In this book we study the problem of moduli stabilisation in a cosmological context of string theory. Motivated by the moduli stabilisation problem, we introduce for the first time chameleon fields, so named because their masses and values depend sensitively on the local matter density.
We show that such fields can evade all local tests of the equivalence principle and we make predictions for near-future tests of gravity in space while driving the current phase of cosmic accelerated expansion. We then study string corrections to racetrack inflation, a proposal for inflationary dynamics in...

After almost a century, the field of quantum gravity remains as difficult and inspiring as ever. Today, it finds itself a field divided, with two major contenders dominating: string theory, the leading exemplification of the covariant quantization program; and loop quantum gravity, the canonical scheme based on Dirac's constrained Hamiltonian quantization. However, there are now a number of other innovative schemes providing promising new avenues. Encapsulating the latest debates on this topic, this book details the different approaches to understanding the very nature of space and time. It...