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Related papers: Fermi acceleration under Lorentz invariance violat…

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We examine what the absorbed spectra of extra-galactic TeV gamma-ray sources, such as blazars, would look like in the presence of Lorentz invariance violation (LIV). Pair-production with the extra-galactic background light modifies the…

Astrophysics · Physics 2008-12-30 Uri Jacob , Tsvi Piran

Fermi acceleration is the process of energy transfer from massive objects in slow motion to light objects that move fast. The model for such process is a time-dependent Hamiltonian system. As the parameters of the system change with time,…

Chaotic Dynamics · Physics 2015-03-17 Tiago Pereira , Dmitry Turaev

A high energy power law is a common feature in the spectra of many astrophysical objects. We show that the photons in a relativistic plasma with a variable Lorentz factor go through repeated scattering with electrons to gain energy. The…

High Energy Astrophysical Phenomena · Physics 2023-02-01 Mukesh K. Vyas , Asaf Pe'er

Neutrinos are the fundamental particles, blind to all kind of interactions except the weak and gravitational. Hence, they can propagate very long distances without any deviation. This characteristic property can thus provide an ideal…

High Energy Physics - Phenomenology · Physics 2020-05-20 Rudra Majhi , Soumya C , Rukmani Mohanta

The effect of quantum gravity can bring a tiny light speed variation which is detectable through energetic photons propagating from gamma ray bursts (GRBs) to an observer such as the space observatory. Through an analysis of the energetic…

High Energy Physics - Phenomenology · Physics 2016-09-07 Haowei Xu , Bo-Qiang Ma

Putting constraints on a possible Lorentz Invariance Violation (LIV) from astrophysical sources such as gamma-ray bursts (GRBs) is essential for finding evidences of new theories of quantum gravity (QG) that predict an energy-dependent…

General Relativity and Quantum Cosmology · Physics 2023-10-02 Denitsa Staicova

The energy spectrum of neutrino-induced upward-going muons in MACRO was analysed in terms of special relativity principles violating effects, keeping standard mass-induced atmospheric neutrino oscillations as the dominant source of nu_mu…

High Energy Physics - Experiment · Physics 2008-11-26 M. Giorgini

We consider the implications of Lorentz-invariance violation (LIV) on cosmogenic neutrino observations, with particular focus on the constraints imposed on several well-developed models for ultra-high energy cosmogenic neutrino production…

In the present work, we study a fermionic Lorentz invariance violation (LIV) theory with a CPT-even extension and analyze its impact on the Casimir effect under the MIT bag boundary condition model in a low-dimensional setting, where…

High Energy Physics - Theory · Physics 2025-11-13 K. E. L. de Farias , M. A. Anacleto , Iver Brevik , F. A. Brito , E. Passos , Amilcar Queiroz , João R. L. Santos

We consider two alternative dark energy models: a Lorentz invariance preserving model with a nonminimally coupled scalar field and a Lorentz invariance violating model with a minimally coupled scalar field. We study accelerated expansion…

General Relativity and Quantum Cosmology · Physics 2008-12-18 Kourosh Nozari , S. Davood Sadatian

We point out that violation of Lorentz invariance affects the interaction of high-energy photons with the Earth's atmosphere and magnetic field. In certain parameter region this interaction becomes suppressed and the photons escape…

High Energy Astrophysical Phenomena · Physics 2014-07-01 Grigory Rubtsov , Petr Satunin , Sergey Sibiryakov

Ultrahigh energy cosmic rays that produce giant extensive showers of charged particles and photons when they interact in the Earth's atmosphere provide a unique tool to search for new physics. Of particular interest is the possibility of…

High Energy Astrophysical Phenomena · Physics 2009-08-17 Floyd W. Stecker , Sean T. Scully

If Lorentz violation exists, it will affect the thresholds for pair creation processes. Lorentz-violating operators that change the maximum velocities of charged particles may increase or decrease the extinction rate of gamma-rays moving…

High Energy Physics - Phenomenology · Physics 2008-11-26 Brett Altschul

One of the cornerstones of special relativity is the postulate that all observers measure exactly the same photon speeds independently on the photon energies. However, a hypothesized structure of spacetime may alter this conclusion at…

High Energy Physics - Phenomenology · Physics 2019-08-14 Vlasios Vasileiou

We consider the acceleration of energetic particles by Fermi processes (i.e., diffusive shock acceleration, second order Fermi acceleration, and gradual shear acceleration) in relativistic astrophysical jets, with particular attention given…

Astrophysics · Physics 2008-11-26 Frank M. Rieger , Valenti Bosch-Ramon , Peter Duffy

Observations of energy-dependent photon time delays from distant flaring sources provide significant constraints on Lorentz Invariance Violation (LIV). Such effects originate from modified vacuum dispersion relations, causing differences in…

High Energy Astrophysical Phenomena · Physics 2025-08-06 Merce Guerrero , Anna Campoy-Ordaz , Robertus Potting , Markus Gaug

We examine the first order Fermi acceleration on the presumption that supernova remnant shocks cross ambient magnetic fields with various angles. These oblique shocks accelerate particles more efficiently than the parallel shocks and…

Astrophysics · Physics 2009-10-31 K. Kobayakawa , Y. S. Honda , T. Samura

We explore the possibility to geometrize the interaction of massive fermions with the quantum structure of space-time, trying to create a theoretical background, in order to explain what some recent experimental results seem to implicate on…

High Energy Physics - Phenomenology · Physics 2019-09-24 M. D. C. Torri , S. Bertini , M. Giammarchi , L. Miramonti

There are still some {significant and} unanswered questions about the {incredible} {very high energy (VHE)} $\gamma$-ray signatures. To help understand the mechanism, focusing on the linear and quadratic perturbation mode for the subluminal…

High Energy Astrophysical Phenomena · Physics 2023-04-19 Y. G. Zheng , S. J. Kang , K. R. Zhu , C. Y. Yang , J. M. Bai

We obtain modified dispersion relations by requiring the vanishing of determinant of inverse of modified photon propagators in Lorentz invariance violation (LIV) theory. Inspired by these dispersion relations, we give a more general…

High Energy Physics - Phenomenology · Physics 2010-01-18 Zhi Xiao , Bo-Qiang Ma