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 [Formula Presented] and [Formula Presented] which in turn give [Formula Presented] and [Formula...
Guardado en:
| Autores principales: | , , |
|---|---|
| Formato: | JOUR |
| Acceso en línea: | http://hdl.handle.net/20.500.12110/paper_15507998_v70_n2_p5_Aguirregabiria |
| Aporte de: |
| id |
todo:paper_15507998_v70_n2_p5_Aguirregabiria |
|---|---|
| record_format |
dspace |
| spelling |
todo:paper_15507998_v70_n2_p5_Aguirregabiria2023-10-03T16:23:55Z Phantom k-essence cosmologies Aguirregabiria, J.M. Chimento, L.P. Lazkoz, R. 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 [Formula Presented] and [Formula Presented] which in turn give [Formula Presented] and [Formula Presented] 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. © 2004 The American Physical Society. JOUR info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/2.5/ar http://hdl.handle.net/20.500.12110/paper_15507998_v70_n2_p5_Aguirregabiria |
| institution |
Universidad de Buenos Aires |
| institution_str |
I-28 |
| repository_str |
R-134 |
| collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
| 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 [Formula Presented] and [Formula Presented] which in turn give [Formula Presented] and [Formula Presented] 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. © 2004 The American Physical Society. |
| format |
JOUR |
| author |
Aguirregabiria, J.M. Chimento, L.P. Lazkoz, R. |
| spellingShingle |
Aguirregabiria, J.M. Chimento, L.P. Lazkoz, R. Phantom k-essence cosmologies |
| author_facet |
Aguirregabiria, J.M. Chimento, L.P. Lazkoz, R. |
| author_sort |
Aguirregabiria, J.M. |
| 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 |
| url |
http://hdl.handle.net/20.500.12110/paper_15507998_v70_n2_p5_Aguirregabiria |
| work_keys_str_mv |
AT aguirregabiriajm phantomkessencecosmologies AT chimentolp phantomkessencecosmologies AT lazkozr phantomkessencecosmologies |
| _version_ |
1782024318984650752 |