The Dawn of Precision Gravity: From the LHC to LISA

by Prof. Rafael Porto (ICTP-SAIFR, Sao Paulo and DESY, Hamburg)

Monday 29 Oct 2018, 11:45 → 13:30 Europe/Madrid

IFAE Seminar room (IFAE)

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 to shed light on phenomena beyond our current understanding of gravity and particle physics. In principle, the non-perturbative 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 offers a unique opportunity to study physics beyond the Standard Model through GW precision data (GWPD). Yet, the associated computational challenges are enormous. While current GW templates for compact binary sources may be sufficient for detection and crude parameter estimation, they are still too coarse for precision physics. We then find ourselves in a situation similar to particle physics in the pre-LHC era: for key processes within empirical reach theoretical uncertainties may dominate. To move forward, and profit the most from GW observations, more accurate waveforms will be needed. The "effective field theory" approach to the binary inspiral problem in general relativity — which my collaborators and I have developed using tools that originated in particle physics — has been instrumental for the construction of the state-of-the-art GW template bank. In this talk I will review how these novel techniques will provide the building blocks that will enable foundational investigations in physics through GWPD: from probes of dynamical spacetime and strongly interacting matter, to the potential to discover exotic compact objects and ultra-light particles in nature. To conclude I will discuss the theoretical challenges ahead, in modeling the binary’s dynamics, to maximize the discovery potential of GW observations in a new era of explorations of the cosmos.