INFLATIONARY UNIVERSE: A RELATIVISTIC NECESSITY ? Giovanni Zanella Studioso Senior dello Studium Patavinum Università di Padova, Dipartimento di Fisica e Astronomia

Relativistic kinetics Wavefront of light at the time y t Rigid rod Flash of light at the time t =0 1 2 3 c t u c t c t u y t Stationary reference u t x Wavefront of light at the time t Source of light

Cosmic muons crossing the terrestrial atmosphere Starting point 660 m = u t atmosphere top 15 km = u y t Stationary reference Dilated path of the muon at steady kinetic energy µ sea level t = mean life of the muon ( ~ 2.2  s ) u = velocity of the muon from the stationary reference ( ~ c) y t = dilated mean life of the muon u y t = dilated path of the muon u y = velocity measured from the muon vs the stationary reference

Particles in mutual leaving Stationary reference x t = elapsed time for the comoving observer u/2 = velocity of the particle with respect the stationary reference u y = velocity measured from a particle with respect to the other one u y t = dilated distance of the particle

Inflationary Universe M R Stationary reference Particles in mutual leaving Flatness condition

Expansion of the observable Universe Radius (m) STANDARD MODEL 1030 1010 10-10 NOW Inflation 10-30 10-50 10-32 Time (s) 10-35 10-25 10-15 10-5 105 1015 Primordial fireball Appearence of particles