A Concept of Assessment of LIV Tests with THESEUS Using the Gamma-Ray Bursts Detected by Fermi/GBM

According to Einstein's special relativity theory, the speed of light in a vacuum is constant for all observers. However, quantum gravity effects could introduce its dispersion depending on the energy of photons. The investigation of the spectral lags between the gamma-ray burst (GRB) light curves recorded in distinct energy ranges could shed light on this phenomenon: the lags could reflect the variation of the speed of light if it is linearlydependent on the photon energy and a function of the GRB redshift. We propose a methodology to start investigating the dispersion law of light propagation in a vacuum using GRB light curves. This technique is intended to be fully exploited using the GRB data collected with THESEUS.

Automated summary

According to Einstein's theory of relativity, the speed of light is constant in a vacuum. However, quantum gravity effects may cause dispersion in the speed of light depending on photon energy. Studying the spectral lags between gamma-ray burst (GRB) light curves recorded at different energy ranges can provide insights into this phenomenon, if the speed of light is linearly dependent on photon energy and a function of GRB redshift. We propose a methodology using GRB light curves to investigate the dispersion law of light propagation in a vacuum, with the intention of utilizing GRB data collected by THESEUS.