PIRSA:15110064

Probing Fundamental Physics with Universal Relations for Neutron Stars

Yagi, K. (2015). Probing Fundamental Physics with Universal Relations for Neutron Stars. Perimeter Institute. https://pirsa.org/15110064

Yagi, Kent. Probing Fundamental Physics with Universal Relations for Neutron Stars. Perimeter Institute, Nov. 19, 2015, https://pirsa.org/15110064 

          @misc{ pirsa_PIRSA:15110064,
            doi = {10.48660/15110064},
            url = {https://pirsa.org/15110064},
            author = {Yagi, Kent},
            keywords = {Strong Gravity},
            language = {en},
            title = {Probing Fundamental Physics with Universal Relations for Neutron Stars},
            publisher = {Perimeter Institute},
            year = {2015},
            month = {nov},
            note = {PIRSA:15110064 see, \url{https://pirsa.org}}
          }

Kent Yagi University of Virginia

DOI 10.48660/15110064
Collection
Talk Type Scientific Series
Subject

Abstract

Neutron stars offer us an excellent testbed to probe fundamental physics, such as nuclear physics and strong-field gravity. Unlike the well-studied mass-radius relation for neutron stars that depends strongly on their internal structure, I first report unexpected universal relations that we found among the moment of inertia, tidal Love number and quadrupole moment ("I-Love-Q" relations) that are insensitive to the internal structure. Such universal relations help us break the degeneracy among neutron star parameters when probing fundamental physics with radio, X-ray or gravitational wave observations. In the second part of my talk, I explain similar universal relations among neutron star multipole moments, which resemble the no-hair property of black holes. I also mention how one can increase the amount of universality, and discuss that the transition from a "follicly-challenged" neutron star to a "bald" black hole may be related to second order phase transitions in condensed matter physics. In the final part of my talk, I report yet another universal relations among tidal parameters in gravitational waves from neutron star binaries. Such relations allow us to improve the measurability of the tidal effect with future observations, which increases the ability of probing astrophysics, nuclear physics, gravitational physics and even cosmology.