Abstract:
In some models of quantum-gravity-inspired quantum spacetimes, relativistic symmetries are modified (deformed or broken) at the Planck scale, so that spacetime itself might behave like a dispersive medium for particle propagation (in-vacuo dispersion). The long (cosmological) distance traveled by ultra-relativistic particles emitted by transient astrophysical sources could provide a huge source of amplification for the tiny (Planckian) effects, offering a precious opportunity for experimental tests. I present a brief introduction to these phenomenological studies, with particular attention to scenarios based on k-Minkowski/k-Poincaré noncommutative spacetime, and discuss some recent results concerning tests of in-vacuo dispersion in the observation of gamma-ray-bursts photons and (IceCube) astrophysical neutrinos