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Related papers: Birthday Inequalities, Repulsion, and Hard Spheres

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We analyze the critical connectivity of systems of penetrable $d$-dimensional spheres having size distributions in terms of weighed random geometrical graphs, in which vertex coordinates correspond to random positions of the sphere centers…

Statistical Mechanics · Physics 2015-08-11 Claudio Grimaldi

A simple analytic theory for mixtures of hard spheres and larger polymers with excluded volume interactions is developed. The mixture is shown to exhibit extensive immiscibility. For large polymers with strong excluded volume interactions,…

Soft Condensed Matter · Physics 2009-11-07 Richard P. Sear

We study the size-topology relations in random packings of dry adhesive polydisperse microspheres with Gaussian and lognormal size distributions through a geometric tessellation. We find that the dependence of the neighbour number on the…

Soft Condensed Matter · Physics 2019-02-20 Wenwei Liu , Sheng Chen , Chuan-yu Wu , Shuiqing Li

In this paper the excluded volume of binary similar hyperparticles with small size difference in D-dimensional Euclidean spaces R2, R3, and R4 is studied using two different statistical geometry approaches. These geometric approaches,…

Soft Condensed Matter · Physics 2026-02-20 H. J. H. Brouwers

In this survey, we discuss volumetric and combinatorial results concerning (mostly finite) intersections or unions of balls (mostly of equal radii) in the $d$-dimensional real vector space, mostly equipped with the Euclidean norm. Our first…

Metric Geometry · Mathematics 2025-12-30 Károly Bezdek , Zsolt Lángi , Márton Naszódi

In this note we solve the ``birthday problem'' for loops on random regular graphs. Namely, for fixed $d\ge 3$, we prove that on a random $d$-regular graph with $n$ vertices, as $n$ approaches infinity, with high probability: (i) almost all…

Combinatorics · Mathematics 2022-09-23 Benjamin Dozier , Jenya Sapir

We develop a theoretical framework and use two-dimensional hydrodynamical simulations to study the repulsive effect between two close orbiters embedded in an accretion disk. We consider orbiters on fixed Keplerian orbits with masses low…

Earth and Planetary Astrophysics · Physics 2024-09-18 F. J. Sanchez-Salcedo , F. S. Masset , S. Cornejo

We prove the first inverse theorem for point--sphere incidence bounds over finite fields in dimensions $d \ge 3$, showing that near-extremality forces algebraic rigidity. While sharp upper bounds have been known for over a decade, the…

Combinatorics · Mathematics 2026-02-12 Shalender Singh , Vishnu Priya Singh

The lower limit on the age of the universe derived from globular cluster dating techniques, which previously strongly motivated a non-zero cosmological constant, has now been dramatically reduced, allowing consistency for a flat matter…

Astrophysics · Physics 2011-02-11 Lawrence M. Krauss

We consider the motion of a discrete random surface interacting by exclusion with a random wall. The heights of the wall at the sites of $\Z^d$ are i.i.d.\ random variables. Fixed the wall configuration, the dynamics is given by the serial…

Probability · Mathematics 2007-05-23 L. R. G. Fontes , M. Vachkovskaia , A. Yambartsev

We study a natural model of random 2-dimensional cubical complex which is a subcomplex of an n-dimensional cube, and where every possible square $2$-face is included independently with probability p. Our main result is to exhibit a sharp…

Combinatorics · Mathematics 2020-09-21 Matthew Kahle , Elliot Paquette , Érika Roldán

When two macromolecules come very near in a fluid, the surrounding molecules, having finite volume, are less likely to get in between. This leads to a pressure difference manifesting as an entropic attraction, called depletion force. Here…

Soft Condensed Matter · Physics 2020-02-26 Nathaniel Rupprecht , Dervis Can Vural

We study an aggregation PDE with competing attractive and repulsive forces on a sphere of arbitrary dimension. In particular, we consider the limit of strongly localized repulsion with a constant attraction term. We prove convergence of…

Analysis of PDEs · Mathematics 2025-12-04 Mark A. Peletier , Anna Shalova

Packing spheres efficiently in large dimension $d$ is a particularly difficult optimization problem. In this paper we add an isotropic interaction potential to the pure hard-core repulsion, and show that one can tune it in order to maximize…

Disordered Systems and Neural Networks · Physics 2018-06-28 Thibaud Maimbourg , Mauro Sellitto , Guilhem Semerjian , Francesco Zamponi

Via numerical simulations and analytical calculations, depletion forces are studied in mixtures of small and big particles that interact via soft repulsive potentials. While big particles are spherical, small particles are nonspherical with…

Soft Condensed Matter · Physics 2024-09-13 Itay Azizi

We present a numerical study of the effect that fluid and particle inertia have on the motion of suspended spherical particles through a geometric constriction to understand analogous microfluidic settings, such as pinched flow…

Fluid Dynamics · Physics 2013-06-20 Sumedh R. Risbud , Mingxiang Luo , Joelle Frechette , German Drazer

We investigate the response of a system of hard spheres to two classes of perturbations over a range of densities spanning the fluid, crystalline, and glassy regimes within a molecular dynamics framework. Firstly, we consider the relaxation…

Statistical Mechanics · Physics 2025-09-04 Matthew Kafker , Xerxes D. Arsiwalla

In dense, static, polydisperse granular media under isotropic pressure, the probability density and the correlations of particle-wall contact forces are studied. Furthermore, the probability density functions of the populations of pressures…

Statistical Mechanics · Physics 2009-12-15 Stefan Luding , Micha-Klaus Mueller , Thorsten Poeschel

We introduce a fun problem that can be considered as a variant of the classic birthday problem, the Bottleneck Birthday Problem (BBP). It is stated as: what is the maximum number of people we have to choose so that no day of the year has…

Discrete Mathematics · Computer Science 2026-05-01 Chijul B. Tripathy

Embedding graphs in a geographical or latent space, i.e.\ inferring locations for vertices in Euclidean space or on a smooth manifold or submanifold, is a common task in network analysis, statistical inference, and graph visualization. We…

Computational Geometry · Computer Science 2022-05-18 Varsha Dani , Josep Díaz , Thomas P. Hayes , Cristopher Moore