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Related papers: Constraining Lorentz Violation with Fermi

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Knowledge of the bulk Lorentz factor $\Gamma_{0}$ of GRBs allows us to compute their comoving frame properties shedding light on their physics. Upon collisions with the circumburst matter, the fireball of a GRB starts to decelerate,…

High Energy Astrophysical Phenomena · Physics 2018-01-31 G. Ghirlanda , F. Nappo , G. Ghisellini , A. Melandri , G. Marcarini , L. Nava , O. S. Salafia , S. Campana , R. Salvaterra

In the framework of special relativity, all particles are point-like or string-like. This nature of particles has caused the divergence difficulties in quantum field, string and superstring theories. In the framework of special relativity,…

General Physics · Physics 2007-05-23 Jian-Miin Liu

The properties of gamma-ray bursts (GRBs) that are inferred from observations depend on the value of the bulk Lorentz factor, $\Gamma$. Consequently, accurately estimating it is an important aim. In this work, we present a method of…

High Energy Astrophysical Phenomena · Physics 2025-06-12 Oscar Wistemar , Felix Ryde , Filip Alamaa

A number of works have claimed detections of a turn-over in the spectral lag data for individual Gamma-Ray Bursts (GRBs), caused by an energy-dependent speed of light, which could be a possible manifestation of Lorentz invariance violation…

High Energy Astrophysical Phenomena · Physics 2021-05-13 Rajdeep Agrawal , Haveesh Singirikonda , Shantanu Desai

The physical origin of the >0.1 GeV emission detected from Gamma-Ray Bursts (GRBs) by the Fermi satellite has not yet been completely understood. In this work we consider the GeV light curves of ten GRBs with measured redshift detected by…

High Energy Astrophysical Phenomena · Physics 2015-06-22 L. Nava , G. Vianello , N. Omodei , G. Ghisellini , G. Ghirlanda , A. Celotti , F. Longo , R. Desiante , R. Barniol Duran

Fast radio bursts (FRBs) are astronomical transients with millisecond timescales occurring at cosmological distances. The observed time lag between different energies of each FRB is well described by the inverse-square law of the observed…

Most Gamma-Ray Bursts (GRBs) detected by the Fermi Gamma-ray Space Telescope exhibit a delay of up to about 10 seconds between the trigger time of the hard X-ray signal as measured by the Fermi GBM and the onset of the MeV-GeV counterpart…

High Energy Astrophysical Phenomena · Physics 2015-06-19 Gianluca Castignani , Dafne Guetta , Elena Pian , Lorenzo Amati , Simonetta Puccetti , Simone Dichiara

Fermi Gamma ray Space Telescope measurements of spectra, variability time scale, and maximum photon energy give lower limits to the apparent jet powers and, through gammagamma opacity arguments, the bulk Lorentz factors of relativistic…

High Energy Astrophysical Phenomena · Physics 2010-12-01 Charles D. Dermer , Soebur Razzaque

In quantum gravity, a foamy structure of space-time leads to Lorentz invariance violation (LIV). As the most energetic astrophysical processes in the Universe, gamma-ray bursts (GRBs) provide an effective way to probe quantum gravity…

High Energy Astrophysical Phenomena · Physics 2016-11-22 Zhe Chang , Xin Li , Hai-Nan Lin , Yu Sang , Ping Wang , Sai Wang

Modern ideas in quantum gravity predict the possibility of Lorenz Invariance Violation (LIV) manifested e.g. by energy dependent modification of standard relativistic dispersion relation. In a recent paper Jacob and Piran proposed that time…

Astrophysics · Physics 2009-06-30 Marek Biesiada , Aleksandra Piórkowska

Since the discovery of the cosmological origin of GRBs there has been growing interest in using these transient events to probe the quantum gravity energy scale in the range 10^16--10^19 GeV, up to the Planck mass scale. This energy scale…

Astrophysics · Physics 2009-11-10 Steven E. Boggs , Cornelia B. Wunderer , Kevin Hurley , Wayne Coburn

For a sample of Swift and Fermi GRBs, we show that the minimum variability timescale and the spectral lag of the prompt emission is related to the bulk Lorentz factor in a complex manner: For small $\Gamma$'s, the variability timescale…

High Energy Astrophysical Phenomena · Physics 2015-05-27 E. Sonbas , G. A. MacLachlan , K. S. Dhuga , P. Veres , A. Shenoy , T. N. Ukwatta

We study possible Lorentz violations by means of gamma-ray bursts (GRB) with special focus on the Large Array Telescope (LAT) of GLAST. We simulate bursts with gtobssim and introduce a Lorentz violating term in the arrival times of the…

Astrophysics · Physics 2009-07-07 Raphael Lamon

Experimental observations indicate that gamma-ray bursts (GRB) and high-energy neutrino bursts may travel at different speeds with a typical delay measured at the order of hours or days. We discuss two potential interpretations for the GRB…

High Energy Astrophysical Phenomena · Physics 2021-01-15 Masud Chaichian , Iver Brevik , Markku Oksanen

The empirical evidences in favor of the hypothesis that the speed of light decreases by a few centimeters per second each year are examined. Lunar laser ranging data are found to be consistent with this hypothesis, which also provides a…

General Physics · Physics 2009-12-16 Yves-Henri Sanejouand

We study the emission observed at energies greater than 100 MeV of 11 Gamma Ray Bursts (GRBs) detected by the Fermi/Large Area Telescope (LAT) until October 2009. The GeV emission has three main properties: (i) its duration is often longer…

High Energy Astrophysical Phenomena · Physics 2015-05-14 G. Ghisellini , G. Ghirlanda , L. Nava , A. Celotti

As a basic symmetry of Einstein's theory of special relativity, Lorentz invariance has withstood very strict tests. But there are still motivations for such tests. Firstly, many theories of quantum gravity suggest violations of Lorentz…

High Energy Astrophysical Phenomena · Physics 2022-10-06 Jun-Jie Wei

GRB 190114C is the first gamma-ray burst detected at Very High Energies (VHE, i.e. >300 GeV) by the MAGIC Cherenkov telescope. The analysis of the emission detected by the Fermi satellite at lower energies, in the 10 keV -- 100 GeV energy…

High Energy Astrophysical Phenomena · Physics 2019-06-05 M. E. Ravasio , G. Oganesyan , O. S. Salafia , G. Ghirlanda , G. Ghisellini , M. Branchesi , S. Campana , S. Covino , R. Salvaterra

One of the concepts of Relativity theory that challenges conventional intuition the most is time dilation and length contraction. Usual approaches for describing relativistic effects in quantum systems merely postulate the consequences of…

Quantum Physics · Physics 2024-02-27 Esteban Martínez-Vargas

There have been observations, first from the MAGIC Telescope (July 2005) and quite recently (September 2008) from the FERMI Satellite Telescope, on non-simultaneous arrival of high-energy photons from distant celestial sources. In each…

High Energy Astrophysical Phenomena · Physics 2010-05-28 Nick E. Mavromatos
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