New Horizons in Primordial Black Hole physics (NEHOP)

Session

Session 2

19 Jun 2023, 11:40

Naples, Italy

Conveners

Session 2

• Chair: Sukannya Bhattacharya

20. Primordial black holes and how to (not over-) produce them

Pippa Cole

19/06/2023, 11:40

Talk

The simplest way to produce primordial black holes is via the collapse of large overdense regions in the early universe. However, a boost of the primordial perturbations requires very specific dynamics in single-field inflation, and both the amplitude of perturbations and the resulting abundance of primordial black holes are extremely sensitive to the parameters of the inflationary model. I...

15. Statistics of coarse-grained cosmological fields in stochastic inflation

Yuichiro Tada (Nagoya University)

19/06/2023, 12:00

Talk

We present a generic framework to compute the one-point statistics of cosmological perturbations, when coarse-grained at an arbitrary scale $R$, in the presence of quantum diffusion. Making use of the stochastic-$\delta N$ formalism, we show how it can be related to the statistics of the amount of expansion realised until the scale $R$ crosses out the Hubble radius. This leads us to explicit...

30. Stochastic constant-roll inflation and primordial black holes

Dr Eemeli Tomberg (NICPB Tallinn)

19/06/2023, 12:20

Talk

Primordial black holes can be seeded by perturbations from cosmic inflation. In the literature, these perturbations are often computed in linear order so that their statistics are Gaussian. However, non-Gaussianities can be important for the rare events of black hole formation. The leading non-Gaussianities can be computed with the non-linear formalism of stochastic inflation, which predicts...