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Related papers: Orbit Equivalence and Measured Group Theory

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In the study of walks with small steps confined to multidimensional orthants, a certain group of transformations plays a central role. In particular, several techniques to potentially compute the generating function, including the orbit sum…

Combinatorics · Mathematics 2026-01-01 Andrew Elvey Price , Emmanuel Humbert , Kilian Raschel

We develop a semigroup approach to representation theory for pro-Lie groups satisfying suitable amenability conditions. As an application of our approach, we establish a one-to-one correspondence between equivalence classes of unitary…

Representation Theory · Mathematics 2016-06-07 Daniel Beltita , Amel Zergane

We study the realization problem of finite groups as the group of homotopy classes of self-homotopy equivalences of finite spaces. Let $G$ be a finite group. Using an infinite family of pairwise non weakly homotopic asymmetric spaces we…

Algebraic Topology · Mathematics 2025-02-27 Juan Felipe Celis-Rojas

For a geometrically finite group Gamma of G=SO(n,1), we survey recent developments on counting and equidistribution problems for orbits of Gamma in a homogeneous space H\G where H is trivial, symmetric or horospherical. Main applications…

Number Theory · Mathematics 2014-04-08 Hee Oh

A complete theory of overmeasurement by measuring refinements of observables is presented. It encompasses a wider set of functions of observ- ables (coarsenings) . Thus the theory has a broad potential application.It is applied to a…

Quantum Physics · Physics 2015-11-24 Fedor Herbut

We settle some open problems in the special case of groups in o-minimal structures, such as the equality of G^00 and G^000 and the equivalence of definable amenability and existence of a type with bounded orbit. We prove almost exactness of…

Logic · Mathematics 2011-01-11 Anand Pillay

It is proven that the orbit-equivalence class of any essentially free probability-measure-preserving action of a free group $G$ is weakly dense in the space of actions of $G$.

Dynamical Systems · Mathematics 2013-08-15 Lewis Bowen

The famous equivalence theorem is reexamined in order to make it applicable to the case of intrinsically quantum infinite-component effective theories. We slightly modify the formulation of this theorem and prove it basing on the notion of…

High Energy Physics - Theory · Physics 2013-05-29 D. Chicherin , V. Gorbenko , V. Vereshagin

We develop a theory of large scale geometry of metrisable topological groups that, in a significant number of cases, allows one to define and identify a unique quasi-isometry type intrinsic to the topological group. Moreover, this…

Group Theory · Mathematics 2014-03-14 Christian Rosendal

A higher order theory of gravitation is considered which is obtained by modifying Einstein field equations. The Lagrange used to modify this in the form a polynomial in (scalar curvature) R. In this equation we have studied spherical…

General Relativity and Quantum Cosmology · Physics 2009-11-04 S. N. Pandey , B. K. Sinha

We show that a finite unitary group which has orbits spanning the whole space is necessarily the setwise stabilizer of a certain orbit.

Group Theory · Mathematics 2019-01-29 Erik Friese

We prove that the full automorphism group and the outer automorphism group of the free group of countably infinite rank are coarsely bounded. That is, these groups admit no continuous actions on a metric space with unbounded orbits, and…

Group Theory · Mathematics 2023-04-11 George Domat , Hannah Hoganson , Sanghoon Kwak

Axiomatic approach to measurement theory is developed. All the possible statistical properties of apparatuses measuring an observable with nondegenerate spectrum allowed in standard quantum mechanics are characterized.

Quantum Physics · Physics 2007-05-23 Masanao Ozawa

This is a short, self-contained expository survey, focused on algebraic and analytic aspects of quantum groups. Topics covered include the definition of ``quantum group,'' the Yang-Baxter equation, quantized universal enveloping algebras,…

Quantum Algebra · Mathematics 2007-05-23 William Gordon Ritter

In this survey, we describe recent progress on asymptotic properties of various automorphic orbits in free groups. In particular, we address the problem of counting potentially positive elements of a given length. We also discuss complexity…

Group Theory · Mathematics 2025-10-09 Vladimir Shpilrain

The theory of measurement is employed to elucidate the physical basis of general relativity. For measurements involving phenomena with intrinsic length or time scales, such scales must in general be negligible compared to the (translational…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Bahram Mashhoon

This is a survey, intended both for group theorists and model theorists, concerning the structure of pseudofinite groups, that is, infinite models of the first order theory of finite groups. The focus is on concepts from stability theory…

Logic · Mathematics 2016-07-25 Dugald Macpherson

We consider the construction of gauge theories of gravity that are invariant under local conformal transformations. We first clarify the geometric nature of global conformal transformations, in both their infinitesimal and finite forms, and…

General Relativity and Quantum Cosmology · Physics 2022-01-10 Michael Hobson , Anthony Lasenby

We prove a measurable version of the Hall marriage theorem for actions of finitely generated abelian groups. In particular, it implies that for free measure-preserving actions of such groups, if two equidistributed measurable sets are…

Logic · Mathematics 2021-07-08 Tomasz Cieśla , Marcin Sabok

We explore quantum measurement in the context of Everettian unitary quantum mechanics and construct an explicit unitary measurement procedure. We propose the existence of prior correlated states that enable this procedure to work and…

Quantum Physics · Physics 2024-01-08 Vishal Johnson , Philipp Frank , Torsten Enßlin