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We present model independent reconstructions of quintessence and the Swampland conjectures (SC) using both Machine Learning (ML) and cosmography. In particular, we demonstrate how the synergies between theoretical analyses and ML can…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-31 Rubén Arjona , Savvas Nesseris

The assumption of a flat Universe that follows the cosmological principle, i.e., that the universe is statistically homogeneous and isotropic at large scales, comprises one of the core foundations of the standard cosmological model --…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-24 Mariana L. S. Dias , Antônio F. B. da Cunha , Carlos A. P. Bengaly , Rodrigo S. Gonçalves , Jonathan Morais

We give distance--redshift relations in terms of elliptic integrals for three different mass distributions of the Friedmann-Lema\^\i tre-Robertson-Walker (FLRW) cosmology. These models are dynamically pressure free FLRW on large scales but,…

Astrophysics · Physics 2007-05-23 R. Kantowski , J. K. Kao , R. C. Thomas

We examine the Pantheon supernovae distance data compilation in a model independent analysis to test the validity of cosmic history reconstructions beyond the concordance $\Lambda$CDM cosmology. Strong deviations are allowed by the data at…

Cosmology and Nongalactic Astrophysics · Physics 2019-03-19 Benjamin L'Huillier , Arman Shafieloo , Eric V. Linder , Alex G. Kim

In this paper we present cosmological constraints on several well-known $f(R)$ models, but also on a new class of models that are variants of the Hu-Sawicki one of the form $f(R)=R-\frac{2\Lambda}{1+b\;y(R,\Lambda)}$, that interpolate…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-29 Judit Pérez-Romero , Savvas Nesseris

In a recent article, Kleidis and Spyrou (2015) proposed that both dark matter (DM) and dark energy (DE) can be treated as a single component, if accommodated in the context of a polytropic DM fluid with thermodynamical content. Depending…

Cosmology and Nongalactic Astrophysics · Physics 2017-10-25 Kostas Kleidis , Nikolaos K. Spyrou

In this work, we revisit/reinterpret/extend the model-independent analysis method (which we now call spread - luminosity distance fitting, spread-LDF) from our previous work. We apply it to the updated supernova type Ia catalogue, Pantheon+…

General Relativity and Quantum Cosmology · Physics 2025-12-02 A. Kazım Çamlıbel , M. Akif Feyizoğlu , İbrahim Semiz

We propose a new and robust method to test the consistency of the cosmic evolution given by a cosmological model. It is realized by comparing the combined quantity r_d^CMB/D_V^SN, which is derived from the comoving sound horizon r_d from…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-30 Yan Gong , Yin-Zhe Ma , Shuang-Nan Zhang , Xuelei Chen

We investigate a spatially flat FLRW cosmological model in the framework of modified gravity described by the function \( f(R, L_m) = \alpha R + L_m^\beta + \gamma \), where \( L_m \) is the matter Lagrangian density. The modified Friedmann…

General Relativity and Quantum Cosmology · Physics 2026-02-05 G. K. Goswami , Anirudh Pradhan , Syamala Krishnannair

Measurements of the $H_0$ and $\sigma_8$ parameters within the standard cosmological model recently highlighted significant statistical tensions between the cosmic microwave background and low-redshift probes, such as local distance ladder,…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-26 Rocco D'Agostino , Rafael C. Nunes

We present a model-independent test of anisotropy in the cosmic distance duality relation (CDDR), $D_L=(1+z)^2 D_A$, using the Pantheon+ type Ia supernova sample and baryon acoustic oscillation (BAO) data. The angular diameter distance is…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-07 Pushty Shrimankar , Gopal Kashyap

The possibility that the $H_0$ tension is a sign of a physics beyond the $\Lambda$CDM model is one of the most exciting possibilities in modern cosmology. The challenge of solving this problem is complicated by several factors, including…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-29 Ramon de Sá , Micol Benetti , Leila Lobato Graef

Our Universe may feature large-scale inhomogeneities and anisotropies which cannot be explained by the standard model of cosmology, that is, the homogeneous and isotropic FLRW metric, on which the $\Lambda$CDM model is built, may not…

Cosmology and Nongalactic Astrophysics · Physics 2022-08-31 V. Marra , T. Castro , D. Camarena , S. Borgani , A. Ragagnin

A cosmographic reconstruction of $f(\mathcal T)$ models is here revised in a model independent way by fixing observational bounds on the most relevant terms of the $f(\mathcal T)$ Taylor expansion. We relate the $f(\mathcal T)$ models and…

General Relativity and Quantum Cosmology · Physics 2015-06-15 Alejandro Aviles , Alessandro Bravetti , Salvatore Capozziello , Orlando Luongo

We consider a varieties of quintessence scalar field models in a homogeneous and isotropic geometry of the universe with zero spatial curvature aiming to provide stringent constraints using a series of cosmological data sets, namely, the…

General Relativity and Quantum Cosmology · Physics 2019-07-24 Weiqiang Yang , M. Shahalam , Barun Pal , Supriya Pan , Anzhong Wang

The standard relation between the cosmological redshift and cosmic scale factor underlies cosmological inference from virtually all kinds of cosmological observations, leading to the emergence of the LambdaCDM cosmological model. This…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-08 Radosław Wojtak , Francisco Prada

We put forward a new model-independent reconstruction scheme for dark energy which utilises the expected geometrical features of the luminosity-distance relation. The important advantage of this scheme is that it does not assume explicit…

Astrophysics · Physics 2008-11-26 Stephane Fay , Reza Tavakol

We constrain and compare the $w_{0}w_{a}$CDM dynamical dark energy model and three $f(R)$ modified gravity models using the current cosmological distance measurements, including 112 high-quality localized FRBs, BAO measurements from the…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-24 Shuai Feng , Yan Gong , Xiaohui Liu , Jun-Hui Yan , Xuelei Chen

This study investigates the potential of a cosmological model termed $\Lambda w$DM, in which a cosmological constant play the role of dark energy and dark matter is barotropic and has a constant equation of state parameter ($w_{\rm dm}$),…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-02 Yan-Hong Yao , Jian-Qi Liu

We proposed a model-independent method to constrain the cosmological parameters using the Distance Sum Rule of the FLRW metric by combining the time delay distances and the comoving distances through a multi-messenger approach. The time…

Cosmology and Nongalactic Astrophysics · Physics 2019-03-06 Yufeng Li , Xilong Fan , Lijun Gou