TASI/PiTP/ISS Lectures on Moduli and Microphysics

TL;DR

This paper reviews the mechanisms of moduli stabilization in string theory, discussing classical and non-perturbative forces, and explores their implications for (A)dS solutions and microphysical entropy, including recent velocity-dependent effects.

Contribution

It provides a comprehensive overview of moduli stabilization methods, including new models and detailed entropy predictions, integrating classical, flux, brane, and non-perturbative effects.

Findings

Detailed predictions for microphysical entropy in (A)dS solutions

Analysis of classical and non-perturbative stabilization mechanisms

Inclusion of velocity-dependent effects in moduli dynamics

Abstract

I review basic forces on moduli that lead to their stabilization, for example in the supercritical and KKLT models of de Sitter space in string theory, as well as an $AdS_4\times S^3\times S^3$ model I include which is not published elsewhere. These forces come from the classical dilaton tadpole in generic dimensionality, internal curvature, fluxes, and branes and orientifolds as well as non-perturbative effects. The resulting (A)dS solutions of string theory make detailed predictions for microphysical entropy, whose leading behavior we exhibit on the Coulomb branch of the system. Finally, I briefly review recent developments concerning the role of velocity-dependent effects in the dynamics of moduli. These lecture notes are based on material presented at various stages in the 1999 TASI, 2002 PiTP, 2003 TASI, and 2003 ISS schools.