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Nowadays, nonhomogeneous and periodic ferromagnetic materials are the subject of a growing interest. Actually such periodic configurations often combine the attributes of the constituent materials, while sometimes, their properties can be…

Analysis of PDEs · Mathematics 2016-02-17 François Alouges , Giovanni Di Fratta

This study combines theoretical advancements with observational limitations to investigate the cosmological implications of a bulk viscous modified Chaplygin gas (MCG) in a Friedmann--Robertson--Walker (FRW) in (3+1) dimensional spacetime…

General Relativity and Quantum Cosmology · Physics 2025-12-23 Mohit Thakre , Praveen Kumar Dhankar , Behnam Pourhassan , Safiqul Islam

We study in this paper compression effects in heterogeneous media with maximal packing constraint. Starting from compressible Brinkman equations, where maximal packing is encoded in a singular pressure and a singular bulk viscosity, we show…

Analysis of PDEs · Mathematics 2018-07-18 D. Bresch , S. Necasova , C. Perrin

Electromagnetic materials with a uniaxial effective permittivity tensor, characterized by its transverse ($\epsilon_\perp$) and axial ($\epsilon_\parallel$) components, play a central role in the design of advanced photonic and…

Optics · Physics 2025-07-15 Kshiteej J. Deshmukh , Graeme W. Milton

In this paper we review the recent advances which have taken place in the understanding and applications of acoustic/elastic metamaterials. Metamaterials are artificially created composite materials which exhibit unusual properties which…

Materials Science · Physics 2015-02-12 Ankit Srivastava

The Muttalib-Borodin biorthogonal ensemble is a probability density function for $n$ particles on the positive real line that depends on a parameter $\theta$ and an external field $V$. For $\theta=\frac{1}{2}$ we find the large $n$ behavior…

Classical Analysis and ODEs · Mathematics 2022-07-06 A. B. J. Kuijlaars , L. D. Molag

We prove that in various natural models of a random quotient of a group, depending on a density parameter, for each hyperbolic group there is some critical density under which a random quotient is still hyperbolic with high probability,…

Group Theory · Mathematics 2007-05-23 Yann Ollivier

We consider the gravitational collapse of self-gravitating spherical dust cloud in the Hamiltonian formalism. We address both homogeneous and inhomogeneous cases. Our novel derivation of the Hamiltonian of the system is based on the…

General Relativity and Quantum Cosmology · Physics 2020-05-13 Nick Kwidzinski , Daniele Malafarina , Jan Ostrowski , Włodzimierz Piechocki , Tim Schmitz

We perform a systematic study of the thermodynamics of quantum gases in the unitarity limit. Our study makes use of a "Universality Hypothesis" for the relevant energy scales of a many-body system at unitarity. This Hypothesis is supported…

Condensed Matter · Physics 2011-07-19 Tin-Lun Ho

We present semi-analytical constraint on the amount of dark matter in the merging bullet galaxy cluster using the classical Local Group timing arguments. We consider particle orbits in potential models which fit the lensing data. {\it…

Astrophysics · Physics 2007-05-23 HongSheng Zhao

Sub-wavelength nanostructured systems with tunable electromagnetic properties, such as hyperbolic metamaterials (HMMs), provide a useful platform to tailor spontaneous emission processes. Here, we investigate a system comprising $Eu^{…

This paper develops the a priori analysis of a mixed finite element method for the filtration of an incompressible fluid through a non-deformable saturated porous medium with heterogeneous permeability. Flows are governed by the…

Numerical Analysis · Mathematics 2023-01-25 Sergio Caucao , Marco Discacciati

We consider the model of viscous compressible homogeneous multi-fluids with multiple velocities. We review different formulations of the model and the existence results for boundary value problems. We analyze crucial mathematical…

Analysis of PDEs · Mathematics 2016-10-19 Alexander Mamontov , Dmitriy Prokudin

Peridynamics provides a versatile tool for fracture modelling in materials where fracture pathways cannot be predicted beforehand, but must be envisaged as an emergent features of the deformation process. One class of materials where this…

Materials Science · Physics 2025-12-18 Shucheta Shegufta , Michael Zaiser

The use of powerful hydrogen cluster jet targets in storage ring experiments led to the need of precise data on the mean cluster velocity as function of the stagnation temperature and pressure for the determination of the volume density of…

Atomic and Molecular Clusters · Physics 2014-01-07 Alexander Täschner , Esperanza Köhler , Hans-Werner Ortjohann , Alfons Khoukaz

We develop a new formalism for the treatment of gravitational backreaction in the cosmological setting. The approach is inspired by projective techniques in non-equilibrium statistical mechanics. We employ group-averaging with respect to…

General Relativity and Quantum Cosmology · Physics 2009-11-06 Charis Anastopoulos

Let M be a smooth complex projective variety, bearing a K\"ahler symplectic form \omega and a Hamiltonian action of a torus T, with finitely many fixed points M^T. One standard form of the Duistermaat-Heckman theorem gives a formula for M's…

Symplectic Geometry · Mathematics 2022-02-04 Allen Knutson

We obtain estimates of all components of the velocity of a 3D rigid body moving in a viscous incompressible fluid without any symmetry restriction on the shape of the rigid body or the container. The estimates are in terms of suitable norms…

Analysis of PDEs · Mathematics 2023-04-25 Stathis Filippas , Alkis Tersenov

The goal of this contribution is to introduce the Hamiltonian formalism of theoretical mechanics for analysing motion in generic linear and non-linear dynamical systems, including particle accelerators. This framework allows the derivation…

Accelerator Physics · Physics 2024-02-27 Yannis Papaphilippou

This article continues our previous study of generalized Forchheimer flows in heterogeneous porous media. Such flows are used to account for deviations from Darcy's law. In heterogeneous media, the derived nonlinear partial differential…

Analysis of PDEs · Mathematics 2015-11-02 Emine Celik , Luan Hoang