Charlie Hoy and Lasse Schmieding win best student talk prizes at Britgrav 2019

We are delighted to award Charlie Hoy and Lasse Schmieding the CQG-sponsored best student talk prize, for their talks at the recent Britgrav 2019 conference, held at Durham University.

BritGrav (British Gravity Meeting) is an annual conference, based in the United Kingdom and Ireland, which covers the full range of gravitational physics. A particular aim of the meeting is to give graduate students and postdocs the opportunity to present their work. Classical and Quantum Gravity is the long-standing sponsor of the conference.

Britgrav19 winners

Charlie Hoy (left) and Lasse Schmieding

The judging panel* remarked on the particularly high standard of talks at this year’s meeting, and after much deliberation decided to give a joint award. Please see below for details of the winning talks.

The winners will each receive from CQG a £50 Amazon voucher and certificate. Congratulations again to Charlie and Lasse!

Ben Sheard, CQG Publisher

*Judging Panel:
Dr. Timothy Clifton, Queen Mary University of London
Prof. Atsushi Higushi, University of York
Dr. Baojiu Li, Durham University
Dr. Alex Peach, Durham University
Prof. Elizabeth Winstanley, University of Sheffield

Details of winning talks:

Charlie Hoy, Cardiff University
PhD supervisors: Professor Stephen Fairhurst and Professor Mark Hannam

Title of talk: Exploring the measurability of precession

Abstract: For binary black hole coalescences with spins misaligned with the total orbital angular momentum, the orbital plane of the binary precesses around the approximately constant total angular momentum, leaving behind characteristic modulations in the detected gravitational waveform. Despite comprehensive models for this phenomenon, there has been no evidence for precession in any of the current detections to date [1]. It is not immediately clear from the waveform models and the current LIGO detector network when precession will be measurable. We present a new, intuitive model for understanding the observability of precession [2][3]. We demonstrate the accuracy of this model by comparing the predictions to a systematic parameter estimation study across the parameter space [4]. Using this model, we can calculate the fraction of binaries for which precession is measurable and predict when precessional effects will be observed for the first time [3].

[1] LIGO Scientific Collaboration, Virgo Collaboration. GWTC-1: a gravitational-wave transient catalog of compact binary mergers observed by LIGO and Virgo during the first and second observing runs. arXiv preprint arXiv:1811.12907. 2018 Nov 30.
[2] Fairhurst et al. (in preparation)
[3] Fairhurst et al. (in preparation)
[4] Green at al. (in preparation)

Lasse Schmieding, University of York
PhD supervisor: Professor Atsushi Higuchi

Title of talk: Quantum linearisation instability conditions in supergravity on a 3-Torus

Abstract: When one studies the linear perturbations around a solution to Einstein’s equations which admits compact Cauchy surfaces and Killing symmetries, then it is known that one must impose certain quadratic linearisation stability constraints to obtain physically plausible perturbations. The constraints amount to asking that the generators of the symmetries vanish. Implementing these constraints in a quantum theory can make the construction of a physical Hilbert space more complicated, as they ask that all physical states be invariant under the background symmetries. In the work presented, we considered a simple supergravitational system on a 3-torus, where the vanishing of the supercharge arises as an additional linearisation constraint in the linearised theory and we implemented a procedure to construct an appropriate physical Hilbert space for the quantum version of the linearised theory.