Phantom k-essence cosmologies
We devise a method to obtain a phantom version of FRW k-essence cosmologies with homogeneous k fields by applying form-invariance transformations. It can be seen that the transformation performs the maps H→-H and ρ+p→-(ρ+p), which in turn give γ→-γ and a→a-1. The discussion is presented in a general...
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2004
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| Acceso en línea: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_05562821_v70_n2_p023509_Aguirregabiria http://hdl.handle.net/20.500.12110/paper_05562821_v70_n2_p023509_Aguirregabiria |
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paper:paper_05562821_v70_n2_p023509_Aguirregabiria2023-06-08T15:42:33Z Phantom k-essence cosmologies Chimento, Luis Pascual article cosmos elementary particle mathematical analysis phantom tachyon We devise a method to obtain a phantom version of FRW k-essence cosmologies with homogeneous k fields by applying form-invariance transformations. It can be seen that the transformation performs the maps H→-H and ρ+p→-(ρ+p), which in turn give γ→-γ and a→a-1. The discussion is presented in a general setup, valid for FRW k-essence cosmologies, and then we discuss power-law solutions for illustration purposes. First, we deal with models such that the gradient of the k field is not constant, and they include standard and generalized tachyon cosmologies. We concentrate on the usual tachyon and show that the phantom symmetry involves a change in the potential: and that it generates an extended superaccelerated tachyon field. Then, we turn our attention to models for which the time derivative of the k field is not constant, and we show the transformation can be implemented without changing the potential at all. Fil:Chimento, L.P. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. 2004 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_05562821_v70_n2_p023509_Aguirregabiria http://hdl.handle.net/20.500.12110/paper_05562821_v70_n2_p023509_Aguirregabiria |
| institution |
Universidad de Buenos Aires |
| institution_str |
I-28 |
| repository_str |
R-134 |
| collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
| topic |
article cosmos elementary particle mathematical analysis phantom tachyon |
| spellingShingle |
article cosmos elementary particle mathematical analysis phantom tachyon Chimento, Luis Pascual Phantom k-essence cosmologies |
| topic_facet |
article cosmos elementary particle mathematical analysis phantom tachyon |
| description |
We devise a method to obtain a phantom version of FRW k-essence cosmologies with homogeneous k fields by applying form-invariance transformations. It can be seen that the transformation performs the maps H→-H and ρ+p→-(ρ+p), which in turn give γ→-γ and a→a-1. The discussion is presented in a general setup, valid for FRW k-essence cosmologies, and then we discuss power-law solutions for illustration purposes. First, we deal with models such that the gradient of the k field is not constant, and they include standard and generalized tachyon cosmologies. We concentrate on the usual tachyon and show that the phantom symmetry involves a change in the potential: and that it generates an extended superaccelerated tachyon field. Then, we turn our attention to models for which the time derivative of the k field is not constant, and we show the transformation can be implemented without changing the potential at all. |
| author |
Chimento, Luis Pascual |
| author_facet |
Chimento, Luis Pascual |
| author_sort |
Chimento, Luis Pascual |
| title |
Phantom k-essence cosmologies |
| title_short |
Phantom k-essence cosmologies |
| title_full |
Phantom k-essence cosmologies |
| title_fullStr |
Phantom k-essence cosmologies |
| title_full_unstemmed |
Phantom k-essence cosmologies |
| title_sort |
phantom k-essence cosmologies |
| publishDate |
2004 |
| url |
https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_05562821_v70_n2_p023509_Aguirregabiria http://hdl.handle.net/20.500.12110/paper_05562821_v70_n2_p023509_Aguirregabiria |
| work_keys_str_mv |
AT chimentoluispascual phantomkessencecosmologies |
| _version_ |
1768546757371756544 |