Simon Fraser University
SFU Cosmology Seminars

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Tuesday, 19 May 2020, 12:00 in Zoom

Dr. José Tomas Gálvez Ghersi (University of Mississippi)

Numerical renormalization group-based approach to secular perturbation theory

The standard methods of perturbative analysis are crucial to revealing many features of a physical system when it is not viable to obtain exact solutions. Nevertheless, the use of a truncated expansion might generate diverging solutions in systems that are known to be bound. Following the perspective of secular perturbation theory, we propose the numerical implementation of a renormalization group-based approach to promote the background parameters into time-dependent quantities. These new quantities are not restricted only to avoid secular growth, but can also improve the accuracy of the solution. As a concrete example, we use this method to calculate the soliton-like solutions of the Korteweg-de Vries equation deformed by adding a small damping term. This example shares several features with the evaluation of gravitational waveforms modified by perturbative corrections of general relativity.

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