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Using the cosmological date sets, the cosmological parameters are constrained in this paper, with some well known form of Hubble parameter. To understand the dynamics of the Weyl type $f(Q,T)$, functional form $f(Q,T)$ has been introduced,…

General Relativity and Quantum Cosmology · Physics 2024-09-05 Rahul Bhagat , B. Mishra

Cosmological probes pose an inverse problem where the measurement result is obtained through observations, and the objective is to infer values of model parameters which characterize the underlying physical system -- our Universe. Modern…

Instrumentation and Methods for Astrophysics · Physics 2019-05-21 Timur Takhtaganov , Zarija Lukic , Juliane Mueller , Dmitriy Morozov

Machine learning (ML) methods have become popular for parameter inference in cosmology, although their reliance on specific training data can cause difficulties when applied across different data sets. By reproducing and testing networks…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-23 Kimeel Sooknunan , Emma Chapman , Luke Conaboy , Daniel Mortlock , Jonathan Pritchard

The unknown physical nature of the Dark Energy motivates in cosmology the study of modifications of the gravity theory at large distances. One of these types of modifications is to consider gravity theories, generally termed as $f(R)$. In…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-07 Pedro Bessa , Marcela Campista , Armando Bernui

Next-generation cosmic microwave background (CMB) experiments will have lower noise and therefore increased sensitivity, enabling improved constraints on fundamental physics parameters such as the sum of neutrino masses and the…

Cosmology and Nongalactic Astrophysics · Physics 2020-06-16 João Caldeira , W. L. Kimmy Wu , Brian Nord , Camille Avestruz , Shubhendu Trivedi , Kyle T. Story

Investigating the accelerated expansion of the universe with cosmography is a best method to constraint cosmological models. In this work, in the $F(G)$ modified gravity framework, we obtain equations of motion in a flat FRW metric. Then we…

General Physics · Physics 2012-06-04 M. R. Setare , N. Mohammadipour

In this study, we present a novel approach to mimetic gravity incorporating a non-zero nonmetricity tensor with vanishing torsion and curvature, establishing a generalized mimetic-$f(Q)$ gravity framework. Using the Lagrange multiplier…

General Relativity and Quantum Cosmology · Physics 2024-09-20 Adam Z. Kaczmarek

Recent astronomical observations indicate that the Universe is presently almost flat and undergoing a period of accelerated expansion. Basing on Einstein's general relativity all these observations can be explained by the hypothesis of a…

Astrophysics · Physics 2007-06-13 Marek Szydlowski , Aleksandra Kurek , Adam Krawiec

In this paper we introduce a new public Einstein-Boltzmann solver, \texttt{MGCLASS II}, built as a modification to the publicly available \texttt{CLASS} code, that allows to obtain cosmological observables for Modified Gravity theories. It…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-28 Ziad Sakr , Matteo Martinelli

While the use of numerical general relativity for modeling astrophysical phenomena and compact objects is commonplace, the application to cosmological scenarios is only just beginning. Here, we examine the expansion of a spacetime using the…

General Relativity and Quantum Cosmology · Physics 2016-06-27 John T. Giblin , James B. Mertens , Glenn D. Starkman

In this paper, we focus on the parametrization of the effective equation of state (EoS) parameter within the framework of $f(Q)$ symmetric teleparallel gravity. Here, the gravitational action is represented by an arbitrary function of the…

General Relativity and Quantum Cosmology · Physics 2023-07-04 A. Mussatayeva , N. Myrzakulov , M. Koussour

Modified gravity (MG) theories predict, in general, that the ratio of gravitational wave (GW) to electromagnetic (EM) luminosity distances, $\Xi$, differs from its general relativity (GR) value of unity at cosmological scales, thus…

General Relativity and Quantum Cosmology · Physics 2021-05-28 Isabela S. Matos , Maurício O. Calvão , Ioav Waga

Likelihood-free inference provides a rigorous approach to preform Bayesian analysis using forward simulations only. The main advantage of likelihood-free methods is its ability to account for complex physical processes and observational…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-09 Sut-Ieng Tam , Keiichi Umetsu , Adam Amara

Recent measurements of type Ia supernovae as well as other concordant observations suggest that the expansion of our universe is accelerating. A dark energy component has usually been invoked as the most feasible mechanism for the…

Astrophysics · Physics 2014-10-13 Zong-Hong Zhu , Masa-Katsu Fujimoto , Xiang-Tao He

We investigate cosmological constraints on K-mouflage models of modified gravity. We consider two scenarios: one where the background evolution is free to deviate from $\Lambda$CDM (K-mouflage) and another one which reproduces a…

Cosmology and Nongalactic Astrophysics · Physics 2019-05-29 Giampaolo Benevento , Marco Raveri , Andrei Lazanu , Nicola Bartolo , Michele Liguori , Philippe Brax , Patrick Valageas

We propose a novel model in the framework of $f(Q)$ gravity, which is a gravitational modification class arising from the incorporation of non-metricity. The model has General Relativity as a particular limit, it has the same number of free…

General Relativity and Quantum Cosmology · Physics 2021-09-15 Fotios K. Anagnostopoulos , Spyros Basilakos , Emmanuel N. Saridakis

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

An observational program focused on the high redshift ($2<z<6$) Universe has the opportunity to dramatically improve over upcoming LSS and CMB surveys on measurements of both the standard cosmological model and its extensions. Using a…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-04 Noah Sailer , Emanuele Castorina , Simone Ferraro , Martin White

While Hamiltonian mechanics provides a powerful inductive bias for neural networks modeling dynamical systems, Hamiltonian Neural Networks and their variants often fail to capture complex temporal dynamics spanning multiple timescales. This…

Machine Learning · Computer Science 2026-03-17 Yaojun Li , Yulong Yang , Christine Allen-Blanchette

Convolutional Neural Networks (CNN) have recently been demonstrated on synthetic data to improve upon the precision of cosmological inference. In particular they have the potential to yield more precise cosmological constraints from weak…

Cosmology and Nongalactic Astrophysics · Physics 2019-09-17 Janis Fluri , Tomasz Kacprzak , Aurelien Lucchi , Alexandre Refregier , Adam Amara , Thomas Hofmann , Aurel Schneider
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