The 35th Midwest Relativity Meeting & Eric Fest

Session

Saturday Morning Session 1

1 Nov 2025, 09:00

113 (MacKinnon Building)

49. The Entropy of Dynamical Black Holes and Apparent Horizons

Victor Zhang

01/11/2025, 09:00

We previously proposed a new formula for the entropy of a dynamical black hole (valid to leading order for perturbations off of a stationary black hole background) in an arbitrary classical diffeomorphism covariant Lagrangian theory of gravity in 𝑛 dimensions. Our formula in general relativity gives the entropy of a dynamical black hole as its area minus an integral involving the expansion of...

17. Causality and instability of the relativistic hydrodynamics from holography

Alex Buchel (UWO)

01/11/2025, 09:15

We use holography as a tool to explore all-order in velocity gradients relativistic hydrodynamics. We demonstrate the link between causality and instability of the theory.

45. Sourced Carrollian Fluids Dual to Black Hole Horizons

Sercan Hüsnügil (Perimeter Institute)

01/11/2025, 09:30

The (degenerate) geometry of event horizons is linked to Carrollian fluids. We investigate the behaviour of event horizons via a perturbative coupling to a massless scalar field, making connections to Carrollian hydrodynamics with a driving source, and discuss the fluid equilibration in tandem with the horizon’s relaxation to equilibrium. We observe that after the perturbation dies off, the...

54. Guesswork in the gap: the impact of uncertainty in the compact binary population on source classification

Mr Utkarsh Mali (CITA (Canadian Institute for Theoretical Astrophysics))

01/11/2025, 09:45

The nature of the compact objects within the supposed 3-5M⊙ “lower mass gap” remains uncertain. Observations of GW190814 and GW230529 highlight the challenges gravitational waves face in distinguishing neutron stars from black holes. Interpreting these systems is especially difficult because classifications depend simultaneously on measurement noise, compact binary population models, and...

58. Impact of nonlinearities on relativistic dynamical tides in compact binary inspirals

Tristan Pitre (University of Guelph)

01/11/2025, 10:00

30. Scalar field perturbation of a rotating wormhole to obtain quasi-normal modes.

Ramesh Radhakrishnan (Baylor University)

01/11/2025, 10:15

In this era of gravitational waves from blackhole and neutron star mergers, GW data is being collected at an amazing pace. There is a possibility of GWs of BH mergers scattering from wormholes and/or other exotic compact objects (ECOs), if they exist. Specialized groups are searching for wormhole signatures. We share the results of our study of scalar field perturbations and quasi-normal modes...