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The inherent uncertainty of communication channels implies that any coding scheme has a non-zero probability of failing to correct errors, making retransmission mechanisms essential. To ensure message reliability and integrity, a dual-layer…

Information Theory · Computer Science 2025-11-20 Chaofeng Guan , Gaojun Luo , Lan Luo , Yangyang Fei , Hong Wang

We continue our investigation of the configuration space of general relativity begun in I (gr-qc/9411009). Here we examine the Hamiltonian constraint when the spatial geometry is momentarily static (MS). We show that MS configurations…

General Relativity and Quantum Cosmology · Physics 2009-10-22 Jemal Guven , Niall Ó Murchadha

Generic object counting in natural scenes is a challenging computer vision problem. Existing approaches either rely on instance-level supervision or absolute count information to train a generic object counter. We introduce a partially…

Computer Vision and Pattern Recognition · Computer Science 2020-09-04 Hisham Cholakkal , Guolei Sun , Salman Khan , Fahad Shahbaz Khan , Ling Shao , Luc Van Gool

We describe the construction of an N-body simulation that mimics the true velocity and mass-density fields in a box of side 256\hmpc about the Local Group , and the production of mock catalogs that mimic in detail current catalogs of…

Astrophysics · Physics 2009-10-28 Tsafrir Kolatt , Avishai Dekel , Galit Ganon , Jeffrey Willick

The bispectrum of galaxy number counts is a key probe of large-scale structure, offering insights into the initial conditions of the Universe, the nature of gravity, and cosmological parameters. In this work, we present the first full-sky…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-22 Thomas Montandon , Enea Di Dio , Cornelius Rampf , Julian Adamek

First-order variational equations are widely used in N-body simulations to study how nearby trajectories diverge from one another. These allow for efficient and reliable determinations of chaos indicators such as the Maximal Lyapunov…

Earth and Planetary Astrophysics · Physics 2016-03-23 Hanno Rein , Daniel Tamayo

We present a new N-body code, gevolution, for the evolution of large scale structure in the Universe. Our code is based on a weak field expansion of General Relativity and calculates all six metric degrees of freedom in Poisson gauge.…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-05 Julian Adamek , David Daverio , Ruth Durrer , Martin Kunz

We compare two competing relativistic approaches to the N-body simulation of the Universe large-scale structure. To this end, employing the corresponding alternative computer codes ("gevolution" and "screening"), we conduct a series of…

General Relativity and Quantum Cosmology · Physics 2022-02-09 Maxim Eingorn , A. Emrah Yukselci , Alexander Zhuk

We present an updated analysis of the first-order phase transition associated with symmetry breaking in the early Universe in a classically scale-invariant model extended with a new SU(2) gauge group. Including recent developments in…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-03 Maciej Kierkla , Alexandros Karam , Bogumila Swiezewska

Analytical computations in relativistic cosmology can be split into two sets: time evolution relating the initial conditions to the observer's light-cone and light propagation to obtain observables. Cosmological perturbation theory in the…

General Relativity and Quantum Cosmology · Physics 2021-01-18 Ermis Mitsou , Giuseppe Fanizza , Nastassia Grimm , Jaiyul Yoo

The Refinement Calculus of Reactive Systems (RCRS) is a compositional formal framework for modeling and reasoning about reactive systems. RCRS provides a language which allows to describe atomic components as symbolic transition systems or…

Logic in Computer Science · Computer Science 2018-02-09 Viorel Preoteasa , Iulia Dragomir , Stavros Tripakis

Accounting for all the relativistic effects, we have developed the fully nonlinear gauge-invariant formalism for describing the cosmological observables and presented the second-order perturbative expressions associated with light…

Cosmology and Nongalactic Astrophysics · Physics 2022-10-03 Matteo Magi , Jaiyul Yoo

We investigate the imprints of the Generalized Uncertainty Principle on cosmological scales by using redshift-space distortion measurements in combination with background cosmological data to determine constraints on the deformation…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-03 Andronikos Paliathanasis

Two-parameter perturbation theory (2PPT) is a framework designed to include the relativistic gravitational effects of small-scale nonlinear structures on the large-scale properties of the Universe. In this paper we use the 2PPT framework to…

General Relativity and Quantum Cosmology · Physics 2021-09-01 Christopher S. Gallagher , Timothy Clifton , Chris Clarkson

We present general relativistic correction terms appearing in Newton's gravity to the second-order perturbations of cosmological fluids. In our previous work we have shown that to the second-order perturbations, the density and velocity…

Astrophysics · Physics 2008-12-18 J. Hwang , H. Noh

In this paper we present four simple expressions for the relativistic first and second order fractional density perturbations for $\Lambda$CDM cosmologies in different gauges: the Poisson, uniform curvature, total matter and synchronous…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Claes Uggla , John Wainwright

We investigate the generation of gravitational waves due to the gravitational instability of primordial density perturbations in an early matter-dominated era which could be detectable by experiments such as LIGO and LISA. We use…

Cosmology and Nongalactic Astrophysics · Physics 2010-01-15 Hooshyar Assadullahi , David Wands

The abundance and distribution of collapsed objects such as galaxy clusters will become an important tool to investigate the nature of dark energy and dark matter. Number counts of very massive objects are sensitive not only to the equation…

Astrophysics · Physics 2010-05-12 L. R. Abramo , R. C. Batista , L. Liberato , R. Rosenfeld

We present a first-principles-based (second-principles) scheme that permits large-scale materials simulations including both atomic and electronic degrees of freedom on the same footing. The method is based on a predictive…

Materials Science · Physics 2016-06-08 Pablo García-Fernández , Jacek C. Wojdeł , Jorge Íñiguez , Javier Junquera

Finite dimensional models that mimic the constraint structure of Einstein's General Relativity are quantized in the framework of BRST and Dirac's canonical formalisms. The first system to be studied is one featuring a constraint quadratic…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Daniel M. Sforza
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