Microscopic Probes of Inflationary Cosmology

Project Information

INFPROBES

Grant agreement ID: 751778

DOI

10.3030/751778

Project closed

EC signature date 22 March 2017

Start date 1 October 2017

End date 30 September 2019

Funded under

• EXCELLENT SCIENCE - Marie Skłodowska-Curie Actions

Total cost

€ 177 598,80

EU contribution

€ 177 598,80

Coordinated by

UNIVERSITEIT VAN AMSTERDAM
Netherlands

Periodic Reporting for period 1 - INFPROBES (Microscopic Probes of Inflationary Cosmology)

Reporting period: 2017-10-01 to 2019-09-30

Summary of the context and overall objectives of the project

"This project concerns the understanding of the initial conditions of our universe. The universe began its existence in a state of very high temperature and certain constituents. However, instead of having random initial conditions, it had highly correlated initial seeds, which are responsible for the later formation of all structure that we see today. The appearance of those seeds is naturally explained by a period of very accelerated expansion in the earliest stage of the universe. This project investigated this period - so called ""inflation"" - and developed various new tools designed to better understand said period, and also to potentially verify it in detail, through future observations of the sky.

Although of theoretical nature, this project touches a deep question that is widely appreciated by society - what is the origin of the universe, and why is there any organized structure in it."

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

This project produced a new set of tools to understand the physics of inflation. Its main result so far has been to make the connection between early universe physics and particle physics very sharp. I developed a formalism that connects, quantitatively, the study of particle collisions in detectors on earth - like the LHC at CERN - to the physics of inflationary cosmology. Given the advance of methods and results in particle physics, this connection will provide us many new, deep insights into the formation of primordial seeds in the universe.

In more detail, I produced a new set of templates of primordial correlations that can only be explained by inflationary cosmology. This menu, under certain technical assumptions, is unique. Thus, seeing these correlations in the sky would give us very strong evidence for the existence of an early inflationary era. It would also tell us about the existence of new particles and forces, perhaps inaccessible by current particle physics detectors. The figure of this project shows an example of such a non-trivial correlation, which would only be sourced by an (otherwise unobservable) new particle.

I have also produced a new set of tools to calculate what happens during inflation, adapting standard tools of particle physics. A key difference between particle physics and cosmology is the non-trivial time evolution of the universe, unlike the static nature of particle physics. The tools I derived were adapted from the framework of particle physics to the setting of cosmology.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

"The connection between particle physics and cosmology, in the ""Cosmological Bootstrap"" program, has many potential impacts in theoretical physics. It is a novel approach that sheds new light on the nature of time in the early universe, and builds a quantitative connection to a different area of physics."

A new particle creates a correlation between the primordial seeds of the universe.