Duality and Cosmology

Self-T-dual Brane Cosmology

We show how T-duality can be implemented with brane cosmology. As a result, we obtain a smooth bouncing cosmology with features similar to the ones of the pre-Big Bang scenario. Also, by allowing T-duality transformations along the time-like direction, we find a static solution that displays an interesting self tuning property. Based on a talk given at the XI Marcel Grossmann Meeting, Berlin 23...

U–duality Covariant M–theory Cosmology

A manifestly U–duality covariant approach to M–theory cosmology is developed and applied to cosmologies in dimensions D = 4, 5. Cosmological properties such as expansion powers and Hubble parameters turn out to be U–duality invariant in certain asymptotic regions. U–duality transformations acting on cosmological solutions, on the other hand, shift the transition time between two asymptotic regi...

Magnetic Monopoles, Duality, and Supersymmetry

These notes present a pedagogical introduction to magnetic monopoles and exact electromagnetic duality in supersymmetric gauge theories. They are based on lectures given at the 1995 Trieste Summer School in High Energy Physics and Cosmology and at the 1995 Busstepp Summer School at Cosener’s House.

Cosmology. Testing gauge/gravity duality on a quantum black hole.

Non-Abelian T-duality in Pre-Big-Bang Cosmology

We study the impact of non-Abelian T-duality transformations on a string based cosmological model. The implementation of the pre-big-bang scenario is investigated. We found a region of the dual phase where such a picture is possible. e-mail: [email protected] e-mail: [email protected] CNRS UPRES-A 6083

Self-T-Dual Brane Cosmology and the Cosmological Constant Problem

We consider a codimension-one brane embedded in a gravity-dilaton bulk action, whose symmetries are compatible with T-duality along the space-like directions parallel to the brane, and the bulk time-like direction. The equations of motions in the string frame allow for a smooth background obtained by the union of two symmetric patches of AdS space. The Poincaré invariance of the solution appear...