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Pre-big-bang in string cosmology
The duality-type symmetries of string cosmology naturally lead us to expect a pre-big-bang phase of accelerated evolution as the dual counterpart of the decelerating expansion era of standardExpand
Phenomenological aspects of the pre-big-bang scenario in string cosmology
I review various aspects of the pre-big-bang scenario and of its main open problems, with emphasis on the role played by the dilaton. Since the dilaton is a compelling consequence of string theory,Expand
Introduction to gravitation
This book is divided into the following chapters: Contents: Geometry and Gravitation; The Formalism of General Relativity; Gravitational Field Equations; The Three Classical Tests of Einstein'sExpand
Elements of string cosmology
Preface Acknowledgements Notation, units and conventions 1. A short review of standard and inflationary cosmology 2. The basic string cosmology equations 3. Conformal invariance and string effectiveExpand
A covariant and gauge invariant formulation of the cosmological "backreaction"
Using our recent proposal for defining gauge invariant averages we give a general-covariant formulation of the so-called cosmological "backreaction". Our effective covariant equations allow us toExpand
Quintessence as a runaway dilaton
We consider a late-time cosmological model based on a recent proposal that the infinite-bare-coupling limit of superstring/M-theory exists and has good phenomenological properties, including aExpand
Relic gravitational waves from string cosmology
A large class of string-cosmology backgrounds leads to a spectrum of relic stochastic gravitational waves, strongly tilted towards high frequencies, and characterized by two basic parameters of theExpand
Light-cone averaging in cosmology: formalism and applications
We present a general gauge invariant formalism for defining cosmological averages that are relevant for observations based on light-like signals. Such averages involve either null hypersurfacesExpand
Homogeneous conformal string backgrounds
We present exact solutions characterized by Bianchi-type I, II, III, V, VI, VI with a four-dimensional metric, space-independent dilaton, and vanishing torsion background, for the low-energy stringExpand