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Related papers: Hopf type rigidity for thermostats

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Let H(q,p) = p^2/2 + V(q) be a 1-degree of freedom mechanical Hamiltonian with a C^n periodic potential V where n>4. The Nos\'e-thermostated system associated to H is shown to have invariant tori near the infinite temperature limit. This is…

Dynamical Systems · Mathematics 2017-02-09 Leo T. Butler

Angle and temperature dependent torque magnetization measurements are reported for the organic superconductor kappa-(BEDT-TTF)2Cu(NCS)2, at extremely low temperatures (approx. Tc/10^3). Magneto-thermal instabilities are observed in the form…

Superconductivity · Physics 2007-05-23 M. M. Mola , S. Hill , J. S. Brooks , J. S. Qualls

Electrical-resistivity and magnetic-susceptibility measurements under hydrostatic pressure up to p = 2.75 GPa have been performed on superconducting LiFeP. A broad superconducting (SC) region exists in the temperature - pressure (T-p) phase…

Superconductivity · Physics 2010-07-14 K. Mydeen , E. Lengyel , Z. Deng , X. C. Wang , C. Q. Jin , M. Nicklas

Our research is directed to a quasi-static evolution of the thermo-visco-elastic model. We assume that the material is subject to two kinds of mechanical deformations: elastic and inelastic. Moreover, our analysis captures the influence of…

Analysis of PDEs · Mathematics 2014-04-08 Piotr Gwiazda , Filip Z. Klawe , Agnieszka Świerczewska-Gwiazda

In this paper, we give a complete topological and smooth classification of non-invertible Anosov maps on torus. We show that two non-invertible Anosov maps on torus are topologically conjugate if and only if their corresponding periodic…

Dynamical Systems · Mathematics 2026-01-14 Ruihao Gu , Yi Shi

Let $T= S^1\times D^2$ be the solid torus, $\mathcal{F}$ the Morse-Bott foliation on $T$ into $2$-tori parallel to the boundary and one singular circle $S^1\times 0$, which is the central circle of the torus $T$, and…

Algebraic Topology · Mathematics 2024-01-22 Oleksandra Khokhliuk , Sergiy Maksymenko

This paper is primarily devoted to the study of Hopf heaps and Hopf heap modules. We redefine the structure of Hopf trusses by means of Hopf heaps, establish the connection between Hopf trusses and Hopf braces, and provide a series of…

Rings and Algebras · Mathematics 2026-02-10 Huihui Zheng , Chan Zhao , Liangyun Zhang

In this article, we determine cocycle deformations and Galois objects of non-commutative and non-cocommutative semisimple Hopf algebras of dimension $16$. We show that these Hopf algebras are pairwise twist inequivalent mainly by…

Representation Theory · Mathematics 2022-09-05 Rongchuan Xiong , Zhiqiang Yu

Using the methods of moving frames and exterior differential systems, we show that there exist Hopf hypersurfaces in complex hyperbolic space CH^2 with any specified value of the Hopf principal curvature less than or equal to the…

Differential Geometry · Mathematics 2008-12-25 Thomas A. Ivey , Patrick J. Ryan

We prove there is only one involution (up to conjugacy) on the n-torus which acts as $-\mathrm{Id}$ on the first homology group when $n$ is of the form $4k$, is of the form $4k+1$, or is less than $4$. In all other cases we prove there are…

Geometric Topology · Mathematics 2014-11-11 Frank Connolly , James F. Davis , Qayum Khan

There are now many nodal superconductors in heavy fermion (HF) systems, charge conjugated organic metals, high Tc cuprates and ruthenates. On the other hand only few of them have a well established gap function. We present here a study of…

Superconductivity · Physics 2018-02-02 P. Thalmeier , K. Maki

Transformation of operator algebras under Hopf algebra twist is studied. It is shown that that adjoint module algebras are stable under the twist. Applications to vector fields on non-commutative space-time are considered.

Quantum Algebra · Mathematics 2015-05-20 Petr Kulish , Andrey Mudrov

We obtain Margulis-type asymptotic estimates for the number of free homotopy classes of closed geodesics on certain manifolds without conjugate points. Our results cover all compact surfaces of genus at least 2 without conjugate points.

Dynamical Systems · Mathematics 2021-05-25 Vaughn Climenhaga , Gerhard Knieper , Khadim War

One-variable thermostats are studied as a generalization of the Nos\'e--Hoover method which is aimed to achieve Gibbs' canonical distribution with conserving the time-reversibility. A condition for equations of motion for the system with…

Statistical Mechanics · Physics 2015-06-25 Hiroshi Watanabe , Hiroto Kobayashi

A Hopf Galois structure on a finite field extension $L/K$ is a pair $(\mathcal{H},\mu)$, where $\mathcal{H}$ is a finite cocommutative $K$-Hopf algebra and $\mu$ a Hopf action. In this paper, we present several results on Hopf Galois…

Group Theory · Mathematics 2019-06-11 Teresa Crespo , Marta Salguero

Non-Fermi-liquid features of the high-Tc cuprates, and specifically the systematic behavior of the resistivity, Hall constant, and thermoelectric power, are shown to result from an electronic structure based on "large-U" and "small-U"…

Superconductivity · Physics 2009-10-30 J. Ashkenazi

We introduce non-abelian cohomology sets of Hopf algebras with coefficients in Hopf modules. We prove that these sets generalize Serre's non-abelian group cohomology theory. Using descent techniques, we establish that our construction…

K-Theory and Homology · Mathematics 2007-05-23 Philippe Nuss , Marc Wambst

We combine results available in the literature to prove that the torus emerging in a secondary Hopf bifurcation is normally hyperbolic. This result is then applied to establish sufficient conditions for the bifurcation of normally…

Dynamical Systems · Mathematics 2025-07-16 Pedro C. C. R. Pereira , Douglas D. Novaes

We prove antisymmetric maximum principles and Hopf-type lemmas for linear problems described by the Logarithmic Laplacian. As application, we prove the symmetry of solutions for semilinear problems in symmetric sets, and a rigidity result…

Analysis of PDEs · Mathematics 2024-07-17 Luigi Pollastro , Nicola Soave

The paper is devoted to the study of homotopy properties of stabilizers of smooth functions on oriented surfaces, i.e., groups of diffeomorphisms of surfaces preserving a given function. For some class of smooth functions which is a…

Geometric Topology · Mathematics 2026-05-06 Bohdan Feshchenko