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Modified gravity theories are a popular alternative to dark energy as a possible explanation for the observed accelerating cosmic expansion, and their cosmological tests are currently an active research field. Studies in recent years have…

Cosmology and Nongalactic Astrophysics · Physics 2016-10-12 Juan J. Ceron-Hurtado , Jian-hua He , Baojiu Li

Nowadays genetic algorithm (GA) is greatly used in engineering pedagogy as an adaptive technique to learn and solve complex problems and issues. It is a meta-heuristic approach that is used to solve hybrid computation challenges. GA…

Other Computer Science · Computer Science 2020-07-27 Tanweer Alam , Shamimul Qamar , Amit Dixit , Mohamed Benaida

We investigate the modified gravity theories in terms of the effective dark energy models. We compare the cosmic expansion history and the linear growth in different models. We also study the evolution of linear cosmological perturbations…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Seokcheon Lee

Building modern deep learning systems that are not just effective but also efficient requires rethinking established paradigms for model training and neural architecture design. Instead of adapting highly overparameterized networks and…

Machine Learning · Computer Science 2025-08-13 Julian Schönberger , Maximilian Zorn , Jonas Nüßlein , Thomas Gabor , Philipp Altmann

A single parameter, the gravitational growth index \gamma, succeeds in characterizing the growth of density perturbations in the linear regime separately from the effects of the cosmic expansion. The parameter is restricted to a very narrow…

Astrophysics · Physics 2010-11-05 Eric V. Linder , Robert N. Cahn

In the pursuit of a general formulation for a modified gravitational theory at the non-relativistic level and as an alternative to the dark matter hypothesis, we construct a model valid over a wide variety of astrophysical scales. Through…

Astrophysics of Galaxies · Physics 2011-12-13 S. Mendoza , X. Hernandez , J. C. Hidalgo , T. Bernal

Recent cosmological tensions, in particular, to infer the local value of the Hubble constant $H_0$, have developed new independent techniques to constrain cosmological parameters in several cosmologies. Moreover, even when the concordance…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-14 Pablo M. Maldonado Alonso , Celia Escamilla-Rivera , Rodrigo Sandoval-Orozco

Allowing the energy of a gravitational field to serve partially as its own source allows gravitating bodies to exhibit stronger fields, as if they were more massive. Depending on degree of compaction of the body, the field could be one to…

Astrophysics · Physics 2013-01-29 Yousef Sobouti

We show that the current accelerated expansion of the Universe can be explained without resorting to dark energy. Models of generalized modified gravity, with inverse powers of the curvature can have late time accelerating attractors…

Astrophysics · Physics 2008-11-26 Olga Mena , Jose Santiago , Jochen Weller

Gaia is a fully-approved all-sky astrometric and photometric survey due for launch in 2011. It will measure accurate parallaxes and proper motions for everything brighter than G=20 (ca. 10^9 stars). Its primary objective is to study the…

Astrophysics · Physics 2007-05-23 Coryn A. L. Bailer-Jones

We review a set of the possible ways to constrain extended gravity models at Galaxy clusters scales (the regime of dark energy explanations and comparison with $\Lambda CDM$), for black hole shadows, gravitational wave astronomy, binary…

General Relativity and Quantum Cosmology · Physics 2022-05-17 Stanislav Alexeyev , Vyacheslav Prokopov

Genetic algorithms have played an important role in engineering optimization. Traditional GAs treat each gene separately. However, biophysical studies of gene regulatory networks revealed direct associations between different genes. It…

Neural and Evolutionary Computing · Computer Science 2024-05-01 Zhaoning Shi , Meng Xiang , Zhaoyang Hai , Xiabi Liu , Yan Pei

The discovery of cosmic acceleration has stimulated theorists to consider dark energy or modifications to Einstein's General Relativity as possible explanations. The last decade has seen advances in theories that go beyond smooth dark…

We combine K-Nearest Neighbors (KNN) with genetic algorithm (GA) for photometric redshift estimation of quasars, short for GeneticKNN, which is a weighted KNN approach supported by GA. This approach has two improvements compared to KNN: one…

Instrumentation and Methods for Astrophysics · Physics 2021-02-10 Bo Han , Li-Na Qiao , Jing-Lin Chen , Xian-Da Zhang , Yanxia Zhang , Yongheng Zhao

In return for the long-standing contributions of Physics to Biology, now the inverse way is frequently traveled through in order to think about many physics phenomena. In this vein, evolutionary algorithms, particularly genetic algorithms,…

Statistical Mechanics · Physics 2007-05-23 Cesar O. Stoico , Danilo G. Renzi , Fernando Vericat

We revisit a model-independent estimator for cosmic acceleration based on type Ia supernovae distance measurements. This approach does not rely on any specific theory for gravity, energy content or parameterization for the scale factor or…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-02 Hermano Velten , Syrios Gomes , Vinicius C. Busti

The paper presents a solution for the problem of choosing a method for analytical determining of weight factors for a genetic algorithm additive fitness function. This algorithm is the basis for an evolutionary process, which forms a stable…

Neural and Evolutionary Computing · Computer Science 2021-03-30 V. K. Ivanov , D. S. Dumina , N. A. Semenov

We examine the dark energy and matter densities allowed by precision measurements of distances out to various redshifts, in the presence of spatial curvature and (near) arbitrary behavior of the dark energy equation of state. Degeneracies…

Cosmology and Nongalactic Astrophysics · Physics 2011-09-22 Arman Shafieloo , Eric V. Linder

The measured cosmic gamma ray background (CGB) spectrum at MeV energies is in reasonable agreement with the predicted contribution from type Ia supernovae (SNIa). But the characteristic features in the SNIa gamma ray spectrum, weakened by…

Astrophysics · Physics 2009-11-10 Pengjie Zhang , John F. Beacom

Despite the ability of the cosmological concordance model ($\Lambda$CDM) to describe the cosmological observations exceedingly well, power law expansion of the Universe scale radius, $R(t)\propto t^n$, has been proposed as an alternative…

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