1.5k citations · 22.2k across the 177 of their papers we have counts for
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Exponential potentials and cosmological scaling solutions
Edmund J Copeland, Andrew R Liddle, David Wands
We present a phase-plane analysis of cosmologies containing a barotropic fluid with equation of state , plus a scalar field with an exponential potential $V \pr…
Cosmology of the type IIB superstring
E. J. Copeland, James E. Lidsey, David Wands
The continuous and discrete symmetries of a dimensionally reduced type IIB superstring action are employed to generate four-dimensional cosmological solutions with non-trivial Neve…
Symmetries for generating string cosmologies
E. J. Copeland, James E. Lidsey, David Wands
We discuss the symmetry properties of the low-energy effective action of the type IIB superstring that may be employed to derive four-dimensional solutions. A truncated effective a…
S-duality Invariant Perturbations in String Cosmology
E. J. Copeland, James E. Lidsey, David Wands
We investigate the generation of curvature and isocurvature (dilaton, moduli and axion) perturbations in a general class of axion-dilaton-moduli models,including the pre-big bang s…
Vacuum fluctuations in axion-dilaton cosmologies
E. J. Copeland, Richard Easther, David Wands
We study axion-dilaton cosmologies derived from the low-energy string effective action. We present the classical homogeneous Friedmann-Robertson-Walker solutions and derive the sem…