In this talk I’ll discuss two recent results on BH superradiance: first, I will describe how BH photon superradiance is typically quenched by interactions of the photon cloud with the ambient electrons. Second, I will explain how an axionic cloud may impact the CMB if it decays into low energy photons which quickly heat and ionise the surrounding medium to Mpc scales.

The gravitation group is inviting you to the following seminar:

Speaker

Alberto Mangiagli, APC Paris

The astrophysics of black hole binaries in the era of gravitational wave astronomy

The NANOGrav Collaboration has recently reported strong evidence for a stochastic common-spectrum process, which we interpret as a SGWB in the framework of cosmic strings. The possible NANOGrav signal would correspond to a string tension Gμ∈(4×10^{−11},10^{−10}) at the 68% confidence level, with a different frequency dependence from supermassive black hole mergers.

The gravitation group is inviting you to the following seminar:

A flexible model for neutron star equation of state from nuclear physics

Development in multi-messenger astronomy over the last few years has
opened new facets to the hadronic matter at densities beyond our terrestrial
reach. It provides new constraints to the theories of nuclear physics, where an
absolute energy density functional is desired from ab-initio mechanisms. Under
the realm of general relativity, there is a one-to-one correspondence between

The emergence of the three-dimensional structure of the cosmic web over
the history of the Universe displays very distinctive features when
observed in X-rays, where both the most massive collapsed structure
(clusters of galaxies) and the most energetic events in the life of
galaxies (AGN and Quasars) reveal themselves unambiguously. The next
generation of wide-area, sensitive X-ray surveys designed to map the hot
and energetic Universe will be heralded by eROSITA (extended ROentgen
Survey with an Imaging Telescope Array), the core instrument on the

We are organising a cycle of seminars of philosophy of science at APC.
During 30 min, philosophers will present their research on a topic related to the themes of research of the laboratory. The presentation will be folllowed by a 30-min discussion between the audience and the speaker.
The event is open to all APC members, external members can attend on request.
A zoom link is communicated by email for the ones who wish to attend remotely.