String Cosmology and the Breakdown of Local Effective Field Theory

Abstract

Most current cosmological models of the very early universe are based on local point particle effective field theories coupled to gravity. I will discuss some conceptual limitations of this approach and argue that an improved description of the early universe needs to go beyond this framework. I will outline a couple of ideas based on superstring theory.

Comments: Invited talk at the workshop "Quantum Gravity, Higher Derivatives and Nonlocality", March 9 - 13 2021; 12 pages