Simon Fraser University
SFU Cosmology Seminars

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Tuesday, 28 July 2020, 12:00 in Zoom

Dr. José Tomas Gálvez Ghersi (University of Mississippi)

A fixed point for black hole distributions

Understanding distributions of black holes is crucial to both astrophysics and quantum gravity. Studying astrophysical population statistics has even been suggested as a channel to constrain black hole formation from the quantum vacuum. Here we propose a Gedankenexperiment to show that the non-linear properties of binary mergers (simulated with accurate surrogate models) generate an attractor in the space of distributions. Our results show that the joint distribution of spin magnitude and fractional mass loss evolves to a fixed point, converging in a few generations. The features of this fixed point distribution do not depend on the choice of initial distribution. Since a black hole merger is irreversible it produces entropy - possibly the largest source of entropy in the universe. The fixed-point distributions are neither isothermal nor isentropic, and initially thermodynamic states evolve away from thermality. We finally evaluate the specific entropy production rate per merger from initially thermal and non-thermal distributions, which converges to a constant.

Seminars in 2019:

2019-09-10 14:30 in P8445B - Gabor Kunstatter (University of Winnipeg/SFU): What can quantum gravity tell us about the beginning and end of time?
2019-09-17 14:30 in P8445B - Andrei Frolov (SFU): Dust is everywhere
2019-10-08 14:30 in P8445B - Douglas Scott (UBC): Evaporating evidence for Hawking points
2019-10-22 14:30 in P8445B - Arif Babul (UVic): Cosmology with galaxy clusters
2019-11-19 14:30 in P8445B - Richard Shaw (UBC): Probing Dark Energy with CHIME
2019-11-26 14:30 in P8445B - Joanna Woo (SFU): Primer on machine learning for astronomy
2019-12-03 14:30 in P8445B - Ludovic Van Waerbeke (UBC): Axion Quark Nuggets: a candidate for baryonic, cold and strongly interacting dark matter
2020-01-20 15:00 in P8445B - Francesc Ferrer (Washington University): Gravitational wave signals of early universe axion dynamics
2020-02-14 14:30 in C9000 - Katie Mack (North Carolina State University): Dark matter: a cosmological perspective (physics colloquium)
2020-02-26 14:30 in P8445B - Paul Wiegert (University of Western Ontario): Interstellar asteroids and comets: what are they and where do they come from?
2020-02-28 14:30 in C9000 - Sara Ellison (University of Victoria): Clash of the Titans: Galaxy mergers in the nearby Universe (physics colloquium)
2020-05-12 12:00 in Zoom - Levon Pogosian (SFU): Relieving the Hubble tension with primordial magnetic fields
2020-05-19 12:00 in Zoom - José Tomas Gálvez Ghersi (University of Mississippi): Numerical renormalization group-based approach to secular perturbation theory
2020-06-02 12:00 in Zoom - Leo Stein (University of Mississippi): Gravitational-wave tests of GR with simulations of beyond-GR theories
2020-06-16 12:00 in Zoom - Andrei Frolov (Simon Fraser Univeristy): Primordial non-Gaussianity from preheating
2020-07-02 14:30 in Zoom - Jack Gegenberg (University of New Brunswick): Collapse of a rotating shell in 3+1 dimensions (special seminar)
2020-07-07 12:00 in Zoom - Joanna Woo (Simon Fraser Univeristy): Machine learning as a tool for astrophysics
2020-07-28 12:00 in Zoom - José Tomas Gálvez Ghersi (University of Mississippi): A fixed point for black hole distributions

[ See complete seminar archives | iCal feed ]

Modified by Andrei Frolov <frolov@sfu.ca> on 2023-11-01