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Related papers: Thermostats without conjugate points

200 papers

We introduce a new family of thermostat flows on the unit tangent bundle of an oriented Riemannian $2$-manifold. Suitably reparametrised, these flows include the geodesic flow of metrics of negative Gauss curvature and the geodesic flow…

Differential Geometry · Mathematics 2019-07-19 Thomas Mettler , Gabriel P. Paternain

Several comments are given to previous proofs of the generalised second law of thermodynamics: black hole entropy plus ordinary matter entropy never decreases for a thermally closed system. Arguments in favour of its truism are given in the…

General Relativity and Quantum Cosmology · Physics 2007-05-23 S. -T. Sung

What are appropriate geometric conditions ensuring that a complete Riemannian 2-cylinder without conjugate points is flat? Examples with nonpositive curvature show that one has to assume that the ends of the cylinder open sublinearly. We…

Differential Geometry · Mathematics 2013-10-29 Victor Bangert , Patrick Emmerich

This paper deals with classifying the dynamics of {\it Topologically Anosov} plane homeomorphisms. We prove that a Topologically Anosov homeomorphism $f:\mathbb{R}^2 \to \mathbb{R}^2$ is conjugate to a homothety if it is the time one map of…

Dynamical Systems · Mathematics 2018-05-09 Gonzalo Cousillas , Jorge Groisman , Juliana Xavier

It follows from Oseledec Multiplicative Ergodic Theorem (or Kingman's Sub-additional Ergodic Theorem) that the set of `non-typical' points for which the Oseledec averages of a given continuous cocycle diverge has zero measure with respect…

Dynamical Systems · Mathematics 2015-05-19 Xueting Tian

The present work deals with irreversible Universal thermodynamics. The homogenous and isotropic flat model of the universe is chosen as open thermodynamical system and non-equilibrium thermodynamics comes into picture due to the mechanism…

General Relativity and Quantum Cosmology · Physics 2016-05-17 Subhajit Saha , Atreyee Biswas , Subenoy Chakraborty

In this paper we prove that if the geodesic flow of a {compact or non-compact} complete manifold without conjugate points is of the Anosov type, then the average of the integral of the sectional curvature along the geodesic is negative and…

Dynamical Systems · Mathematics 2019-04-17 Ítalo Melo , Sergio Romaña

In the linear regime, thermo-electric effects between two conductors are possible only in the presence of an explicit breaking of the electron-hole symmetry. We consider a tunnel junction between two electrodes and show that this condition…

Mesoscale and Nanoscale Physics · Physics 2020-03-17 G. Marchegiani , A. Braggio , F. Giazotto

The p-state clock model in two dimensions is a system of discrete rotors with a quasi-liquid phase in a region T1 < T < T2 for p > 4. We show that, for p > 4 and above a temperature Teu, all macroscopic thermal averages, such as energy or…

Statistical Mechanics · Physics 2009-11-11 Cintia M. Lapilli , Peter Pfeifer , Carlos Wexler

Fluctuation theorems specify the non-zero probability to observe negative entropy production, contrary to a naive expectation from the second law of thermodynamics. For closed particle trajectories in a fluid, Stokes theorem can be used to…

Statistical Mechanics · Physics 2022-07-06 Benoît Mahault , Evelyn Tang , Ramin Golestanian

In this paper we consider torus homeomorphisms $f$ homotopic to Dehn twists. We prove that if the vertical rotation set of $f$ is reduced to zero, then there exists a compact connected essential "horizontal" set K, invariant under $f$. In…

Dynamical Systems · Mathematics 2021-02-22 Braulio Garcia , Fabio Armando Tal , Salvador Addas-Zanata

In nature, everything occurs at finite temperature and quantum phase transitions (QPTs) cannot be an exception. Nevertheless, they are still mainly discussed and formulated at zero temperature. We show that the condensation QPTs recently…

Quantum Physics · Physics 2023-08-31 Massimo Ostilli , Carlo Presilla

Let $f$ be a non-invertible partially hyperbolic endomorphism on $\mathbb{T}^2$ which is derived from a non-expanding Anosov endomorphism. Differing from the case of diffeomorphisms derived from Anosov automorphisms, there is no a priori…

Dynamical Systems · Mathematics 2024-09-17 Ruihao Gu , Mingyang Xia

On a real analytic Riemannian manifold a Grauert tube is an uniquely adapted complex structure defined on the tangent bundle. It is called entire if it may be defined on the whole tangent bundle. Here, we show that the geodesic flow of an…

Differential Geometry · Mathematics 2024-10-23 P. Suárez-Serrato

The second law of thermodynamics states that entropy production in macroscopic systems is non-negative, reaching zero only at thermodynamic equilibrium. As a corollary, this implies that the state trajectory of macroscopic systems is…

Statistical Mechanics · Physics 2025-01-30 O. Politano , Alejandro L. Garcia , F. Baras , M. Malek Mansour

Reciprocal relations correlate fairly accurately a great variety of experimental results. Nevertheless, the concepts of statistical fluctuations, and microscopic reversibility - the bases of the accepted proof of the relations by Onsager -…

Chemical Physics · Physics 2007-05-23 Elias P. Gyftopoulos

We show that heat defines a gauge connection on a line bundle over work configurations. Vanishing curvature is equivalent to the local existence of entropy and temperature functions such that heat can be expressed as $TdS$. A conjecture of…

Mathematical Physics · Physics 2026-01-13 Bryan W Roberts

We present fluctuation theorems and moment generating function equalities for generalized thermodynamic observables and quantum dynamics described by completely positive trace preserving (CPTP) maps, with and without feedback control. Our…

Quantum Physics · Physics 2013-10-01 Tameem Albash , Daniel A. Lidar , Milad Marvian , Paolo Zanardi

As the first step in the direction of the Hopf conjecture on the non-existence of metrics with positive sectional curvature on $S^2 \times S^2$ D.Gromoll and K.Tapp in [GT] suggested the following (Weak Hopf) conjecture (on the rigidity of…

Differential Geometry · Mathematics 2007-05-23 Valery Marenich

In this paper, we analyze an abstract thermoelastic system, where the heat conduction follows the Cattaneo law. Zero becomes a spectrum point of the system operator when the coupling and thermal damping parameters of system satisfy specific…

Analysis of PDEs · Mathematics 2024-09-11 Chenxi Deng , Zhong-Jie Han , Zhaobin Kuang , Qiong Zhang