The graceful exit in string cosmology

C Cartier, EJ Copeland, R Madden - Journal of High Energy …, 2000 - iopscience.iop.org
We re-examine the graceful exit problem in the pre-Big Bang scenario of string cosmology,
by considering the most general time-dependent classical correction to the lagrangean with …

Cosmology with curvature-saturated gravitational Lagrangian R

H Kleinert, HJ Schmidt - General Relativity and Gravitation, 2002 - Springer
We argue that the Lagrangian for gravity should remain bounded at large curvature, and
interpolate between the weak-field tested Einstein-Hilbert Lagrangian ℒ EH= R/16 πG and a …

Graceful exit from inflation using quantum cosmology

P Pinto-Neto, R Colistete Jr - Physics Letters A, 2001 - Elsevier
A massless scalar field without self-interaction and string coupled to gravity is quantized in
the framework of quantum cosmology using the Bohm–de Broglie interpretation. Gaussian …

Bianchi type I cosmologies in arbitrary dimensional dilaton gravities

CM Chen, T Harko, MK Mak - Physical Review D, 2000 - APS
We study the low energy string effective action with an exponential type dilaton potential and
vanishing torsion in a Bianchi type I space-time geometry. In the Einstein and string frames …

Anisotropic four-dimensional Neveu-Schwarz–Neveu-Schwarz string cosmology

CM Chen, T Harko, MK Mak - Physical Review D, 2001 - APS
An anisotropic (Bianchi type I) cosmology is considered in the four-dimensional Neveu-
Schwarz–Neveu-Schwarz (NS–NS) sector of low-energy effective string theory coupled to a …