Series: The London Relativity and Cosmology Seminar
Speaker: Johannes Noller (Oxford)
Abstract: Theories with multiple spin-2 fields, or 'metrics', have recently gathered a lot of attention. In this talk I hope to show what makes these theories interesting and in the process present the recently constructed effective field theory for interacting spin-2 fields, showing how generic ghost-free massive and 'multi-gravity' theories can be constructed (also encompassing dRGT massive gravity and Hassan-Rosen bigravity). In particular I will highlight several intriguing features of such theories, such as the emergence of a generalised Fierz-Pauli tuning, their decoupling limit phenomenology and the possibility of tuning strong coupling scales.