Twist and shout: Gravitomagnetic tidal resonances in binary inspirals


  • Eric Poisson ⋅ CA University of Guelph, Canada


I know, the second part of the title sounds intimidating. Perhaps you're already thinking: this talk is not for me. But resist and come anyway! I promise that I will make the subject accessible to all, and that the physics is actually pretty exciting. What is it about? The context for the talk comes from the ongoing effort to measure gravitational waves from coalescing compact binaries, and to use these observations to learn something about the intimate nature of black holes and neutron stars. Black holes have no internal structure and are therefore boring, but neutron stars are deeply mysterious, featuring matter at densities that far exceed what can be found in ordinary nuclear matter in laboratories. A key to an understanding of their interior comes from the tidal deformation of each neutron star when the binary system is approaching merger, and its imprint on the emitted gravitational waves. I shall describe a less familiar type of tidal field predicted by general relativity, associated with the gravity produced by mass currents (gravitomagnetism). I will show how this tidal field can excite modes of vibration of a rotating neutron star (inertial modes) and produce resonances. The resonances have a large impact on the binary's orbital motion, and this can be measured in the emitted gravitational waves, giving us a new handle on the intimate nature of neutron stars.

About the Speaker

Eric Poisson, University of Guelph, Canada

Eric Poisson earned his bachelor's degree in physics at Laval University in 1987. He received his M.Sc. and Ph.D. degrees in Theoretical Physics from the University of Alberta in 1989 and 1991, respectively. His doctorate thesis is on the internal structure of black holes under the supervision of Werner Israel. He is currently a Full Professor in Department of Physics at the University of Guelph since 1995.



Article ID



Invited Presentations



How to Cite

E Poisson, Twist and shout: Gravitomagnetic tidal resonances in binary inspirals, Proceedings of the Samahang Pisika ng Pilipinas 42, SPP-2024-INV-3A-01 (2024). URL: