Noncritical anisotropic Bianchi type I string cosmology with α ′ corrections

We present noncritical Bianchi type I string cosmology solutions in the presence of central charge deficit term Λ. The leading-order string frame curvature appears to be in the high curvature limit Rα′≳1, which underlines the necessity of including higher-order α′ corrections. We give new solutions...

Full description

Saved in:
Bibliographic Details
Published in:Physical review. D 2018-07, Vol.98 (2), Article 026009
Main Authors: Naderi, F., Rezaei-Aghdam, A., Darabi, F.
Format: Article
Language:English
Subjects:
Cosmology
Curvature
Dilatons
Mathematical models
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:We present noncritical Bianchi type I string cosmology solutions in the presence of central charge deficit term Λ. The leading-order string frame curvature appears to be in the high curvature limit Rα′≳1, which underlines the necessity of including higher-order α′ corrections. We give new solutions of two-loop (first-order α′) β-function equations of the σ model with nonzero Λ and the dilaton field in both cases of the absence and presence of a spatially homogeneous H field (H=dB). Also, the evolution of solutions is studied in the Einstein frame, in which the string effective action can transform to Gauss-Bonnet gravity model coupled to a dilaton field with potential. We study explicit examples in first-order α′ with chosen values of appeared constants in the solutions and discuss the cosmological implications.
ISSN:2470-0010
2470-0029
DOI:10.1103/PhysRevD.98.026009