vai al contenuto della pagina vai al menu di navigazione

Suppressing Quantum Fluctuations in Classicalization

by Dr. Alexander Vikman, CERN and Stanford University (USA)

May 16, 2013 from 04:00 PM to 06:00 PM

Where Aula Teorici - Irnerio

Contact Name Fiorenzo Bastianelli

Add to your calendar

Abstract: We study vacuum quantum fluctuations of simple Nambu-Goldstone bosons - derivatively coupled single scalar-field theories possessing shift-symmetry in field space. We argue that quantum fluctuations of the interacting field can be drastically suppressed with respect to the free-field case. Moreover, the power-spectrum of these fluctuations can soften to become red for sufficiently small scales. In quasiclassical approximation, we demonstrate that this suppression can only occur for those theories that admit such classical static backgrounds around which small perturbations propagate faster than light. Thus, a quasiclassical softening of quantum fluctuations is only possible for theories which classicalize instead of having a usual Lorentz invariant and local Wilsonian UV- completion. We illustrate our analysis by estimating the quantum fluctuations for the DBI-like theories.