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Related papers: Constraining Palatini cosmological models using GR…

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We extend the Hubble diagram up to $z = 5.6$ using 63 gamma-ray bursts (GRBs) via peak energy-peak luminosity relation (so called Yonetoku relation), and obtain constraints on cosmological parameters including dynamical dark energy…

In the case of Gamma-Ray Bursts with measured redshift, we can calculate the k-correction to get the fluence and energy that were actually produced in the comoving system of the GRB. To achieve this we have to use well-fitted parameters of…

High Energy Astrophysical Phenomena · Physics 2012-04-06 Andras Kovacs , Zsolt Bagoly , Lajos G. Balazs , Istvan Horvath , Peter Veres

We consider two empirical relations using data only from the prompt emission of Gamma-Ray Bursts (GRBs), peak energy ($E_p$) - peak luminosity ($L_p$) relation (so called Yonetoku relation) and $E_p$-isotropic energy ($E_{\rm iso}$)…

The evidence of the acceleration of universe at present time has lead to investigate modified theories of gravity and alternative theories of gravity, which are able to explain acceleration from a theoretical viewpoint without the need of…

High Energy Physics - Theory · Physics 2011-05-05 Gianluca Allemandi , Andrzej Borowiec , Mauro Francaviglia

Searching for Lorentz invariance violation (LIV) using astrophysical sources such as gamma-ray bursts (GRBs) is crucial for probing quantum gravity. However, the dependence of LIV constraints on assumed cosmological models has been largely…

High Energy Astrophysical Phenomena · Physics 2025-12-01 Jun Tian , Yu Pan , Shuo Cao , Qing-Quan Jiang , Wei-Liang Qian

In this manuscript I review the mathematics and physics that underpins recent work using the clustering of galaxies to derive cosmological model constraints. I start by describing the basic concepts, and gradually move on to some of the…

Astrophysics · Physics 2009-07-28 Will J. Percival

We discuss the prospects of using Gamma Ray Bursts (GRBs) as high-redshift distance estimators, and consider their use in the study of two dark energy models, the Generalized Chaplygin Gas (GCG), a model for the unification of dark energy…

Astrophysics · Physics 2007-05-23 O. Bertolami , P. T. Silva

The observed accelerated expansion of the Universe at present epoch can be explained by some of the $f(R)$ models without invoking the existence of dark energy or any other such exotic component in cosmic fluid. The $f(R)$ models in…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-09 Kumar Ravi

We search for possible time lags caused by quantum gravitational (QG) effects using gamma-ray bursts (GRBs) detected by INTEGRAL. The advantage of this satellite is that we have at our disposal the energy and arrival time of every detected…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Raphael Lamon , Nicolas Produit , Frank Steiner

Cosmology in extended theories of gravity is considered assuming the Palatini variational principle, for which the metric and connection are independent variables. The field equations are derived to linear order in perturbations about the…

Astrophysics · Physics 2015-06-24 Tomi Koivisto , Hannu Kurki-Suonio

We use lookback time versus redshift data from galaxy clusters (Capozziello et al., 2004) and passively evolving galaxies (Simon et al., 2005), and apply a bayesian prior on the total age of the Universe based on WMAP measurements, to…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Lado Samushia , Abha Dev , Deepak Jain , Bharat Ratra

In this paper, we obtain two improved Amati correlations of the Gamma-Ray burst (GRB) data via a powerful statistical tool called copula. After calibrating, with the low-redshift GRB data, the improved Amati correlations based on a fiducial…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-01 Yang Liu , Fuyong Chen , Nan Liang , Zunli Yuan , Hongwei Yu , Puxun Wu

The properties of the cosmic Gamma-ray Bursts (GRBs) are briefly summarized. A detailed bibliography is given with titles of the papers. Two fundamental theoretical problems are pointed out: the problem of the energy source, and the problem…

Astrophysics · Physics 2015-06-24 S. Blinnikov

We investigate cosmological consequences of a class of exponential $f(R)$ gravity in the Palatini formalism. By using the current largest type Ia Supernova sample along with determinations of the cosmic expansion at intermediary and…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 M. Campista , B. Santos , J. Santos , J. S. Alcaniz

We use a new method of analysis to determine parameters of cosmological gamma-ray bursts (GRBs), assuming that their distribution follows the star-formation history of the universe. Spectral evolution is calculated from an external shock…

Astrophysics · Physics 2015-06-24 M. Boettcher , C. D. Dermer

We constrain the parameters describing the kinematical state of the universe using a cosmographic approach, which is fundamental in that it requires a very minimal set of assumptions (namely to specify a metric) and does not rely on the…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Vincenzo Vitagliano , Jun-Qing Xia , Stefano Liberati , Matteo Viel

We discuss several constraints on the properties of gamma-ray bursts (GRB) at cosmological distances. First we use the requirement that burst sources must be optically thin to pair production by photon-photon collisions in order to produce…

Astrophysics · Physics 2009-10-28 Eric Woods , Abraham Loeb

Fourth - order gravity theories have received much interest in recent years thanks to their ability to provide an accelerated cosmic expansion in a matter only universe. In these theories, the Lagrangian density of the gravitational field…

Cosmology and Nongalactic Astrophysics · Physics 2009-07-28 Vincenzo F. Cardone , Antonaldo Diaferio , Stefano Camera

We present the results of the optical, X-ray and gamma-ray analysis of some recent GRBs. The data were obtained by the automated P60 telescope and the Swift telescope (UVOT, XRT and BAT). We present some example fits for the lightcurves.…

High Energy Astrophysical Phenomena · Physics 2011-12-08 József Kóbori , János Kelemen , Péter Veres , S. Bradley Cenko , Derek Fox

In this paper, we test the consistency of Gamma Ray Bursts (GRBs) Data-set and Supernovae Union2 (SNU2) via the so-called {\it multi-dimensional consistency test} under the assumption that $\Lambda$CDM model is a potentially correct…

Cosmology and Nongalactic Astrophysics · Physics 2010-11-19 Lixin Xu , Yuting Wang
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