Workshop on Particle Production and Thermal Effects in Inflation

Session

Simulations

6 Feb 2024, 10:00

Virtual @ King's College London

6. Oscillon formation during inflationary preheating with general relativity

Josu Aurrekoetxea (University of Oxford)

06/02/2024, 10:00

In this talk, I describe the use of numerical relativity simulations to study the non-perturbative evolution of inflationary fluctuations during preheating. We find that gravity can enhance the growth of density perturbations, which then collapse and virialize, forming long-lived stable oscillon-like stars. We quantify the compactness of these objects and find that whilst gravitational effects...

7. Lattice simulations during inflation

Angelo Caravano (IAP, Paris)

06/02/2024, 10:50

Inflationary models with significant amplification of small-scale scalar and tensor perturbations have attracted considerable attention in the literature due to their interesting observational signatures, such as primordial black holes and gravitational waves. However, the large enhancement of fluctuations often challenges our perturbative understanding of inflation. I will present a numerical...

8. The strong backreaction in axion inflation: a lattice study

Joanes Lizarraga (University of the Basque Country)

06/02/2024, 11:40

In this talk, I will address the issue of the strong backreaction regime in the abelian axion inflation scenario. I will review our latest work on lattice simulations of the model, where we present a complete framework to simulate this model. Our work demonstrates that inhomogeneities generated during the evolution at the latest stages of inflation are specially relevant to provide a correct...

9. New inflationary probes of axion dark matter

Jiji Fan

06/02/2024, 14:00

The QCD axion, serving as a classical dark matter candidate, has a close intriguing interplay with cosmic inflation, a leading paradigm to understand the origin of our universe. In this talk, I will discuss two novel effects of interaction between the inflaton and the Peccei-Quinn (PQ) scalar field (the phase becomes the axion after symmetry breaking). First, the inclusion of the leading...

10. Lattice Simulations of Gravitational Reheating

Toby Opferkuch

06/02/2024, 14:50

I will present two models for viable gravitational reheating involving a scalar field directly coupled to the Ricci curvature scalar. Crucially to these models are periods of the early Universe where the equation-of-state is stiffer than radiation ($w <1/3$) resulting in tachyonic growth of the scalar fields energy density. In this talk I will detail the phenomenology and delve into scenarios...

16. Future of Cosmological Simulations

Daniel G. Figueroa (Valencia U., IFIC)

06/02/2024, 15:40

This session will be a guided discussion led by Daniel Figueroa. He will start with a visionary talk and introduction to Cosmo-Lattice. Following this, he will engage the audience by posing stimulating questions to stimulate further discussion.