toggle visibility Search & Display Options

Select All    Deselect All
 |   | 
Details
   print
  Records Links
Author (up) Ferreiro, A.; Pla, S. url  doi
openurl 
  Title Adiabatic regularization and preferred vacuum state for the lambda phi^4 field theory in cosmological spacetimes Type Journal Article
  Year 2022 Publication Physical Review D Abbreviated Journal Phys. Rev. D  
  Volume 106 Issue 6 Pages 065015 - 12pp  
  Keywords  
  Abstract We extend the method of adiabatic regularization by introducing an arbitrary parameter μfor a scalar field with quartic self-coupling in a Friedmann-Lemaitre-Robertson-Walker spacetime at one-loop order. The subtraction terms constructed from this extended version allow us to define a preferred vacuum state at a fixed time ri 1/4 ri0 for this theory. We compute this vacuum state for two commonly used background fields in cosmology, specially in the context of preheating. We also give a possible prescription for an adequate value for mu.  
  Address [Ferreiro, Antonio] Dublin City Univ, Ctr Astrophys & Relat, Sch Math Sci, Dublin, Ireland, Email: antonio.ferreiro@dcu.ie;  
  Corporate Author Thesis  
  Publisher Amer Physical Soc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2470-0010 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000862258200010 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 5382  
Permanent link to this record
 

 
Author (up) Ferreiro, A.; Torrenti, F. url  doi
openurl 
  Title Ultraviolet-regularized power spectrum without infrared distortions in cosmological spacetimes Type Journal Article
  Year 2023 Publication Physics Letters B Abbreviated Journal Phys. Lett. B  
  Volume 840 Issue Pages 137868 - 6pp  
  Keywords  
  Abstract We reexamine the regularization of the two-point function of a scalar field in a Friedmann-Lemaitre-Robertson-Walker (FLRW) spacetime. Adiabatic regularization provides a set of subtraction terms in momentum space that successfully remove its ultraviolet divergences at coincident points, but can significantly distort the power spectrum at infrared scales, especially for light fields. In this work we propose, by using the intrinsic ambiguities of the renormalization program, a new set of subtraction terms that minimize the distortions for scales k less than or similar to M, with M an arbitrary mass scale. Our method is consistent with local covariance and equivalent to general regularization methods in curved spacetime. We apply our results to the regularization of the power spectrum in de Sitter space: while the adiabatic scheme yields exactly Delta((reg))(phi) = 0 for a massless field, our proposed prescription recovers the standard scale-invariant result Delta((reg))(phi) similar or equal to H-2/(4 pi(2)) at super-horizon scales.  
  Address [Ferreiro, Antonio] Dublin City Univ, Ctr Astrophys & Relat, Sch Math Sci, Dublin 9, Ireland, Email: antonio.ferreiro@dcu.ie;  
  Corporate Author Thesis  
  Publisher Elsevier Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0370-2693 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000968486900001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 5514  
Permanent link to this record
Select All    Deselect All
 |   | 
Details
   print

Save Citations:
Export Records:
ific federMinisterio de Ciencia e InnovaciĆ³nAgencia Estatal de Investigaciongva