16.05.2018 / 14:30 - 15:30 / Hamburg, seminar room 2, bldg. 2a

Theory Colloquium

Gravitational Collider Physics

Rafael Porto (DESY)

It is indisputable that gravitational wave (GW) science will play a transformative role in astrophysics. It is, however, less clear what impact GW measurements will have on other branches of physics, and in particular whether they can shed light on phenomena beyond the Standard Model. In principle, the non perturbative gravitational regime in the dynamics of binary systems may carry the imprint of 'new physics'. However, the need for numerical modeling, together with the small number of cycles involved, may hinder our ability to pinpoint different scenarios, if restricted only to the merger phase. In contrast, an accurate analytic reconstruction of the signal during the inspiral, in combination with simulations for the late stages of the coalescence, offers a unique opportunity to study physics beyond the Standard Model through GW observations. A notable example — motivated by solutions to known puzzles such as dark matter and the strong CP problem — are 'ultralight’ particles. The required weak coupling makes detecting these particles by traditional experimental means extremely challenging. At the same time, their large Compton wavelengths means that, if present in nature, they will be efficiently produced by superradiance instabilities in rapidly rotating black holes. In this talk, I will discuss how the presence of a boson cloud in a binary system can be revealed in the GW signals, both from the cloud itself and that of the two-body inspiral. Remarkably, the presence of a binary companion leads to the existence of resonant transitions, between growing and decaying modes of the cloud, which produces a sharp time-dependent feature, for instance, in the contribution from finite-size terms in the waveforms. The observation of these effects would constrain the properties of putative ultralight bosons in nature through precision GW data, offering new probes of physics beyond the Standard Model with present and future GW detectors.

More Information: https://indico.desy.de/indico/event/19875/