Lorentz invariance violation and chemical composition of ultra high energy cosmic rays

We propose that local Lorentz invariance is spontaneously violated at high energies, due to a nonvanishing vacuum expectation value of a vector field ϕμ, as a possible explanation of the observation of ultra-high energy cosmic rays with an energy above the GZK cutoff. Certain consequences of spontaneous breaking of Lorentz invariance in cosmology are discussed.

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Relativity in cosmologically preferred frame and the UHECR paradox

BIBECHANA ◽

10.3126/bibechana.v11i0.10375 ◽

2014 ◽

Vol 11 ◽

pp. 17-24

Author(s):

Saroj Nepal

Keyword(s):

Special Relativity ◽

Rest Frame ◽

Lorentz Invariance ◽

Cosmic Ray ◽

High Energy ◽

Ultra High Energy ◽

High Energy Cosmic Rays ◽

Preferred Frame ◽

Invariance Violation ◽

The Universe

The Greisen-Zatsepin-Kuzmin (GZK) cutoff (5 × 1019eV) of special relativity in the observed ultra high energy cosmic rays (UHECR) spectrum is one of the most puzzling paradoxes in physics. Experimentally a number of cosmic ray events have been detected above this GZK limit which is known as UHECR paradox. We propose a resolution of this paradox through a modification of the relativistic kinematics keeping in mind that it should not lead to predictions different from those of special relativity in the well tested domains. It is shown that theoretical limit in UHECR spectrum can be explained in the framework of Lorentz invariance violation (LIV) theories which assume the existence of a preferred frame. The present paper proposes that the velocity of the solar system with respect to the rest frame of the universe plays a role in explaining the paradox. DOI: http://dx.doi.org/10.3126/bibechana.v11i0.10375 BIBECHANA 11(1) (2014) 17-24

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ULTRA-HIGH ENERGY COSMIC RAYS AND VIOLATION OF LORENTZ INVARIANCE INDUCED BY EXTERNAL FIELD

Quantum Aspects of Beam Physics 2003 ◽

10.1142/9789812702333_0034 ◽

2004 ◽

Author(s):

HUMITAKA SATO

Keyword(s):

Cosmic Rays ◽

External Field ◽

Lorentz Invariance ◽

High Energy ◽

Ultra High Energy ◽

High Energy Cosmic Rays ◽

Violation Of Lorentz Invariance

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Predictions of Ultra-High Energy Cosmic Ray Propagation in the Context of Homogeneously Modified Special Relativity

Symmetry ◽

10.3390/sym12121961 ◽

2020 ◽

Vol 12 (12) ◽

pp. 1961

Author(s):

Marco Danilo Claudio Torri ◽

Lorenzo Caccianiga ◽

Armando di Matteo ◽

Andrea Maino ◽

Lino Miramonti

Keyword(s):

Special Relativity ◽

Lorentz Invariance ◽

Cosmic Ray ◽

High Energy ◽

Ultra High Energy ◽

Attenuation Length ◽

High Energy Cosmic Rays ◽

Invariance Violation ◽

The Universe ◽

Interaction Probability

Ultra high energy cosmic rays (UHECRs) may interact with photon backgrounds and thus the universe is opaque to their propagation. Many Lorentz Invariance Violation (LIV) theories predict a dilation of the expected horizon from which UHECRs can arrive to Earth, in some case even making the interaction probability negligible. In this work, we investigate this effect in the context of the LIV theory that goes by the name of Homogeneously Modified Special Relativity (HMSR). In this work, making use of a specifically modified version of the SimProp simulation program in order to account for the modifications introduced by the theory to the propagation of particles, the radius of the proton opacity horizon (GZK sphere), and the attenuation length for the photopion production process are simulated and the modifications of these quantities introduced by the theory are studied.

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