SEMINAR 2026
Quasi-Periodic Eruptions and Extreme Mass-Ratio Inspirals:
Bridging Two Windows on Strong-Field Gravity
| Speaker | Dr Lisa Drummond, Caltech, USA |
| Date/Time | Wednesday, 25 Feb, 3pm |
| Location | S11-02-07 Conference Room |
| Host | Asst/Prof Alvin Chua |
Abstract
Quasi-periodic eruptions (QPEs) and gravitational waves from extreme-mass-ratio inspirals (EMRIs) provide complementary electromagnetic and gravitational-wave probes of compact objects orbiting massive black holes. I will first present a timing-based inference framework for QPEs that incorporates secular orbital evolution, including drag from accretion-disk interactions, to constrain black-hole, orbital, and environmental parameters. I will then briefly discuss EMRIs observed with gravitational waves, where orbital dynamics are encoded in waveform phase evolution, and outline how these measurements can be incorporated into hierarchical population inference. Finally, I will propose a joint population-inference framework combining QPEs and EMRIs to reconstruct the demographics of massive black holes and their compact companions using both electromagnetic and gravitational-wave observations.
Biography
Lisa Drummond is a postdoc fellow at Caltech working on a broad range of topics in gravitational and high energy astrophysics related to compact-object binaries as powerful, multi-messenger probes of strong gravity. These include modeling gravitational wave signals from extreme mass-ratio inspirals (EMRIs), uncovering black hole properties through X-ray observations of quasi-periodic eruptions (QPEs), and probing neutron star physics with radio pulsar data. Lisa is particularly interested in the potential of binaries with extreme mass ratios to provide precision tests of general relativity and reveal the fundamental nature of black holes.
