Robustness of inflation to inhomogeneous initial conditions
We consider the effects of inhomogeneous initial conditions in both the scalar field profile and the extrinsic curvature on different inflationary models. In particular, we compare the robustness of small field inflation to that of large field inflation, using numerical simulations with Einstein gra...
| Main Authors: | , , , , , |
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| Format: | Journal article |
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IOP Publishing
2017
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| _version_ | 1826288001773207552 |
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| author | Clough, K Lim, E Dinunno, B Fischler, W Flauger, R Paban, S |
| author_facet | Clough, K Lim, E Dinunno, B Fischler, W Flauger, R Paban, S |
| author_sort | Clough, K |
| collection | OXFORD |
| description | We consider the effects of inhomogeneous initial conditions in both the scalar field profile and the extrinsic curvature on different inflationary models. In particular, we compare the robustness of small field inflation to that of large field inflation, using numerical simulations with Einstein gravity in 3+1 dimensions. We find that small field inflation can fail in the presence of subdominant gradient energies, suggesting that it is much less robust to inhomogeneities than large field inflation, which withstands dominant gradient energies. However, we also show that small field inflation can be successful even if some regions of spacetime start out in the region of the potential that does not support inflation. In the large field case, we confirm previous results that inflation is robust if the inflaton occupies the inflationary part of the potential. Furthermore, we show that increasing initial scalar gradients will not form sufficiently massive inflation-ending black holes if the initial hypersurface is approximately flat. Finally, we consider the large field case with a varying extrinsic curvature K, such that some regions are initially collapsing. We find that this may again lead to local black holes, but overall the spacetime remains inflationary if the spacetime is open, which confirms previous theoretical studies. |
| first_indexed | 2024-03-07T02:07:09Z |
| format | Journal article |
| id | oxford-uuid:9f5dfe95-0e54-4990-a4b9-3510690bd289 |
| institution | University of Oxford |
| last_indexed | 2024-03-07T02:07:09Z |
| publishDate | 2017 |
| publisher | IOP Publishing |
| record_format | dspace |
| spelling | oxford-uuid:9f5dfe95-0e54-4990-a4b9-3510690bd2892022-03-27T00:57:09ZRobustness of inflation to inhomogeneous initial conditionsJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:9f5dfe95-0e54-4990-a4b9-3510690bd289Symplectic Elements at OxfordIOP Publishing2017Clough, KLim, EDinunno, BFischler, WFlauger, RPaban, SWe consider the effects of inhomogeneous initial conditions in both the scalar field profile and the extrinsic curvature on different inflationary models. In particular, we compare the robustness of small field inflation to that of large field inflation, using numerical simulations with Einstein gravity in 3+1 dimensions. We find that small field inflation can fail in the presence of subdominant gradient energies, suggesting that it is much less robust to inhomogeneities than large field inflation, which withstands dominant gradient energies. However, we also show that small field inflation can be successful even if some regions of spacetime start out in the region of the potential that does not support inflation. In the large field case, we confirm previous results that inflation is robust if the inflaton occupies the inflationary part of the potential. Furthermore, we show that increasing initial scalar gradients will not form sufficiently massive inflation-ending black holes if the initial hypersurface is approximately flat. Finally, we consider the large field case with a varying extrinsic curvature K, such that some regions are initially collapsing. We find that this may again lead to local black holes, but overall the spacetime remains inflationary if the spacetime is open, which confirms previous theoretical studies. |
| spellingShingle | Clough, K Lim, E Dinunno, B Fischler, W Flauger, R Paban, S Robustness of inflation to inhomogeneous initial conditions |
| title | Robustness of inflation to inhomogeneous initial conditions |
| title_full | Robustness of inflation to inhomogeneous initial conditions |
| title_fullStr | Robustness of inflation to inhomogeneous initial conditions |
| title_full_unstemmed | Robustness of inflation to inhomogeneous initial conditions |
| title_short | Robustness of inflation to inhomogeneous initial conditions |
| title_sort | robustness of inflation to inhomogeneous initial conditions |
| work_keys_str_mv | AT cloughk robustnessofinflationtoinhomogeneousinitialconditions AT lime robustnessofinflationtoinhomogeneousinitialconditions AT dinunnob robustnessofinflationtoinhomogeneousinitialconditions AT fischlerw robustnessofinflationtoinhomogeneousinitialconditions AT flaugerr robustnessofinflationtoinhomogeneousinitialconditions AT pabans robustnessofinflationtoinhomogeneousinitialconditions |