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Late time cosmic acceleration may be achieved by modifying gravity on large scales. This should also have consequences on the evolution of perturbations. We thus extend our study of exponential infrared $f(T)$ teleparallel gravity to…

Cosmology and Nongalactic Astrophysics · Physics 2023-01-11 Mahmoud Hashim , Amr A. El-Zant , Waleed El Hanafy , Alexey Golovnev

Combining Supernovae, Baryon Acoustic Oscillations and Redshift-Space Distortions data from the next generation of (Stage-IV) cosmological surveys, we aim to reconstruct the expansion history up to large redshifts using forward-modeling of…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-29 R. Calderón , B. L'Huillier , D. Polarski , A. Shafieloo , A. A. Starobinsky

Motivated by the fact that any nonzero $\Lambda$ can introduce a length scale or a time scale into Einstein's theory, $r_{\Lambda}=ct_{\Lambda}=\sqrt{3/|\Lambda|}$. Conversely, any cosmological length scale or time scale can introduce a…

Cosmology and Nongalactic Astrophysics · Physics 2011-04-04 Yun Chen , Zong-Hong Zhu , Lixin Xu , J. S. Alcaniz

This study investigates the cosmological dynamics of an accelerating universe within the framework of teleparallel gravity using an exponential f(T) functional form. To obtain exact cosmological solutions, a hybrid scale factor is employed…

General Relativity and Quantum Cosmology · Physics 2026-05-27 Rajalakshmi Jena , Vishal M C , Sankarsan Tarai

The concordance (LambdaCDM) model reproduces the main current cosmological observations assuming the validity of general relativity at all scales and epochs, the presence of cold dark matter, and of a cosmological constant, equivalent to a…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-08 Guido Risaliti , Elisabeta Lusso

Nonparametric mean function regression with repeated measurements serves as a cornerstone for many statistical branches, such as longitudinal/panel/functional data analysis. In this work, we investigate this problem using fully connected…

Statistics Theory · Mathematics 2025-02-27 Shunxing Yan , Fang Yao , Hang Zhou

The $\Lambda$CDM model successfully explains a wide range of cosmological observations; however, persistent discrepancies most notably the $H_0$ tension between early and late time measurements challenge its completeness. No proposed…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-31 Upala Mukhopadhyay , Purba Mukherjee , Alexandre Tkatchenko

A natural extension of the standard cosmological model are models that include curvature as a free parameter. In this work we study in detail the observational constraints on the non-flat $\Lambda CDM$ model using the two main geometric…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-15 Velasquez-Toribio , A. M , Magnago , A. dos R

We perform a comprehensive observational test of a canonical quintessence model driven by an exponential potential, motivated by its emergence in higher-dimensional theories, string-inspired scenarios, and modified gravity. Using a Markov…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-07 Sanjeeda Sultana , Surajit Chattopadhyay

Recent cosmological observations show hints for possible deviations from the standard $\Lambda$CDM paradigm at late times. To study such deviation, we introduce a minimal phenomenological framework in which the total equation of state of…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-18 Shibendu Gupta Choudhury , Anjan A Sen

In the current work, we have implemented an extension of the standard Gaussian Process formalism, namely the Multi-Task Gaussian Process with the ability to perform a joint learning of several cosmological data simultaneously. We have…

Cosmology and Nongalactic Astrophysics · Physics 2018-10-15 Balakrishna S. Haridasu , Vladimir V. Luković , Michele Moresco , Nicola Vittorio

In this paper, linear first order expansion of deceleration parameter $q(z)=q_0+q_1(1-a)$ ($M_1$), constant jerk $j=j_0$ ($M_2$) and third order expansion of luminosity distance ($M_3$) are confronted with cosmic observations: SCP 307 SN…

Cosmology and Nongalactic Astrophysics · Physics 2009-07-24 Lixin Xu , Wenbo Li , Jianbo Lu

We review the observational foundations of the $\Lambda$CDM model, considered by most cosmologists as the standard model of cosmology. The Cosmological Principle, a key assumption of the model is shown to be verified with increasing…

Cosmology and Nongalactic Astrophysics · Physics 2013-04-17 Jean-Christophe Hamilton

The paradigm of \Lambda CDM cosmology works impressively well and with the concept of inflation it explains the universe after the time of decoupling. However there are still a few concerns; after much effort there is no detection of dark…

General Physics · Physics 2017-03-22 B. Vlahovic

We investigate the null tests of cosmic accelerated expansion by using the Baryon Acoustic Oscillation (BAO) data measured by the Dark Energy Spectroscopic Instrument (DESI) and reconstruct the dimensionless Hubble parameter $E(z)$ from the…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-23 Xuchen Lu , Shengqing Gao , Yungui Gong

Recently, in [1], we presented the first combined non-parametric reconstruction of the three time-dependent functions that capture departures from the standard cosmological model, $\Lambda$CDM, in the expansion history and gravitational…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-08 Marco Raveri , Levon Pogosian , Matteo Martinelli , Kazuya Koyama , Alessandra Silvestri , Gong-Bo Zhao

This paper examines the late-time accelerating Universe and the formation of large-scale structures within the modified symmetric teleparallel gravity framework, specifically using the $f(Q)$-gravity model, in light of recent cosmological…

General Relativity and Quantum Cosmology · Physics 2024-12-31 Shambel Sahlu , Amare Abebe

We study the accelerated expansion phase of the universe by using the {\textit{kinematic approach}}. In particular, the deceleration parameter $q$ is parametrized in a model-independent way. Considering a generalized parametrization for…

General Relativity and Quantum Cosmology · Physics 2018-10-22 Abdulla Al Mamon , Kazuharu Bamba

The field of machine learning has drawn increasing interest from various other fields due to the success of its methods at solving a plethora of different problems. An application of these has been to train artificial neural networks to…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-21 Augusto T. Chantada , Susana J. Landau , Pavlos Protopapas , Claudia G. Scóccola , Cecilia Garraffo

Through likelihood analyses of both current and future data that constrain both the expansion history of the universe and the clustering of matter fluctuations, we provide falsifiable predictions for three broad classes of models that…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-18 V Miranda , Cora Dvorkin
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