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Related papers: Cosmic crystallography: the euclidean isometries

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Isotropic cosmological singularities are singularities which can be removed by rescaling the metric. In some cases already studied (gr-qc/9903008, gr-qc/9903009, gr-qc/9903018) existence and uniqueness of cosmological models with data at…

General Relativity and Quantum Cosmology · Physics 2017-08-23 K. P. Tod

The complexity and accuracy of current and future precision cosmology observational campaigns has made it essential to develop an efficient technique for directly combining simulation and observational datasets to determine cosmological and…

Astrophysics · Physics 2009-11-11 Katrin Heitmann , David Higdon , Charles Nakhleh , Salman Habib

The pair separations statistical methods devised to detect the topology of the universe rely on the accurate knowledge of the three-dimensional positions of the cosmic sources. The determination of these positions, however, involves…

Astrophysics · Physics 2016-11-09 A. Bernui , G. I. Gomero , B. Mota , M. J. Reboucas

Regular model sets, describing the point positions of ideal quasicrystallographic tilings, are mathematical models of quasicrystals. An important result in mathematical diffraction theory of regular model sets, which are defined on locally…

Mathematical Physics · Physics 2008-08-28 Christoph Richard

A dynamical correspondence is established between positively curved, isotropic, perfect fluid cosmologies and quasi-two-dimensional, harmonically trapped Bose-Einstein condensates by mapping the equations of motion for both systems onto the…

General Relativity and Quantum Cosmology · Physics 2009-11-10 James E. Lidsey

Density profiles of cosmological virialized systems, or dark halos, have recently attracted much attention. I first present a brief historical review of numerical simulations to quantify the halo density profiles. Then I describe the latest…

Astrophysics · Physics 2007-05-23 Yasushi Suto

Galactic accretion interacts in complex ways with gaseous halos, including galactic winds. As a result, observational diagnostics typically probe a range of intertwined physical phenomena. Because of this complexity, cosmological…

Astrophysics of Galaxies · Physics 2017-05-31 C. -A. Faucher-Giguere

We investigate one-dimensional periodic chains of alternate type of particles interacting through mirror symmetric potentials. The optimality of the equidistant configuration at fixed density -- also called crystallization -- is shown in…

Optimization and Control · Mathematics 2020-07-13 Laurent Bétermin , Hans Knüpfer , Florian Nolte

Scaling relations of galaxy clusters are a powerful probe of cosmic isotropy in the late Universe. Owing to their strong cosmological dependence, galaxy cluster scaling relations can obtain tight constraints on the spatial variation of…

Cosmology and Nongalactic Astrophysics · Physics 2024-06-05 Konstantinos Migkas

We investigate to what extent the cosmic crystallographic methods aimed to detect the topology of the universe using catalogues of cosmic objects would be damaged by various observational uncertainties. We find that the topological…

Astrophysics · Physics 2011-05-23 Roland Lehoucq , Jean-Philippe Uzan , Jean-Pierre Luminet

Clusters of galaxies can be used for very different kinds of cosmological tests. I review a few of the methods: determination of cluster masses and dark matter content, metal enrichment and its connection to the origin of the intra-cluster…

Astrophysics · Physics 2007-05-23 Sabine Schindler

The two fundamental assumptions in cosmology are that the Universe is statistically homogeneous and isotropic when averaged on large scales. Given the big implication of these assumptions, there has been a lot of statistical tests carried…

Cosmology and Nongalactic Astrophysics · Physics 2014-09-04 Yabebal Fantaye

Cosmography is the tool that makes possible to untie the interpretation of cosmological observations from the definition of any dynamical prior. We review the constraints on the cosmographic parameter obtained using the most thorough data…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-01 Vincenzo Vitagliano , Jun-Qing Xia , Stefano Liberati , Matteo Viel

Multi-connected universe models with space identification scales smaller than the size of the observable universe produce topological images of cosmic sources. We generalise to locally hyperbolic spaces the crystallographic method, aimed to…

Astrophysics · Physics 2011-05-23 Jean-Philippe Uzan , Roland Lehoucq , Jean-Pierre Luminet

We try to apply the cosmic crystallography method of Lehoucq, Lachieze-Rey, and Luminet to a universe model with closed spatial section of negative curvature. But the sharp peaks predicted for Einstein-de Sitter closed models do not appear…

Astrophysics · Physics 2016-08-15 H. V. Fagundes , E. Gausmann

Efficient heuristics have predicted many functional materials such as high-temperature superconducting hydrides, while inorganic structural chemistry explains why and how the crystal structures are stabilized. Here we develop the paired…

Materials Science · Physics 2024-11-07 Ryotaro Koshoji , Taisuke Ozaki

An isometry is a geometric transformation that preserves distances between pairs of points. We present methods to classify isometries in the Euclidean plane, and extend these methods to spherical, single elliptical, and hyperbolic geometry.…

Metric Geometry · Mathematics 2023-06-28 Lillian MacArthur , Honglin Zhu

Isomerization, i.e. the rearrangement between distinct molecular configurations, is a fundamental process in chemistry. Here we demonstrate that two-dimensional Coulomb crystals can emulate molecular isomerization and be used to…

Atomic Physics · Physics 2025-08-11 Naoto Mizukami , Gabriele Gatta , Lucia Duca , Carlo Sias

The isothermal compression of a dilute nucleonic gas invoking cluster degrees of freedom is studied in an equilibrium statistical model; this clusterized system is found to be more stable than the pure nucleonic system. The equation of…

Nuclear Theory · Physics 2008-11-26 J. N. De , S. K. Samaddar

In addition to cosmological tests based on the mass function and clustering of galaxy clusters, which probe the growth of cosmic structure, nature offers two independent ways of using clusters to measure cosmic distances. The first uses…

Cosmology and Nongalactic Astrophysics · Physics 2013-08-01 S. W. Allen , A. B. Mantz , R. G. Morris , D. E. Applegate , P. L. Kelly , A. von der Linden , D. A. Rapetti , R. W. Schmidt