| Records |
| Author |
Ferreiro, A.; Torrenti, F. |
| 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 |
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Pages |
137868 - 6pp |
| Keywords |
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| 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 |
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Thesis |
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| Publisher |
Elsevier |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title  |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0370-2693 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
WOS:000968486900001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
5514 |
| Permanent link to this record |
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| Author |
Ferreiro, A.; Monin, S.; Torrenti, F. |
| Title |
Physical scale adiabatic regularization in cosmological spacetimes |
Type |
Journal Article |
| Year |
2024 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
| Volume |
109 |
Issue |
4 |
Pages |
045015 - 16pp |
| Keywords |
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| Abstract |
We develop a new regularization method for the stress -energy tensor and the two -point function of free quantum scalar fields propagating in cosmological spacetimes. We proceed by extending the adiabatic regularization scheme with the introduction of two additional mass scales. By setting them to the order of the physical scale of the studied scenario, we obtain ultraviolet -regularized quantities that do not distort the power spectra amplitude at the infrared scales amplified by the expansion of the Universe. This is not ensured by the standard adiabatic approach. We also show how our proposed subtraction terms can be interpreted as a renormalization of coupling constants in the Einstein equations. We finally illustrate our proposed regularization method in two scenarios of cosmological interest: de Sitter inflation and geometric reheating. |
| Address |
[Ferreiro, Antonio] Univ Utrecht, Freudenthal Inst, NL-3584CC Utrecht, Netherlands, Email: antonio.ferreiro@ru.nl; |
| Corporate Author |
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Thesis |
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| Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
2470-0010 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
WOS:001180335500003 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
6015 |
| Permanent link to this record |
