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Related papers: Ptolemy constant and uniformity

200 papers

The evolution of inhomogeneities in a spherical collapse model is studied by expanding the Einstein equation in powers of inverse radial parameter. In the linear regime, the density contrast is obtained for flat, closed and open universes.…

Astrophysics · Physics 2008-11-26 Elcio Abdalla , Roya Mohayaee

We consider a nonlocal equation set in an unbounded domain with the epigraph property. We prove symmetry, monotonicity and rigidity results. In particular, we deal with halfspaces, coercive epigraphs and epigraphs that are flat at infinity.

Analysis of PDEs · Mathematics 2016-10-26 Serena Dipierro , Nicola Soave , Enrico Valdinoci

We consider positive one-dimensional solutions of a Lane-Emden relative Dirichlet problem in a cylinder and study their stability/instability properties as the energy varies with respect to domain perturbations. This depends on the exponent…

Analysis of PDEs · Mathematics 2025-11-25 Francesca De Marchis , Lisa Mazzuoli , Filomena Pacella

Ptolemy-s planetary model is an ancient geocentric astronomical model, describing the observed motion of the Sun and the planets. Ptolemy accounted for the deviations of planetary orbits from perfect circles by introducing two small and…

History and Philosophy of Physics · Physics 2015-03-11 Ilia Rushkin

We present some constructions that are merely the fruit of combining recent results from two areas of smooth dynamics: nonuniformly hyperbolic systems and elliptic constructions.

Dynamical Systems · Mathematics 2007-05-23 Bassam Fayad

Stability of some solutions of the equations of motion of bosonic p-branes in curved and flat spacetimes is stated.

High Energy Physics - Theory · Physics 2010-04-06 P. Demkin

Finite frames can be viewed as mass points distributed in $N$-dimensional Euclidean space. As such they form a subclass of a larger and rich class of probability measures that we call probabilistic frames. We derive the basic properties of…

Probability · Mathematics 2017-09-04 Martin Ehler , Kasso A. Okoudjou

We study the dynamics of small fluctuations about the uniform state of a crystal moving through a dissipative medium, e.g. a sedimenting colloidal crystal or a moving flux lattice, using a set of continuum equations for the displacement…

Condensed Matter · Physics 2009-10-28 Rangan Lahiri , Sriram Ramaswamy

Static equilibrium configurations of continua supported by surface tension are given by constant mean curvature (CMC) surfaces which are critical points of a variational problem to extremize the area while keeping the volume fixed. CMC…

Mathematical Physics · Physics 2023-12-05 Miyuki Koiso , Umpei Miyamoto

We study stable rationality properties of conic bundles over rational surfaces.

Algebraic Geometry · Mathematics 2015-03-31 Brendan Hassett , Andrew Kresch , Yuri Tschinkel

We discuss the fundamental constants of physics in the Standard Model and possible changes of these constants on the cosmological time scale. The Grand Unification of the strong, electromagnetic and weak interactions implies relations…

High Energy Physics - Phenomenology · Physics 2009-07-22 H. Fritzsch

A continuum theory is used to predict scaling laws for the morphological relaxation of crystal surfaces in two independent space dimensions. The goal is to unify previously disconnected experimental observations of decaying surface…

Materials Science · Physics 2009-11-13 Dionisios Margetis

This article is devoted to the study of mappings defined in the region on the plane. Under certain conditions, the upper estimate of the distortion of the modulus of families of paths is obtained. Similarly, the upper estimate of the…

Complex Variables · Mathematics 2022-07-22 E. Sevost'yanov , V. Targonskii

In this paper, we study the stability of the concentration inequality for one-dimensional complex polynomials. We provide the stability of the local concentration inequality and a global version using a Wehrl-type entropy.

Classical Analysis and ODEs · Mathematics 2025-06-18 María Ángeles García-Ferrero , Joaquim Ortega-Cerdà

Three results in p-convex geometry are established. First is the analogue of the Levi problem in several complex variables, namely: local p-convexity implies global p-convexity. The second asserts that the support of a minimal p-dimensional…

Differential Geometry · Mathematics 2017-12-12 F. Reese Harvey , H. Blaine Lawson

Spaces of quasi-invariant measures supplied with different topologies are studied. Their embeddings, projective decompositions, conditions for their metrizability are investigated. Theorems about convergence of nets of quasi-invariant…

Probability · Mathematics 2016-06-08 Sergey Victor Ludkowski

The stability of transparent spherically symmetric thin shells (and wormholes) to linearized spherically symmetric perturbations about static equilibrium is examined. This work generalizes and systematizes previous studies and explores the…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Mustapha Ishak , Kayll Lake

We investigate the growth of the constants of the polynomial Hardy-Littlewood inequality.

Various contributions to the cosmological constant are discussed and confronted with its recent measurement. We briefly review different scenarious -- and their difficulties -- for a solution of the cosmological constant problem.

High Energy Physics - Phenomenology · Physics 2017-08-23 U. Ellwanger

The idea of monotonicity (or positive-definiteness in the linear case) is shown to be the central theme of the solution theories associated with problems of mathematical physics. A "grand unified" setting is surveyed covering a…

Analysis of PDEs · Mathematics 2014-06-19 Rainer Picard , Sascha Trostorff , Marcus Waurick