Research

Physical Sciences

Title :

Deciphering the Cosmological Bootstrap

Area of research :

Physical Sciences

Focus area :

Theoretical Particle Physics and Cosmology

Principal Investigator :

Dr. Diptimoy Ghosh, Indian Institute of science Education And Research (IIsER), Pune, Maharashtra

Timeline Start Year :

2024

Timeline End Year :

2027

Contact info :

Details

Executive Summary :

Inflation is a simple but profound concept that can be used to predict observables such as the temperature-temperature correlation functions in the Cosmic microwave background (CMB). Hence calculation of inflationary correlators is very important in modern cosmology. In the traditional way of calculating inflationary correlators, or for that matter even correlators for any general field in say de sitter spacetime, one has to do an In-In calculation. This calculation is interaction dependent and can be very long just like calculations of amplitudes in flat space QFTs using Feynmann diagrams. Hence arises the desire or need to bootstrap these correlators. Bootstrapping refers to the idea of not using bulk evolution and instead using certain symmetries or results related to the analytical structure of the correlators to directly obtain the answer. While exploring this field, we would also like to understand concepts related to the analytical structure of correlators, from which one can gain insights into what the initial state (vacua or otherwise) is, as well as some information about the particle content during inflation, which has led to the development of the Cosmological collider physics. One of the most important analytical results in the literature are the soft Limits such as the Maldacena consistency criterion, which provide an important check for our calculations irrespective of the inflation model one considers. While a lot of progress happened in this area in the last approximately 5 years, the bootstrap approach to cosmological correlations is still nascent. Moreover, no method in the current literature can be considered a ``pure" bootstrap since they use bulk information in some way. Motivated by this, we aim to explore the extent of these methods and investigate on how improvements and generalizations can be made.

Total Budget (INR):

34,74,298

Organizations involved