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SUMMARY:Spurious secular growth from loops in de Sitter - Gonzalo Palma (U
 niversidad de Chile\, Santiago)
DTSTART:20250210T130000Z
DTEND:20250210T140000Z
UID:TALK222856@talks.cam.ac.uk
CONTACT:Thomas Colas
DESCRIPTION:A well-established result in QFT in four-dimensional de Sitter
  spacetime states that the vacuum of a massless scalar field lacks a norma
 lizable inner product. This has often been interpreted as evidence that th
 e vacuum cannot remain invariant under the full de Sitter isometry group\,
  suggesting the emergence of time-dependent (secular) growth in correlatio
 n functions computed in inflationary coordinates. However\, the standard q
 uantization of scalar fields in de Sitter spacetime using inflationary coo
 rdinates yields a vacuum state for the massless scalar field that explicit
 ly preserves de Sitter symmetries\, albeit with infrared divergences. In t
 his talk\, I will discuss the computation of n-point correlation functions
  and demonstrate that loop corrections do not further enhance the secular 
 growth of these functions for massless scalars. I will also address the di
 screpancies between our findings and those reported in previous studies.\n
LOCATION:CMS\, Pav. B\, CTC Common Room (B1.19) [Potter Room]
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