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We use type Ia supernovae (SN Ia) data in combination with recent baryonic acoustic oscillations (BAO) and cosmic microwave background (CMB) observations to constrain a kink-like parametrization of the deceleration parameter ($q$). This…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-01 R. Giostri , M. Vargas dos Santos , I. Waga , R. R. R. Reis , M. O. Calvão , B. L. Lago

Gamma-ray bursts (GRBs) are cosmological explosions which carry valuable information from the distant past of the expanding universe. One of the greatest discoveries in modern cosmology is the finding of the accelerated expansion of the…

High Energy Astrophysical Phenomena · Physics 2016-06-15 Rupal Basak , A. R. Rao

Several correlations among Gamma Ray Burst (GRB) observables with available redshifts have been recently identified. Proper evaluation and calibration of these correlations may facilitate the use of GRBs as standard candles constraining the…

Astrophysics · Physics 2010-03-19 S. Basilakos , L. Perivolaropoulos

In this work, our focus is on exploring the potential of current GRB measurements to provide reliable constraints on cosmological model parameters at high redshift. This work is divided into two parts. First, we calibrate the Amati relation…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-10 Darshan Kumar , Nisha Rani , Deepak Jain , Shobhit Mahajan , Amitabha Mukherjee

In this paper, we calibrate the luminosity relation of gamma-ray bursts (GRBs) by Artificial Neural Networks (ANN) which is employed to analyze the Pantheon+ sample of type Ia supernovae (SNe Ia) in a manner independent of cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-25 Zhen Huang , Xin Luo , Bin Zhang , Jianchao Feng , Puxun Wu , Yu Liu , Nan Liang

Gamma-ray Bursts can be used as distance indicators using the Combo relation. We show how the proposed THESEUS mission will allow us to investigate the evolution history of the Universe at high redshift with GRBs. Assuming that THESEUS will…

Instrumentation and Methods for Astrophysics · Physics 2018-02-07 L. Izzo , M. Muccino , M. Della Valle

In this paper, we calibrate the luminosity relation of gamma-ray bursts (GRBs) with the machine learning (ML) algorithms from the Pantheon+ sample of type Ia supernovae in a cosmology-independent way. By using K-Nearest Neighbors (KNN) and…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-25 Bin Zhang , Huifeng Wang , Xiaodong Nong , Guangzhen Wang , Puxun Wu , Nan Liang

Three different methods of measuring cosmology with gamma-ray bursts (GRBs) have been proposed since a relation between the $\gamma$-ray energy $E_{\gamma} $ of a GRB jet and the peak energy $E_p$ of the $\nu F_{\nu}$ spectrum in the burst…

Astrophysics · Physics 2009-11-10 D. Xu , Z. G. Dai , E. W. Liang

We combine new Cosmic Microwave Background (CMB) data from Planck with Baryon Acoustic Oscillation (BAO) data to constrain the Brans-Dicke (BD) theory, in which the gravitational constant $G$ evolves with time. Observations of type Ia…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-19 Ji-Xia Li , Feng-Quan Wu , Yi-Chao Li , Yan Gong , Xue-Lei Chen

Standard cosmological models based on general relativity (GR) with dark energy predict that the Universe underwent a transition from decelerating to accelerating expansion at a moderate redshift $z_{acc} \sim 0.7$. Clearly, it is of great…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-05 Will Sutherland , Paul Rothnie

The Sunyaev--Zel'dovich (SZ) effect is a global distortion of the Cosmic Microwave Background (CMB) spectrum as a result of its interaction with a hot electron plasma in the intracluster medium of large structures gravitationally viralized…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-25 Alexander Bonilla , Jairo E. Castillo

The growing tensions between the early Universe and the late Universe increasingly highlight the importance of developing precise probes for late cosmology. As significant late-Universe probes, Type Ia supernovae (SNe Ia) and gravitational…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-09 Jie Zheng , Xiao-Hui Liu , Jing-Zhao Qi

We compare the cosmology of conformal gravity (CG), (Mannheim 2006), to $\Lambda$CDM. CG cosmology has repulsive matter and radiation on cosmological scales, while retaining attractive gravity at local scales. Mannheim (2003) finds that CG…

Cosmology and Nongalactic Astrophysics · Physics 2017-11-29 Carl Roberts , Keith Horne , Alistair O. Hodson , Alasdair Dorkenoo Leggat

There is mounting evidence from multiple cosmological probes that dark energy may be dynamical, with an equation of state that evolves over cosmic time. While this evidence is typically quantified using the Chevallier-Polarski-Linder (CPL)…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-02 Daniel A. Kessler , Luis A. Escamilla , Supriya Pan , Eleonora Di Valentino

It has been suggested that Gamma Ray Bursts (GRB) may enable the expansion rate of our Universe to be measured out to very high redshifts ($z \gsim 5$) just as type Ia supernovae have done at $z \sim$1--1.5. We explore this possibility…

Astrophysics · Physics 2008-11-26 Dan Hooper , Scott Dodelson

Relative distances between a high-redshift sample of Type Ia supernovae (SNe~Ia), anchored to a low-redshift sample, have been instrumental in drawing insights on the nature of the dark energy driving the accelerated expansion of the…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-30 Suhail Dhawan , Brodie Popovic , Ariel Goobar

Gamma-ray bursts (GRBs) are a potential tool to probe high-redshift universe. However, the circularity problem enforces people to find model-independent methods to study the luminosity correlations of GRBs. Here, we present a new method…

High Energy Astrophysical Phenomena · Physics 2019-03-06 Yu-Yang Wang , F. Y. Wang

Gamma-ray bursts (GRBs) are the most luminous explosions and can be detectable out to the edge of Universe. It has long been thought they can extend the Hubble diagram to very high redshifts. Several correlations between temporal or…

High Energy Astrophysical Phenomena · Physics 2022-01-26 F. Y. Wang , J. P. Hu , G. Q. Zhang , Z. G. Dai

Aims. We investigate the degree of improvement in dark energy constraints that can be achieved by extending Type Ia Supernova (SN Ia) samples to redshifts z > 1.5 with the Hubble Space Telescope (HST), particularly in the ongoing CANDELS…

Cosmology and Nongalactic Astrophysics · Physics 2013-12-10 Vincenzo Salzano , Steven A. Rodney , Irene Sendra , Ruth Lazkoz , Adam G. Riess , Marc Postman , Tom Broadhurst , Dan Coe

We investigate a dynamical reconstruction of the dark energy equation of state parameter by assuming that it satisfies a law of motion described by an autonomous second-order differential equation, with the limit of the cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-25 Andronikos Paliathanasis