COSMOLOGY WITH PSEUDO-NAMBU–GOLDSTONE BOSONS
Abstract
Pseudo-Nambu–Goldstone bosons (pNGBs) are simple and elegant candidates for radiatively stable models of quintessence and inflation. In this brief review, we first examine the observational status of pNGB-driven quintessence and inflation. We then discuss the construction of theoretically as well as observationally viable models of cosmological pNGBs. Special emphasis will be given to the constructions of models compatible with the requirements from String Theory.