English   español  
Por favor, use este identificador para citar o enlazar a este item: http://hdl.handle.net/10261/16327
Compartir / Impacto:
Estadísticas
Add this article to your Mendeley library MendeleyBASE
 |  Ver citas en Google académico
Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL
Título

Physical time and other conceptual issues of quantum gravity on the example of loop quantum cosmology

AutorKamiński, Wojciech; Lewandowski, Jerzy; Pawłowski, Tomasz
Palabras clave[PACS] Lower dimensional models; minisuperspace models
[PACS] Loop quantum gravity, quantum geometry, spin foams
[PACS] Quantum cosmology
Fecha de publicación16-ene-2009
EditorInstitute of Physics Publishing
CitaciónClassical and Quantum Gravity, 26 (3): 035012 (2009)
ResumenSeveral conceptual aspects of quantum gravity (QG) are studied on the example of the homogeneous isotropic loop quantum cosmology (LQC) model. In particular: (i) the proper time of the comoving observers is shown to be a quantum operator and a quantum spacetime metric tensor operator is derived. (ii) Solutions of the quantum scalar constraint for two different choices of the lapse function are compared and contrasted. In particular it is shown that in the case of a model with massless scalar field and cosmological constant Λ, the physical Hilbert spaces constructed for two choices of lapse are the same for Λ < 0 while they are significantly different for Λ > 0. (iii) The mechanism of the singularity avoidance is analyzed via detailed studies of an energy density operator, whose essential spectrum was shown to be an interval [0, ρcr], where ρcr ≈ 0.41ρPl. (iv) The relation between the kinematical and the physical quantum geometry is discussed on the level of relation between observables.
Descripción20 pags. ; appendix
Versión del editorhttp://dx.doi.org/doi:10.1088/0264-9381/26/3/035012
URIhttp://hdl.handle.net/10261/16327
DOIdoi:10.1088/0264-9381/26/3/035012
ISSN0264-9381
Aparece en las colecciones: (CFMAC-IEM) Artículos
Ficheros en este ítem:
No hay ficheros asociados a este ítem.
Mostrar el registro completo
 


NOTA: Los ítems de Digital.CSIC están protegidos por copyright, con todos los derechos reservados, a menos que se indique lo contrario.