PIRSA:10100069

Particle decay in the de Sitter universe

Moschella, U. (2010). Particle decay in the de Sitter universe . Perimeter Institute. https://pirsa.org/10100069

Moschella, Ugo. Particle decay in the de Sitter universe . Perimeter Institute, Oct. 28, 2010, https://pirsa.org/10100069 

          @misc{ pirsa_PIRSA:10100069,
            doi = {10.48660/10100069},
            url = {https://pirsa.org/10100069},
            author = {Moschella, Ugo},
            keywords = {Cosmology},
            language = {en},
            title = {Particle decay in the de Sitter universe },
            publisher = {Perimeter Institute},
            year = {2010},
            month = {oct},
            note = {PIRSA:10100069 see, \url{https://pirsa.org}}
          }

Ugo Moschella

University of Insubria

Talk number
PIRSA:10100069
Collection
Talk Type
Subject
Abstract
We study particle decay in the de Sitter spacetime as given by first order perturbation theory in an interacting quantum field theory. We discuss first a general construction of bosonic two-point functions, including a recently discovered class of tachyonic theories that do exist in the de Sitter spacetime at discrete negative values of the squared mass parameter and have no Minkowskian counterpart. We show then that for fields with masses above a critical mass $m_c$ there is no such thing as particle stability, so that decays forbidden in flat space-time do occur there. The lifetime of such a particle also turns out to be independent of its velocity when that lifetime is comparable with de Sitter radius. For particles with lower mass is yet not completely solved. We show however that the masses of their decay products should obey quantification rules.