Effective potential and Goldstone bosons in de Sitter space

Understand

We investigate nonperturbative infrared effects for the O(N) linear sigma model in de Sitter space using the two-particle irreducible effective action at the Hartree truncation level.

• This approximation resums the infinite series of so-called superdaisy diagrams.
• For the proper treatment of ultraviolet divergences, we first study the renormalization of this approximation on a general curved background.
• Then, we calculate radiatively corrected masses and the effective potential.