InflaBoot · Bootstrapping Inflationary Cosmology

Bootstrapping Inflationary Cosmology

"Cosmology is the source, but also the adjudicator, of some of the biggest questions in physics. There is growing evidence that the very early universe underwent a period of rapid, approximately de Sitter (dS), inflationary expansion -- providing an elegant explanation for the primordial density fluctuations inferred from observations of the cosmic microwave background and the large-scale structure of the universe. Since the energy scale of inflation could be as high as 10^14 Gev, far beyond the reach of our terrestrial experiments, this would make inflation the highest energy observable natural process. We are therefore presented with a remarkable opportunity to probe the laws of physics at these scales, which thus far have remained rather elusive. In anticipation of increasingly precise observations it is imperative that we understand how to extract information about the laws of physics at such scales. While in recent years there have been significant theoretical advances in our understanding of cosmological correlation functions, we still find it challenging to isolate fundamental physics from them. In particular, we don’t yet have a firm grasp of the rules that govern cosmological correlators, so that, naively, it would appear that anything goes. At the same time, the last few decades has seen significant advances in our understanding of gravitational observables. In particular, the striking notion that Quantum Gravity is “holographic” in nature -- in studying Quantum Gravity, we are led to consider holographic theories for the boundary observables at infinity. The most precise formulation of such a duality is the AdS/CFT correspondence, where boundary observables of Quantum Gravity in asymptotically anti-de Sitter (AdS) space are given by correlation functions of a Conformal Field Theory (CFT) in flat space-time. In this setting, the rules that govern gravitational observables in anti-de Sitter space are given by those of consistent CFTs, for which various powerful techniques have been developed in last decade within the framework of the “Conformal Bootstrap”. By extending this understanding of observables in AdS space to dS, which are related by analytic continuation, this would provide key insights into understanding the ""rules of the game"" for cosmological correlators. This is the overall objective of the project. In particular, to extend Conformal Bootstrap techniques and results that so far have been tailored to physics in anti-de Sitter to physics in de Sitter space."

Data: CORDIS, © European Union