19–21 Aug 2024
Lundbeck Auditorium
Europe/Copenhagen timezone

Bayesian Model Selection of Inflationary Models Using the CONNECT Emulation Framework

20 Aug 2024, 13:35
20m
Lundbeck Auditorium

Lundbeck Auditorium

Plenary Parallel

Speaker

Camilla Theresia Grøn Sørensen (Department of Physics and Astronomy, Aarhus University)

Description

Bayesian model selection is an invaluable tool when comparing different inflationary models. This is done by computing the Bayesian evidence for the different models using nested sampling, and then comparing them using the Bayes factor. Computing the Bayesian evidence of a model using an Einstein-Boltzmann solver code takes weeks, if not months for complex models, and it is therefore very rarely done. Using a neural network, e.g. from the CONNECT framework, to emulate cosmological observables, the time used to compute the Bayesian evidence of a model can be brought down from tens of thousands of CPU hours to about 100 CPU hours.
In this talk, I will present the setup and programs used to compute the Bayesian evidence using the neural network framework CONNECT. I will also show the Bayesian evidence for the cosmological model ΛCDM+ɑ_s+r computed with CLASS and CONNECT respectively. Furthermore, I will also present a comparison of different inflationary models using the Bayes factor.

Primary author

Camilla Theresia Grøn Sørensen (Department of Physics and Astronomy, Aarhus University)

Co-authors

Andreas Nygaard (Aarhus University) Steen Hannestad (Aarhus University)

Presentation materials