A resolution of the cosmological singularity with orientifolds

• Tipo: Artigo em Revista Científica Internacional
• Data: 2002

Autores

Cornalba, L (Autor) Outra; Costa, MS (Autor) FCUP; Kounnas, C (Autor) Outra

Revista

Título: Nuclear Physics B

Vol. 637

Páginas: 378-394

ISSN: 0550-3213

Editora: Elsevier

Indexação

ISI Web of Knowledge - 120 Citações

Scopus - 118 Citações

Classificação Científica

FOS: Ciências exactas e naturais > Física

Outras Informações

ID Authenticus: P-007-AHQ

DOI: 10.1016/s0550-3213(02)00446-7

Abstract (EN): We propose a new cosmological scenario which resolves the conventional initial singularity problem. The space-time geometry has an unconventional time-like singularity on a lower-dimensional hypersurface, with localized energy density. The natural interpretation of this singularity in string theory is that of negative tension branes, for example the orientifolds of type II string theory. Space-time ends at the orientifolds, and it is divided in three regions: a contracting region with a future cosmological horizon; an intermediate region which ends at the orientifols; and an expanding region separated from the intermediate region by a past cosmological horizon. We study the geometry near the singularity of the proposed cosmological scenario in a specific string model. Using D-brane probes we confirm the interpretation of the brane singularity as an orientifold. The boundary conditions on the orientifolds and the past/future transition amplitudes are well defined. Assuming the trivial vacuum in the past, we derive a thermal spectrum in the future.

Idioma: Inglês

Tipo (Avaliação Docente): Científica