Modified gravity with an exponential function of curvature
Abstract The role of an exponential function of the scalar curvature in the modified gravity is analyzed. Two models are proposed. A toy model that complies with local and cosmological constraints and gives appropriate qualitative description of the cosmic evolution. This model contains a saddle mat...
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| Format: | Article |
| Language: | English |
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SpringerOpen
2020-06-01
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| Series: | European Physical Journal C: Particles and Fields |
| Online Access: | http://link.springer.com/article/10.1140/epjc/s10052-020-8114-4 |
| _version_ | 1828776925923901440 |
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| author | L. N. Granda |
| author_facet | L. N. Granda |
| author_sort | L. N. Granda |
| collection | DOAJ |
| description | Abstract The role of an exponential function of the scalar curvature in the modified gravity is analyzed. Two models are proposed. A toy model that complies with local and cosmological constraints and gives appropriate qualitative description of the cosmic evolution. This model contains a saddle matter-dominant critical point that can evolve towards a late time de Sitter attractor. Initial conditions have been proposed, showing that this toy model has an acceptable matter era and gives an approximate qualitative behavior of cosmic evolution. A second viable model, behaves very close to $$\Lambda $$ Λ CDM at early times and can satisfy local and cosmological constraints. It behaves as $$R-2\Lambda $$ R-2Λ at $$R\rightarrow \infty $$ R→∞ and tends to zero at $$R\rightarrow 0$$ R→0 , containing flat spacetime solution. The model gives viable cosmological trajectories that, as the first model, connect the matter dominated point with a late time de Sitter attractor. The cosmic evolution of the main density parameters in this model is consistent with current observations with an equation of state very close to $$-1$$ -1 . |
| first_indexed | 2024-12-11T16:10:12Z |
| format | Article |
| id | doaj.art-7c9ab9ff470f42ec9c8542630bee4d1a |
| institution | Directory Open Access Journal |
| issn | 1434-6044 1434-6052 |
| language | English |
| last_indexed | 2024-12-11T16:10:12Z |
| publishDate | 2020-06-01 |
| publisher | SpringerOpen |
| record_format | Article |
| series | European Physical Journal C: Particles and Fields |
| spelling | doaj.art-7c9ab9ff470f42ec9c8542630bee4d1a2022-12-22T00:59:05ZengSpringerOpenEuropean Physical Journal C: Particles and Fields1434-60441434-60522020-06-0180611110.1140/epjc/s10052-020-8114-4Modified gravity with an exponential function of curvatureL. N. Granda0Departamento de Fisica, Universidad del ValleAbstract The role of an exponential function of the scalar curvature in the modified gravity is analyzed. Two models are proposed. A toy model that complies with local and cosmological constraints and gives appropriate qualitative description of the cosmic evolution. This model contains a saddle matter-dominant critical point that can evolve towards a late time de Sitter attractor. Initial conditions have been proposed, showing that this toy model has an acceptable matter era and gives an approximate qualitative behavior of cosmic evolution. A second viable model, behaves very close to $$\Lambda $$ Λ CDM at early times and can satisfy local and cosmological constraints. It behaves as $$R-2\Lambda $$ R-2Λ at $$R\rightarrow \infty $$ R→∞ and tends to zero at $$R\rightarrow 0$$ R→0 , containing flat spacetime solution. The model gives viable cosmological trajectories that, as the first model, connect the matter dominated point with a late time de Sitter attractor. The cosmic evolution of the main density parameters in this model is consistent with current observations with an equation of state very close to $$-1$$ -1 .http://link.springer.com/article/10.1140/epjc/s10052-020-8114-4 |
| spellingShingle | L. N. Granda Modified gravity with an exponential function of curvature European Physical Journal C: Particles and Fields |
| title | Modified gravity with an exponential function of curvature |
| title_full | Modified gravity with an exponential function of curvature |
| title_fullStr | Modified gravity with an exponential function of curvature |
| title_full_unstemmed | Modified gravity with an exponential function of curvature |
| title_short | Modified gravity with an exponential function of curvature |
| title_sort | modified gravity with an exponential function of curvature |
| url | http://link.springer.com/article/10.1140/epjc/s10052-020-8114-4 |
| work_keys_str_mv | AT lngranda modifiedgravitywithanexponentialfunctionofcurvature |