Cosmology WG meeting, GdR Gravitational Waves

mercredi 13 nov. 2019, 09:30 → 18:00 Europe/Paris

Amphitheatre Pierre Gilles de Gennes (APC Paris)

09:30 → 10:30 Gravitational waves from phase transitions

I will review the current understanding of how phase transitions in the early Universe generate gravitational waves, and
their prospects for observation at LISA.

Orateur: Prof. Hindmarsh Mark (Sussex U. & Helsinki U)

10:40 → 11:00 coffee break

11:00 → 12:00 Primordial Black Holes and Gravitational Waves

We will discuss some aspects of primordial black holes, such as how they may form in the early universe, why they may compose all the dark matter, and how LISA will be able to detect the associated gravitational waves.

Orateur: Prof. Riotto Antonio (Geneva University)

12:15 → 13:45 lunch break

13:45 → 14:45 New insights on cosmic strings

Orateur: Prof. Ringeval Christophe (Louvain University)

15:00 → 15:30 Stochastic Gravitational Wave Background

Orateur: Dr Irina Dvorkin (IAP)

15:45 → 16:15 The road to precision cosmology with gravitational waves and ground based detectors.

Orateur: Dr Simone mastrogiovanni (APC)

16:30 → 17:00 Kerr Primordial Black Holes: Towards New Constraints

The primordial black holes solution to the dark matter issue has lately received much attention due to the
non-detection of dark matter particles (WIMPs or axions) in both direct and indirect channels. These
black holes are expected to form at the very beginning of the Universe through the collapse of primordial
density fluctuations. Depending on their mass distribution, they can have several observable consequences,
thus allowing to set constraints on their density -- and the fraction of dark matter they can represent.
The observations range from gravitational micro and femto-lensing to the emission of energetic particles
through Hawking radiation. In this seminar, we will focus on the Hawking radiation constraints by extending
them from the Schwarzschild primordial black holes (non-rotating) to the Kerr metric (rotating black holes)
and from monochromatic mass distributions to extended ones. This work is based on the new public code BlackHawk
that computes the Hawking spectra of Schwarzschild/Kerr black holes and that will be briefly presented.

Short abstract:

In this talk we will discuss new constraints on primordial black holes and the fraction of dark matter they can represent,
based on the computation of the Hawking radiation emitted by extended mass functions of Kerr (rotating) holes.

Orateur: M. Jérémy Auffinger (IPNL Lyon)