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Related papers: A cosmological model in Weyl-Cartan spacetime: II.…

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In this work we study the magnitude-redshift relation of a non-standard cosmological model. The model under consideration was firstly investigated within a special case of metric-affine gravity (MAG) and was recently recovered via different…

General Relativity and Quantum Cosmology · Physics 2009-04-03 Dirk Puetzfeld , Xuelei Chen

In this first article of a series on alternative cosmological models we present an extended version of a cosmological model in Weyl-Cartan spacetime. The new model can be viewed as a generalization of a model developed earlier jointly with…

General Relativity and Quantum Cosmology · Physics 2009-04-03 Dirk Puetzfeld

The luminosity distance - redshift relation for a wide class of generalized Randall-Sundrum type II brane-world models with Weyl fluid is compared to the presently available supernova data. We find that there is a class of spacially flat…

Astrophysics · Physics 2009-09-01 Gyula M. Szabó , László Á. Gergely , Zoltán Keresztes

In this paper, the cosmological parameters are determined by applying six cosmological models to fit the magnitude-redshift relation of the Pantheon Sample consisting of 1048 Type Ia supernovae (SNe Ia) in the range of $0.01 < z < 2.26$.…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-18 Peifeng Peng , Nigel Metcalfe

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

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 investigate some FLRW cosmological models in the context of Metric-Affine $F(R,Q)$ gravity, as proposed in [arXiv:1205.52666]. Here, $R$ and $Q$ are the curvature and nonmetricity scalars using non-special connections, respectively. We…

General Relativity and Quantum Cosmology · Physics 2024-08-16 Dinesh Chandra Maurya , K. Yesmakhanova , R. Myrzakulov , G. Nugmanova

Already the simplest examples of Weyl geometry, the static space-time models of general relativity modified by an additional time-homogeneous Weylian length connection lead to beautiful cosmological models (Weyl universes) . The…

Astrophysics · Physics 2007-05-23 Erhard Scholz

The luminosity distance - redshift relation is analytically given for generalized Randall-Sundrum type II brane-world models containing dark radiation. The derived expressions contain both elementary functions and elliptic integrals of the…

Astrophysics · Physics 2009-09-01 Zoltán Keresztes , László Á. Gergely , Botond Nagy , Gyula M. Szabó

We use cosmography to present constraints on the kinematics of the Universe without postulating any underlying theoretical model a priori. To this end, we use a Markov Chain Monte Carlo analysis to perform comparisons to the supernova Ia…

Cosmology and Nongalactic Astrophysics · Physics 2013-01-18 Alejandro Aviles , Christine Gruber , Orlando Luongo , Hernando Quevedo

This study is devoted to the implications of scale-dependent gravity in Cosmology. Redshift-space distortion data indicate that there is a tension between $\Lambda$CDM and available observations as far as the value of the rms density…

General Relativity and Quantum Cosmology · Physics 2021-06-08 Grigoris Panotopoulos , Ángel Rincón

Based on the magnitude--redshift diagram for the sample of supernovae Ia analysed by Perlmutter et al. (1999), Davis & Lineweaver rule out the special relativistic interpretation of cosmological redshifts at a confidence level of 23 sigma.…

Astrophysics · Physics 2008-11-26 Michal Chodorowski

The cosmological concordance model is consistent with all available observational data, including the apparent distance and redshift relationship for distant supernovae, but it is curious how the Milne cosmological model is able to make…

General Physics · Physics 2007-05-23 Alasdair Macleod

We present a cosmological model for early stages of the universe on the basis of a Weyl-Cartan spacetime. In this model, torsion $T^{\alpha}$ and nonmetricity $Q_{\alpha \beta}$ are proportional to the vacuum polarization. Extending earlier…

General Relativity and Quantum Cosmology · Physics 2009-04-03 Dirk Puetzfeld , Romualdo Tresguerres

In this investigation, we perform an observational statistical analysis in the theory of $ f(R, L_m) $ gravity. The proposed theoretical model is based on the Ricci scalar's non-linear contribution. We use a distinct parameterization for…

General Relativity and Quantum Cosmology · Physics 2024-08-30 J. K. Singh , Shaily , Akanksha Singh , Harshna Balhara , Joao R. L. Santos

We investigate the possibility of testing cosmological models with interaction between matter and energy sector. We assume the standard FRW model while the so called energy conservation condition is interpreted locally in terms of energy…

Astrophysics · Physics 2008-11-26 Marek Szydlowski , Tomasz Stachowiak , Radoslaw Wojtak

In recent years new types of coordinate transformations have appeared in cosmology on top of the standard gauge transformations, such as the dilatations and special conformal transformations, or the ones leading to (conformal) Fermi…

Cosmology and Nongalactic Astrophysics · Physics 2022-10-18 Ermis Mitsou , Jaiyul Yoo

There are two redshifts in cosmology: $z_{obs}$, the observed redshift computed via spectral lines, and the model redshift, $z$, defined by the effective FLRW scale factor. In general these do not coincide. We place observational…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-06 Bruce A. Bassett , Yabebal Fantaye , Renée Hložek , Cristiano Sabiu , Mat Smith

In this paper, we have explored the cosmological implications of Weyl-type $f(Q,T)$ gravity, a modified gravitational theory formulated from Weyl geometry. The nonmetricity scalar $Q$ is coupled to the trace $T$ of the energy-momentum…

General Relativity and Quantum Cosmology · Physics 2025-11-17 Rahul Bhagat , S. K. Tripathy , B. Mishra

Discrepancies between distance measurements and $\Lambda$CDM predictions reveal notable features in the distance-redshift relation, possibly suggesting the presence of an evolving dark energy component. Given the central role of the…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-06 David Camarena , Kylar Greene , John Houghteling , Francis-Yan Cyr-Racine
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