cauchy problem in the vacuum case.Comment: 83 pages, 1 figur
The Cauchy problem on a characteristic cone for the Einstein equations in arbitrary dimensions
the cauchy problem on a characteristic cone for the einstein equations in arbitrary dimensions
derive formulae einstein hypersurface dimensions. solve spacetime cauchy cone hyperbolic einstein satisfies einstein equations. geometric uniqueness cauchy pages figur
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2104562
10.1007/s00023-011-0079-2
We place further restriction on the possible topology of stationary asymptotically flat vacuum black holes in 5 spacetime dimensions. We prove that the horizon manifold can be either a connected sum of Lens spaces and "handles" $S^1 \times S^2$, or the quotient of $S^3$ by certain finite groups of isometries (with no "handles"). The resulting horizon topologies include Prism manifolds and quotients of the Poincare homology sphere. We also show that the topology of the domain of outer communication is a cartesian product of the time direction with a finite connected sum of $\mathbb R^4,S^2 \times S^2$'s and $CP^2$'s, minus the black hole itself. We do not assume the existence of any Killing vector beside the asymptotically timelike one required by definition for stationarity.Comment: LaTex, 22 pages, 9 figure
Further restrictions on the topology of stationary black holes in five dimensions
further restrictions on the topology of stationary black holes in five dimensions
restriction topology stationary asymptotically holes spacetime dimensions. horizon manifold lens handles quotient isometries handles horizon topologies prism manifolds quotients poincare homology sphere. topology outer cartesian mathbb minus itself. killing beside asymptotically timelike latex pages
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2150295
10.1007/s00023-011-0080-9
Explicit Fermi coordinates are given for geodesic observers comoving with the Hubble flow in expanding Robertson-Walker spacetimes, along with exact expressions for the metric tensors in Fermi coordinates. For the case of non inflationary cosmologies, it is shown that Fermi coordinate charts are global, and space-time is foliated by space slices of constant Fermi (proper) time that have finite extent. A universal upper bound for the proper radius of any leaf of the foliation, i.e., for the proper radius of the spatial universe at any fixed time of the geodesic observer, is given. A general expression is derived for the geometrically defined Fermi relative velocity of a test particle (e.g. a galaxy) comoving with the Hubble flow away from the observer. Least upper bounds of superluminal recessional Fermi velocities are given for spacetimes whose scale factors follow power laws, including matter-dominated and radiation-dominated cosmologies. Exact expressions for the proper radius of any leaf of the foliation for this same class of spacetimes are given. It is shown that the radii increase linearly with proper time of the observer moving with the Hubble flow. These results are applied to particular cosmological models.Comment: This revised version corrects minor typo
Fermi coordinates, simultaneity, and expanding space in Robertson-Walker cosmologies
fermi coordinates, simultaneity, and expanding space in robertson-walker cosmologies
fermi geodesic observers comoving hubble expanding robertson walker spacetimes expressions tensors fermi coordinates. inflationary cosmologies fermi coordinate charts foliated slices fermi proper extent. universal proper leaf foliation i.e. proper universe geodesic observer given. geometrically fermi e.g. comoving hubble away observer. bounds superluminal recessional fermi velocities spacetimes laws dominated dominated cosmologies. expressions proper leaf foliation spacetimes given. radii linearly proper observer moving hubble flow. cosmological revised corrects minor typo
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2139681
10.1007/s00023-011-0082-7
The recent "breakdown criterion" result of S. Klainerman and I. Rodnianski stated roughly that an Einstein-vacuum spacetime, given as a CMC foliation, can be further extended in time if the second fundamental form and the derivative of the lapse of the foliation are uniformly bounded. This theorem and its proof were extended to Einstein-scalar and Einstein-Maxwell spacetimes in the author's Ph.D. thesis. In this paper, we state the main results of the thesis, and we summarize and discuss their proofs. In particular, we will discuss the various issues resulting from nontrivial Ricci curvature and the coupling between the Einstein and the field equations.Comment: 62 pages This version: corrected minor typos, expanded Section 6 (geometry of null cones
On Breakdown Criteria for Nonvacuum Einstein Equations
on breakdown criteria for nonvacuum einstein equations
breakdown criterion klainerman rodnianski stated roughly einstein spacetime foliation lapse foliation uniformly bounded. einstein einstein maxwell spacetimes ph.d. thesis. thesis summarize proofs. nontrivial ricci curvature einstein pages corrected minor typos expanded cones
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2121396
10.1007/s00023-011-0089-0
Quantum field theory on the noncommutative two-dimensional Minkowski space with Grosse-Wulkenhaar potential is discussed in two ways: In terms of a continuous set of generalised eigenfunctions of the wave operator, and directly in position space. In both settings, we find a new type of divergence in planar graphs. It is present at and above the self-dual point. This new kind of divergence might make the construction of a Minkowski space version of the Grosse-Wulkenhaar model impossible.Comment: 26 pages, published versio
Divergences in quantum field theory on the noncommutative two-dimensional Minkowski space with Grosse-Wulkenhaar potential
divergences in quantum field theory on the noncommutative two-dimensional minkowski space with grosse-wulkenhaar potential
noncommutative minkowski grosse wulkenhaar ways generalised eigenfunctions space. settings divergence planar graphs. point. kind divergence minkowski grosse wulkenhaar pages versio
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2138600
10.1007/s00023-011-0090-7
Motivated by recent work of Choquet-Bruhat, Chrusciel, and Martin-Garcia, we prove monotonicity properties and comparison results for the area of slices of the null cone of a point in a Lorentzian manifold. We also prove volume comparison results for subsets of the null cone analogous to the Bishop-Gromov relative volume monotonicity theorem and Guenther's volume comparison theorem. We briefly discuss how these estimates may be used to control the null second fundamental form of slices of the null cone in Ricci-flat Lorentzian four-manifolds with null curvature bounded above.Comment: 16 pages, no figures. Typos fixed. One garbled proof corrected. Published versio
Areas and volumes for null cones
areas and volumes for null cones
motivated choquet bruhat chrusciel martin garcia monotonicity slices cone lorentzian manifold. subsets cone analogous bishop gromov monotonicity guenther theorem. briefly slices cone ricci lorentzian manifolds curvature pages figures. typos fixed. garbled corrected. versio
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2115043
10.1007/s00023-011-0091-6
We prove that the Hamiltonian of the model describing a spin which is linearly coupled to a field of relativistic and massless bosons, also known as the spin-boson model, admits a ground state for small values of the coupling constant lambda. We show that the ground state energy is an analytic function of lambda and that the corresponding ground state can also be chosen to be an analytic function of lambda. No infrared regularization is imposed. Our proof is based on a modified version of the BFS operator theoretic renormalization analysis. Moreover, using a positivity argument we prove that the ground state of the spin-boson model is unique. We show that the expansion coefficients of the ground state and the ground state energy can be calculated using regular analytic perturbation theory
Ground States in the Spin Boson Model
ground states in the spin boson model
describing linearly relativistic massless bosons boson admits lambda. analytic lambda analytic lambda. infrared regularization imposed. theoretic renormalization analysis. positivity argument boson unique. analytic perturbation
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2123643
10.1007/s00023-011-0093-4
We investigate the edge conductance of particles submitted to an Iwatsuka magnetic field, playing the role of a purely magnetic barrier. We also consider magnetic guides generated by generalized Iwatsuka potentials. In both cases we prove quantization of the edge conductance. Next, we consider magnetic perturbations of such magnetic barriers or guides, and prove stability of the quantized value of the edge conductance. Further, we establish a sum rule for edge conductances. Regularization within the context of disordered systems is discussed as well.Comment: 25 page
Quantization of edge currents along magnetic barriers and magnetic guides
quantization of edge currents along magnetic barriers and magnetic guides
conductance submitted iwatsuka playing purely barrier. guides iwatsuka potentials. quantization conductance. perturbations barriers guides quantized conductance. establish conductances. regularization disordered
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2146071
10.1007/s00023-011-0094-3
In this paper the existence of a class of self-similar solutions of the Einstein-Vlasov system is proved. The initial data for these solutions are not smooth, with their particle density being supported in a submanifold of codimension one. They can be thought of as intermediate between smooth solutions of the Einstein-Vlasov system and dust. The motivation for studying them is to obtain insights into possible violation of weak cosmic censorship by solutions of the Einstein-Vlasov system. By assuming a suitable form of the unknowns it is shown that the existence question can be reduced to that of the existence of a certain type of solution of a four-dimensional system of ordinary differential equations depending on two parameters. This solution starts at a particular point $P_0$ and converges to a stationary solution $P_1$ as the independent variable tends to infinity. The existence proof is based on a shooting argument and involves relating the dynamics of solutions of the four-dimensional system to that of solutions of certain two- and three-dimensional systems obtained from it by limiting processes.Comment: 47 page
A class of dust-like self-similar solutions of the massless Einstein-Vlasov system
a class of dust-like self-similar solutions of the massless einstein-vlasov system
einstein vlasov proved. submanifold codimension one. thought einstein vlasov dust. motivation studying insights violation cosmic censorship einstein vlasov system. unknowns ordinary parameters. starts converges stationary tends infinity. shooting argument involves relating limiting
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2143603
10.1007/s00023-011-0096-1
We consider the non-relativistic Hartree model in the gravitational case, i.e. with attractive Coulomb-Newton interaction. For a given mass, we construct stationary states with non-zero temperature by minimizing the corresponding free energy functional. It is proved that minimizers exist if and only if the temperature of the system is below a certain threshold(possibly infinite), which itself depends on the specific choice of the entropy functional. We also investigate whether the corresponding minimizers are mixed or pure quantum states and characterize a positive critical temperature above which mixed states appear
Thermal effects in gravitational Hartree systems
thermal effects in gravitational hartree systems
relativistic hartree gravitational i.e. attractive coulomb newton interaction. stationary minimizing functional. proved minimizers possibly infinite functional. minimizers characterize
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2114168
10.1007/s00023-011-0097-0
In this paper, we prove the following theorem regarding the Wang-Yau quasi-local energy of a spacelike two-surface in a spacetime: Let $\Sigma$ be a boundary component of some compact, time-symmetric, spacelike hypersurface $\Omega$ in a time-oriented spacetime $N$ satisfying the dominant energy condition. Suppose the induced metric on $\Sigma$ has positive Gaussian curvature and all boundary components of $\Omega$ have positive mean curvature. Suppose $H \le H_0$ where $H$ is the mean curvature of $\Sigma$ in $\Omega$ and $H_0$ is the mean curvature of $\Sigma$ when isometrically embedded in $R^3$. If $\Omega$ is not isometric to a domain in $R^3$, then 1. the Brown-York mass of $\Sigma$ in $\Omega$ is a strict local minimum of the Wang-Yau quasi-local energy of $\Sigma$, 2. on a small perturbation $\tilde{\Sigma}$ of $\Sigma$ in $N$, there exists a critical point of the Wang-Yau quasi-local energy of $\tilde{\Sigma}$.Comment: substantially revised, main theorem replaced, Section 3 adde
Critical points of Wang-Yau quasi-local energy
critical points of wang-yau quasi-local energy
quasi spacelike spacetime sigma spacelike hypersurface omega oriented spacetime satisfying condition. sigma curvature omega curvature. curvature sigma omega curvature sigma isometrically embedded omega isometric brown sigma omega strict quasi sigma perturbation tilde sigma sigma quasi tilde sigma .comment substantially revised replaced adde
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2125221
10.1007/s00023-011-0103-6
We provide an explicit combinatorial expansion for the ground state energy of the massless spin-Boson model as a power series in the coupling parameter. Our method uses the technique of cluster expansion in constructive quantum field theory and takes as a starting point the functional integral representation and its reduction to an Ising model on the real line with long range interactions. We prove the analyticity of our expansion and provide an explicit lower bound on the radius of convergence. We do not need multiscale nor renormalization group analysis. A connection to the loop-erased random walk is indicated.Comment: 32 pages, 4 figures, a remark and references added, typos corrected, minor computational errors correcte
The Ground State Energy of The Massless Spin-Boson Model
the ground state energy of the massless spin-boson model
combinatorial massless boson parameter. constructive ising interactions. analyticity convergence. multiscale renormalization analysis. connection erased walk pages remark typos corrected minor correcte
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