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We present cosmo_learn, an open-source python-based software package designed to simulate cosmological data and perform data-driven inference using a range of modern statistical and machine learning techniques. Motivated by the growing…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-29 Reginald Christian Bernardo , Daniela Grandón , Jackson Levi Said , Víctor H. Cárdenas , Gene Carlo Belinario , Reinabelle Reyes

In this paper we obtain some cosmological solutions that describe the present period of accelerating expansion of the universe in the framework of a geometrical gauge scalar-tensor theory of gravity. The background geometry in the model is…

General Relativity and Quantum Cosmology · Physics 2023-03-08 José Edgar Madriz Aguilar , M. Montes , A. Bernal

Aims. We investigated the gravitational effects of a scalar field within scalar-tensor gravity as an alternative to dark matter. Motivated by chameleon, symmetron and f(R)-gravity models, we studied a phenomenological scenario where the…

Cosmology and Nongalactic Astrophysics · Physics 2014-01-24 David F. Mota , Vincenzo Salzano , Salvatore Capozziello , Nicola R. Napolitano

The dark energy plus cold dark matter ($\Lambda$CDM) cosmological model has been a demonstrably successful framework for predicting and explaining the large-scale structure of Universe and its evolution with time. Yet on length scales…

Cosmology and Nongalactic Astrophysics · Physics 2019-09-04 James S. Bullock , Michael Boylan-Kolchin

In this work we present a model of dark matter based on scalar-tensor theory of gravity. With this scalar field dark matter model we study the non-linear evolution of the large scale structures in the universe. The equations that govern the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Mario A. Rodriguez-Meza

It has been argued that the small perturbations to the homogeneous and isotropic configurations of a canonical scalar field in an expanding universe do not grow. We show that this is not true in general, and clarify the root of the…

General Relativity and Quantum Cosmology · Physics 2015-09-23 Miguel Alcubierre , Axel de la Macorra , Alberto Diez-Tejedor , José M. Torres

We investigate the Universe evolution at late-time stages in models of teleparallel gravity with power-law nonminimal coupling and a decreasing power-law potential of the scalar field $\phi$. New asymptotic solutions are found analytically…

General Relativity and Quantum Cosmology · Physics 2018-05-08 Maria A. Skugoreva

Scalar dark matter is a viable alternative to particle dark matter models such as Weakly Interacting Massive Particles (WIMPS). This is particularly the case for scalars with a low mass $m \gtrsim 10^{-21} {\rm eV}$ as required to make…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-07 Philippe Brax , Patrick Valageas

An algorithm is used to generate new solutions of the scalar field equations in homogeneous and isotropic universes. Solutions can be found for pure scalar fields with various potentials in the absence and presence of spatial curvature and…

General Relativity and Quantum Cosmology · Physics 2016-11-23 John D. Barrow , Andronikos Paliathanasis

Gammapy is a Python package for high-level gamma-ray data analysis built on Numpy, Scipy and Astropy. It enables us to analyze gamma-ray data and to create sky images, spectra and lightcurves, from event lists and instrument response…

Friedmans cosmological equations for the scale factor are analyzed for the Universe containing dark energy. The parameter of the equation of state of the dark energy is treated as an arbitrary constant whose value lies within the interval…

Cosmology and Nongalactic Astrophysics · Physics 2011-09-13 M. V. Sazhin , O. S. Sazhina , U. Chadayammuri

In this work, we analyse the late-time evolution of the universe for a particular $f(R)$ gravity model built from an exponential function of the scalar curvature. Following the literature, we write the field equations in terms of a suited…

General Relativity and Quantum Cosmology · Physics 2023-10-18 A. Oliveros , Mario A. Acero

This article discusses a dark energy cosmological model in the standard theory of gravity - general relativity with a broad scalar field as a source. Exact solutions of Einstein's field equations are derived by considering a particular form…

General Relativity and Quantum Cosmology · Physics 2022-08-23 S. K. J. Pacif , Simran Arora , P. K. Sahoo

In this paper we review in detail a number of approaches that have been adopted to try and explain the remarkable observation of our accelerating Universe. In particular we discuss the arguments for and recent progress made towards…

High Energy Physics - Theory · Physics 2008-11-26 Edmund J. Copeland , M. Sami , Shinji Tsujikawa

We present the description of the project \texttt{SCORPIO}, a Python package for retrieving images and associated data of galaxy pairs based on their position, facilitating visual analysis and data collation of multiple archetypal systems.…

Instrumentation and Methods for Astrophysics · Physics 2021-11-09 Jose A. Benavides , Martín Chalela , Juan B. Cabral , Bruno O. Sánchez , Sebastian Gurovich

Large-scale structure surveys measure the shapes and positions of millions of galaxies in order to constrain the cosmological model with high precision. The resulting large data volume poses a challenge for the analysis of the data, from…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-28 Silvan Fischbacher , Beatrice Moser , Tomasz Kacprzak , Joerg Herbel , Luca Tortorelli , Uwe Schmitt , Alexandre Refregier , Adam Amara

The main aim of this paper is to analyse minimally-coupled scalar-fields -- quintessence and phantom -- as the main candidates to explain the accelerated expansion of the universe and compare its observables to current cosmological…

General Relativity and Quantum Cosmology · Physics 2021-02-10 J. Alberto Vázquez , David Tamayo , Anjan A. Sen , Israel Quiros

Several extensions of General Relativity and high energy physics include scalar fields as extra degrees of freedom. In the search for predictions in the non-linear regime of cosmological evolution, the community makes use of numerical…

Cosmology and Nongalactic Astrophysics · Physics 2014-09-04 Claudio Llinares , David Mota

We introduce a new logotropic model based on a complex scalar field with a logarithmic potential that unifies dark matter and dark energy. The scalar field satisfies a nonlinear wave equation generalizing the Klein-Gordon equation in the…

General Relativity and Quantum Cosmology · Physics 2022-10-05 Pierre-Henri Chavanis

We investigated the evolution of the background expansion and the growth rate of the matter density fluctuations in the scalar field $\phi$CDM Ratra-Peebles model. We constrained the model parameter $\alpha$ and the matter density parameter…

Cosmology and Nongalactic Astrophysics · Physics 2019-09-04 Olga Avsajanishvili
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