Abstract
One of the key open questions in fundamental physics concerns the supposed quantum structure of spacetime. New physical effects are expected as residual evidence of a more fundamental theory of nature. In this fundamental theory the underlying physical symmetries could be modified by the quantized structure of geometry. One of the most important symmetries in our description of Physics is Lorentz Invariance (LI). Nowadays LI is at the root of our understanding of nature and underlies its physical description. Even if there is no definitive evidence to sustain departures from this symmetry, there are consistent points indicating that Lorentz Invariance Violation (LIV) can be a consequence of quantum gravity. A critical issue concerns therefore the necessity of testing this fundamental symmetry validity. Ultra High Energy Cosmic Rays (UHECR) and neutrino flavor oscillation are promising physical processes of investigation for LIV, since the high energy involved and the interaction of different particle species.
Highlights
The investigation for Lorentz Invariance Violations is motivated by the necessity of searching for residual quantum gravity effects at the Planck-scale
Homogeneously Modified Special Relativity (HMSR) represents a new Lorentz Invariance Violation (LIV) theoretical model with the original feature of preserving the covariance with respect to rotations and boosts. This constitutes a great advantage for experiments, since the theory does not require the introduction of a preferred reference frame
The foreseen phenomenological effects are expected to be valid in every reference frame and the spacetime isotropy results preserved, even if with respect to an amended formulation of the kinematical symmetry group, i.e. the Lorentz/Poincare group
Summary
The investigation for Lorentz Invariance Violations is motivated by the necessity of searching for residual quantum gravity effects at the Planck-scale. Spacetime geometry In all LIV theories the effects of the supposed quantum structure of spacetime manifest itself modifying massive particles kinematics [1, 2, 3, 4, 5, 6, 7, 8] This means that the dispersion relations result modified. It is necessary to introduce a new mathematical formalism to conduct computations between physical quantities related to different interacting particles This result is obtained constructing the generalized tetrad (vierbein) that presents an explicit dependence on the particle momentum and are defined in order to obtain: gμν (x ) = eμa(p(x )) ηab eνb(p(x )). The 1 and the MAV for every massive particle becomes:
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
