English
Related papers

Related papers: Ensemble inequivalence: A formal approach

200 papers

We demonstrate that the presence of entanglement in macroscopic bodies (e.g. solids) in thermodynamical equilibrium could be revealed by measuring heat-capacity. The idea is that if the system were in a separable state, then for certain…

Quantum Physics · Physics 2008-08-14 Marcin Wiesniak , Vlatko Vedral , Caslav Brukner

We propose a new approach to justify the use of the microcanonical ensemble for isolated macroscopic quantum systems. Since there are huge number of independent observables in a macroscopic system, we cannot see all of them. Actually what…

Statistical Mechanics · Physics 2008-02-25 Ayumu Sugita

In contrast to the canonical case, microcanonical thermodynamic functions can show nonanalyticities also for finite systems. In this paper we contribute to the understanding of these nonanalyticities by working out the relation between…

Statistical Mechanics · Physics 2009-07-22 Lapo Casetti , Michael Kastner , Rachele Nerattini

Interacting particle systems are in frequent use to model collective behaviour in various situations and applications. For many systems, the interaction between the agents is restricted to an underlying network structure and often, the…

Analysis of PDEs · Mathematics 2025-07-30 Sebastian Throm

Recent experimental results point to the existence of coherent quantum phenomena in systems made of a large number of particles, despite the fact that for many-body systems the presence of decoherence is hardly negligible and emerging…

Quantum Physics · Physics 2017-09-21 F. Benatti , F. Carollo , R. Floreanini , H. Narnhofer

Heat capacities of model systems with finite numbers of effective degrees of freedom are evaluated using canonical and microcanonical thermodynamics. Discrepancies between both approaches, which are observed even in the infinite-size limit,…

Quantum Physics · Physics 2017-02-16 Pavel Cejnar , Pavel Stránský

We establish an analytical criterion for dynamical thermalization within harmonic systems, applicable to both classical and quantum models. Specifically, we prove that thermalization of various observables, such as particle energies in…

Statistical Mechanics · Physics 2025-07-29 Marco Cattaneo , Marco Baldovin , Dario Lucente , Paolo Muratore-Ginanneschi , Angelo Vulpiani

The relationship between classical and quantum mechanics is usually understood via the limit $\hbar \rightarrow 0$. This is the underlying idea behind the quantization of classical objects. The apparent incompatibility of general relativity…

Quantum Physics · Physics 2021-03-15 J. -B. Bru , W. de Siqueira Pedra

We introduce a simple model of hard spheres with gravitational interactions, for which we study a suitable scaling limit. Usual extensive properties are maintained notwithstanding the long range of gravitational interaction. We show that a…

Statistical Mechanics · Physics 2015-03-31 Maxime Champion , Angel Alastuey , Thierry Dauxois , Stefano Ruffo

Microcanonical thermodynamics (MCTh) is contrasted to canonical thermodynamics (CTh). At phase transitions of 1.order the two ensembles are NOT equivalent even in the thermodynamic limit . Energy fluctuations do not vanish and phase…

Statistical Mechanics · Physics 2007-05-23 D. H. E. Gross

The positivity of the heat capacity is the hallmark of thermal stability of systems in thermodynamic equilibrium. We show that this property remains valid for systems with negative derivative of energy with respect to temperature, as…

Statistical Mechanics · Physics 2020-06-24 Mário J. de Oliveira

We consider the critical behavior at an interface which separates two semi-infinite subsystems belonging to different universality classes, thus having different set of critical exponents, but having a common transition temperature. We…

Statistical Mechanics · Physics 2007-05-23 F. A. Bagamery , L. Turban , F. Igloi

Active systems, which are driven out of equilibrium by local non-conservative forces, exhibit unique behaviors and structures with potential utility for the design of novel materials. An important and difficult challenge along the path…

Soft Condensed Matter · Physics 2022-08-09 Laura Tociu , Gregory Rassolov , Étienne Fodor , Suriyanarayanan Vaikuntanathan

The microcanonical ensemble is in important physical situations different from the canonical one even in the thermodynamic limit. In contrast to the canonical ensemble it does not suppress spatially inhomogeneous configurations like phase…

Condensed Matter · Physics 2007-05-23 D. H. E. Gross , M. E. Madjet

A quantum microcanonical postulate is proposed as a basis for the equilibrium properties of small quantum systems. Expressions for the corresponding density of states are derived, and are used to establish the existence of phase transitions…

Quantum Physics · Physics 2007-06-13 Dorje C. Brody , Daniel W. Hook , Lane P. Hughston

An instructive and apparently simple model of fully-coupled rotators, the so-called Hamiltonian Mean Field (HMF) model, together with a generalized version with variable interaction range, have revealed a very complex out-of-equilibrium…

Statistical Mechanics · Physics 2015-06-25 Andrea Rapisarda , Alessandro Pluchino

We present a complete analytical solution of a system of Potts spins on a random k-regular graph in both the canonical and microcanonical ensembles, using the Large Deviation Cavity Method (LDCM). The solution is shown to be composed of…

Statistical Mechanics · Physics 2009-11-13 Julien Barre , Bruno Goncalves

The thermodynamics of the discrete nonlinear Schr\"odinger equation in the vicinity of infinite temperature is explicitly solved in the microcanonical ensemble by means of large-deviation techniques. A first-order phase transition between a…

Statistical Mechanics · Physics 2021-06-08 Giacomo Gradenigo , Stefano Iubini , Roberto Livi , Satya N. Majumdar

Theoretical work has shed light on the phase behavior of idealized mixtures of many components with random interactions. But typical mixtures interact through particular physical features, leading to a structured, non-random interaction…

Statistical Mechanics · Physics 2022-09-05 Isabella R. Graf , Benjamin B. Machta

An analytical method to compute thermodynamic properties of a given Hamiltonian system is proposed. This method combines ideas of both dynamical systems and ensemble approaches to thermodynamics, providing de facto a possible alternative to…

Statistical Mechanics · Physics 2009-10-31 Xavier Leoncini , Alberto D. Verga