Events on Wednesday, January 23rd, 2019
- Department Meeting
- Time: 12:15 pm - 1:30 pm
- Place: 5310 Chamberlin Hall
- Speaker: Sridhara Dasu, UW-Madison
- Host: Sridhara Dasu
- Dept of Philosophy Job Talk
- STRUCTURE AND EQUIVALENCE IN YANG-MILLS THEORY
- Time: 4:00 pm
- Place: Memorial Union, Old Madison Room
- Speaker: Sarita Rosenstock University of California, Irvine, University of California, Irvine Department of Logic and Philosophy of Science
- Abstract: Scientists and philosophers often invoke
parsimony as a theoretical virtue alongside
descriptive accuracy, and aim to minimize the
amount of structure present in mathematical
formalisms used to represent physical systems. I
present a proposal for formalizing structure
comparison in physics using category theory,
which can be thought of as the mathematical
theory of structure. I show how this method can
be used to compare alternative formulations of
Yang-Mills theory (which underlies modern
particle physics), and evaluate claims by
philosophers and physicists regarding their
relative structure.
- Whitord Public Talk Astronomy
- Einstein's Waves: Cosmic Sounds from Black Holes and Neutron Stars
- Time: 5:30 pm - 7:00 pm
- Place: 2241 Chamberlin Hall
- Speaker: Vicky Kalogera, Northwestern University
- Abstract: For the first time, scientists have observed ripples in the fabric of spacetime called gravitational waves, arriving at the earth from cataclysmic events in the distant universe. These recent observations confirm a major prediction of Albert Einstein’s 1915 general theory of relativity and open an unprecedented new window onto the cosmos. Gravitational waves carry unique information about their dramatic origins and about the nature of gravity that cannot otherwise be obtained. Detected gravitational waves were produced during the final fraction of a second of the mergers of two black holes but also during the last hundred seconds of the collision of two neutron stars. The latter is the first ever cosmic event to be observed both in gravitational waves and in electromagnetic waves, shedding light to several longstanding puzzles, like the production of gold in nature and the physics origins of brief gamma-ray flashes. I will review the beginnings of this exciting field of cosmic exploration and the unprecedented technology and engineering that made it possible.
- Host: Prof Robert Mathieu