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We establish unweighted Hardy-type inequalities on step-two Carnot groups with one-dimensional vertical layer, with explicit lower bounds for the optimal Hardy constant. The approach is based on a quantitative integration-by-parts mechanism…

Analysis of PDEs · Mathematics 2026-03-05 Lorenzo d'Arca , Luca Fanelli , Valentina Franceschi , Dario Prandi

We provide a simple, combinatorial criteria for a hierarchically hyperbolic space to be relatively hyperbolic by proving a new formulation of relative hyperbolicity in terms of hierarchy structures. In the case of clean hierarchically…

Geometric Topology · Mathematics 2020-07-16 Jacob Russell

In this paper we provide new characterizations of the Gehring-Hayman theorem from the point of view of Gromov boundary and uniformity. We also determine the critical exponents for the uniformized space to be a uniform space in the case of…

Metric Geometry · Mathematics 2022-02-03 Sari Rogovin , Hyogo Shibahara , Qingshan Zhou

Bell's inequality plays an important role with respect to the Einsteinian question about the physical reality of quantum theory. While Bell's inequality is usually viewed within the geometric framework of a Hilbert space quantum model, the…

Quantum Physics · Physics 2023-04-26 Ulrich Faigle

This review examines classical and recent results on controllability and inverse problems for hyperbolic and dispersive equations with dynamic boundary conditions. We aim to illustrate the applicability of Carleman estimates to establish…

Optimization and Control · Mathematics 2025-05-22 S. E. Chorfi , L. Maniar , R. Morales

We prove a refinement of the inequality by Hoffmann-Jorgensen that is significant for three reasons. First, our result improves on the state-of-the-art even for real-valued random variables. Second, the result unifies several versions in…

Probability · Mathematics 2017-11-29 Apoorva Khare , Bala Rajaratnam

We study the connection between the $p$--Talagrand inequality and the $q$--logarithmic Sololev inequality for conjugate exponents $p\geq 2$, $q\leq 2$ in proper geodesic metric spaces. By means of a general Hamilton--Jacobi semigroup we…

Functional Analysis · Mathematics 2009-06-03 Zoltan Balogh , Alexandre Engoulatov , Lars Hunziker , Outi Elina Maasalo

This paper is a second one following our work [CLZ13] in series, considering sharp Hardy- Littlewood-Sobolev inequalities on groups of Heisenberg type. The first important breakthrough was made by Frank and Lieb in [FL12]. In this paper,…

Functional Analysis · Mathematics 2014-07-15 Michael Christ , Heping Liu , An Zhang

We develop the theory of Patterson-Sullivan measures on the boundary of a locally compact hyperbolic group, associating to certain left invariant metrics on the group measures on the boundary. We later prove that for second countable,…

Group Theory · Mathematics 2023-09-25 Michael Glasner

We prove quantitative stability of isometries on the first Heisenberg group with sub-Riemannian geometry: every $ (1+ \varepsilon)$-quasi-isometry of the John domain of the Heisenberg group $ \mathbb {H} $ is close to some isometry with…

Functional Analysis · Mathematics 2022-05-06 Daria Isangulova

This paper aims to define and study currents and slices of currents in the Heisenberg group $\mathbb{H}^n$. Currents, depending on their integration properties and on those of their boundaries, can be classified into subspaces and, assuming…

Differential Geometry · Mathematics 2020-07-03 Giovanni Canarecci

Given a finite collection of $C^1$ complex vector fields on a $C^2$ manifold $M$ such that they and their complex conjugates span the complexified tangent space at every point, the classical Newlander-Nirenberg theorem gives conditions on…

Complex Variables · Mathematics 2020-04-13 Brian Street

We generalise in this article the Mc Shane-Mirzakhani identities in hyperbolic geometry to arbitrary cross ratios. We give an expression of them in the case of Hitchin representations of surface groups in PSL(n, R) in a suitable choice of…

Differential Geometry · Mathematics 2019-12-19 F. Labourie , G. McShane

We generalize a result of Paulin on the Gromov boundary of hyperbolic groups to the Morse boundary of proper, maximal hierarchically hyperbolic spaces admitting cocompact group actions by isometries. Namely we show that if the Morse…

Geometric Topology · Mathematics 2018-01-16 Sarah C. Mousley , Jacob Russell

In Phys. Rev. A 70, 032104 (2004), M. Montesinos and G. F. Torres del Castillo consider various symplectic structures on the classical phase space of the two-dimensional isotropic harmonic oscillator. Using Dirac's quantization condition,…

Quantum Physics · Physics 2009-11-13 D. C. Latimer

We study combinatorial modulus on boundaries of hyperbolic Coxeter groups. We give new examples of hyperbolic groups whose boundary satisfies a combinatorial version of the Loewner property, and prove Cannon's conjecture for Coxeter groups.…

Group Theory · Mathematics 2011-05-04 Marc Bourdon , Bruce Kleiner

We explore for compact Riemannian surfaces whose boundary consists of a single closed geodesic the relationship between orthospectrum and boundary length. More precisely, we establish a uniform lower bound on the boundary length in terms of…

Differential Geometry · Mathematics 2025-03-04 Florent Balacheff , David Fisac

We prove an invariant Harnack's inequality for operators in non-divergence form structured on Heisenberg vector fields when the coefficient matrix is uniformly positive definite, continuous, and symplectic. The method consists in…

Analysis of PDEs · Mathematics 2017-06-01 Farhan Abedin , Cristian E. Gutiérrez , Giulio Tralli

In physics, two systems that radically differ at short scales can exhibit strikingly similar macroscopic behaviour: they are part of the same long-distance universality class. Here we apply this viewpoint to geometry and initiate a program…

High Energy Physics - Theory · Physics 2023-11-22 Adam R. Brown , Michael H. Freedman , Henry W. Lin , Leonard Susskind

For a hyponormal operator, C. R. Putnam's inequality gives an upper bound on the norm of its self-commutator. In the special case of a Toeplitz operator with analytic symbol in the Smirnov space of a domain, there is also a geometric lower…

Functional Analysis · Mathematics 2014-11-13 Steven R. Bell , Timothy Ferguson , Erik Lundberg