CosmoFONDUE - Cosmological Fundamental Observables and Novel Discoveries in Universe Evolution

Session

GWs emitted before the CMB

2B

11 Jun 2025, 11:30

Main auditorium (École de physique, Quai Ernest-Ansermet 24, 1205 Genève, Suisse)

82. Introduction to gravitational wave probes of the early Universe

Daniel Figueroa

11/06/2025, 11:30

GWs emitted before the CMB

talk

72. Using Deep Learning to disentangle the cosmological and astrophysical Stochastic Gravitational Wave Backgrounds

Mr Bill Atkins (Swansea University), Matthew Di Ferrante (Independent Researcher)

11/06/2025, 12:00

GWs emitted before the CMB

talk

We apply a Convolutional Neural Network (CNN) to Pulsar Timing Array residuals to identify the cosmological contribution to the Stochastic Gravitational wave Background for a variety of different cosmological models.

We find the CNN can accurately identify the cosmological contributions, and reconstruct injected signals with at least as much success as current Bayesian methods, but with...

55. Gravitational waves detection from PTA and Astrometry

Nayeli Marisol Jimenez Cruz (Swansea University)

11/06/2025, 12:20

talk

Pulsar Timing Array (PTA) observations provide strong evidence for a stochastic gravitational wave background (SGWB), potentially originating from astrophysical sources or early universe phenomena. If the SGWB is cosmological, our relative motion with respect to the SGWB rest frame induces a kinematic anisotropy, which could dominate over intrinsic anisotropies, similar to the cosmic microwave...

22. Gravitational waves from phase transitions

Alberto Roper Pol (University of Geneva)

11/06/2025, 12:40

GWs emitted before the CMB

talk

Gravitational waves (GWs) can be produced by a first-order phase transition in the early Universe via the fluid perturbations induced in the primordial plasma by the expansion and collision of broken-phase bubbles. I will review the production of GWs by the anisotropic stresses of velocity and magnetic fields induced in a first-order phase transition and present analytical estimates and...

32. The imprints of Primordial Gravitational Waves on the Large Scale Structure

Mariam Tarek Mohamed Abdelaziz (Scuola Superiore Meridionale)

GWs emitted before the CMB

talk

Primordial Gravitational Waves (PGWs) are a key prediction of inflation, and efforts are ongoing to detect them through CMB polarization patterns and direct interferometric detection. In this talk, I will present a novel approach to probing PGWs through their impact on Large-Scale Structure.
PGWs are often assumed to have a negligible effect on structure formation, but in our study, we show...