Department of Mathematical Sciences
University of Liverpool
Liverpool L69 7ZL
+44 151 794 3778 (Office)
+44 7568 168895 (Mobile)
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Curriculum Vitae (last modified 22 July 2021)
I am a Lecturer in theoretical physics at the University of Liverpool, and a UK Research & Innovation (UKRI) Future Leader Fellow. I previously held postdoctoral research positions at the University of Bern, Syracuse University and the University of Colorado Boulder after studying at Amherst College and completing my PhD at Boston University. For shorter periods I have worked at the International Centre for Theoretical Sciences, Bangalore; the Kavli Institute for Theoretical Physics, Santa Barbara; the Humboldt University of Berlin; the Aspen Center for Physics; the National Center for Theoretical Sciences, Taipei; Lawrence Livermore National Lab; and CERN, the European Organization for Nuclear Research. In addition to these institutions I have been supported by the US Department of Energy, the US National Science Foundation, the National Science Council of Taiwan, and the UK Science and Technology Facilities Council.
Research [complete overview, GitHub]
I use computing to gain insight into strongly interacting quantum field theories, primarily in the context of high-energy particle physics. I employ lattice field theory, a non-perturbative framework that enables first-principles investigations of strongly coupled systems. Making use of lattice regularization as a broadly applicable tool, I address questions that are important both theoretically and phenomenologically, within and beyond the standard model of particle physics.
My work currently focuses on composite dark matter, composite Higgs models, supersymmetric lattice field theories, and lattice field theories that suffer from so-called sign problems. Postdoctoral researcher Chris Culver is working with me to help develop quantum simulation for lattice field theory, funded by the UKRI project New Frontiers of Lattice Field Theory.
A central aspect of my research is the development and deployment of software for high-performance parallel computing. I do the bulk of my code development publicly through GitHub, and whenever possible I release my programs under open-source free software licenses such as the GNU General Public License.
In order both to contribute to public engagement with science and to recognize taxpayer support of my work over the years, I write non-technical (or at least less-technical) descriptions of my research projects for interested non-experts. Experts can find my recent publications below.
I am currently supervising two PhD students. Felix Springer is using density-of-states methods to research first-order phase transitions connected to composite dark matter and gravitational waves. Angel Sherletov is researching supersymmetric lattice field theories, focusing on numerical analyses of lower-dimensional supersymmetric QCD.
While I have no further PhD positions available at present, I am available to supervise undergraduate and MSc projects in theoretical physics. Information on the corresponding project modules is available through the maths intranet (login required). I can suggest a few possible topics for projects, some of which should eventually appear on the intranet as well.
Teaching [complete list]
At Liverpool I most recently taught third-year undergraduate Statistical Physics (MATH327) in spring 2021. Although online resources for this module are organized through the University's Virtual Learning Environment, some can be found here. Due to remote teaching arranged to mitigate the Covid-19 pandemic, these resources are significantly different from those for the spring 2020 version of the module.
Elsewhere I recently taught Lattice Field Theory Algorithms at the 2021 Bad Honnef Physics School. Previous teaching includes a postgraduate course on New strong dynamics beyond the standard model, at the University of Bern, as well as informal courses on Advanced quantum field theory at the University of Colorado and at Syracuse University. Some of the online resources for these courses, in particular solutions to textbook exercises, are password protected.
Recent publications and preprints [complete list, INSPIRE, ORCID, arXiv, Google]
Refereed journal articles
Goldstone Boson Scattering with a Light Composite Scalar
LSD Collaboration: Thomas Appelquist, Richard C. Brower, Kimmy K. Cushman, George T. Fleming, Andrew Gasbarro, Anna Hasenfratz, James Ingoldby, Xiao-Yong Jin, Joe Kiskis, Ethan T. Neil, James C. Osborn, Claudio Rebbi, Enrico Rinaldi, David Schaich, Pavlos Vranas, Evan Weinberg and Oliver Witzel
Submitted to Physical Review D (2021) [arXiv:2106.13534, INSPIRE]
Stealth dark matter confinement transition and gravitational waves
LSD Collaboration: Richard C. Brower, Kimmy Cushman, George T. Fleming, Andrew Gasbarro, Anna Hasenfratz, Xiao-Yong Jin, Graham D. Kribs, Ethan T. Neil, James C. Osborn, Claudio Rebbi, Enrico Rinaldi, David Schaich, Pavlos Vranas and Oliver Witzel
Physical Review D 103:014505 (2021) [arXiv:2006.16429, INSPIRE]
Data release at doi:10.5281/zenodo.3921870
Near-conformal dynamics in a chirally broken system
LSD Collaboration: Thomas Appelquist, Richard C. Brower, Kimmy K. Cushman, George T. Fleming, Andrew D. Gasbarro, Anna Hasenfratz, Xiao-Yong Jin, Ethan T. Neil, James C. Osborn, Claudio Rebbi, Enrico Rinaldi, David Schaich, Pavlos Vranas and Oliver Witzel
Physical Review D 103:014504 (2021) [arXiv:2007.01810, INSPIRE]
Three-dimensional super-Yang–Mills theory on the lattice and dual black branes
Simon Catterall, Raghav G. Jha, David Schaich and Toby Wiseman
Physical Review D 102:106009 (2020) [arXiv:2010.00026, INSPIRE]
Data release at doi:10.5281/zenodo.4059476
Nonpeturbative investigations of SU(3) gauge theory with eight dynamical flavors
LSD Collaboration: Thomas Appelquist, Richard C. Brower, George T. Fleming, Andrew Gasbarro, Anna Hasenfratz, Xiao-Yong Jin, Ethan T. Neil, James C. Osborn, Claudio Rebbi, Enrico Rinaldi, David Schaich, Pavlos Vranas, Evan Weinberg and Oliver Witzel
Physical Review D 99:014509 (2019) [arXiv:1807.08411, INSPIRE]
Linear Sigma EFT for Nearly Conformal Gauge Theories
LSD Collaboration: Thomas Appelquist, Richard C. Brower, George T. Fleming, Andrew Gasbarro, Anna Hasenfratz, James Ingoldby, Joe Kiskis, James C. Osborn, Claudio Rebbi, Enrico Rinaldi, David Schaich, Pavlos Vranas, Evan Weinberg and Oliver Witzel
Physical Review D 98:114510 (2018, Editors' Suggestion) [arXiv:1809.02624, INSPIRE]
Recent presentations [complete list, map]
Lattice studies of supersymmetric Yang--Mills in 2+1 dimensions, Workshop on Relativistic Fermions in Flatland, ECT* Trento, 9 July 2021 [recording]
Lattice strong dynamics for composite Higgs sectors, Swansea University Theory Seminar, 11 June 2021
Broader applications of lattice field theory, UK Lattice Field Theory Virtual Centre kick-off event, 24 March 2021
Progress and prospects of lattice supersymmetry, Program on Nonperturbative and Numerical Approaches to Quantum Gravity, String Theory and Holography, International Centre for Theoretical Sciences, Bangalore, 18 January 2021 [recording]
Lattice studies of maximally supersymmetric Yang–Mills theories, Perimeter Institute Quantum Fields and Strings Seminar, 10 January 2020
Lattice field theory for composite dark matter, University of Southampton High Energy Theory Seminar, 29 November 2019
Maximally supersymmetric Yang–Mills on the lattice, University of Southampton String Theory Seminar, 27 November 2019
Supersymmetric lattice field theories: Classical simulations and quantum opportunities, Workshop on High-energy Physics at Ultra-cold Temperatures, ECT* Trento, 12 June 2019
Lattice studies of maximally supersymmetric Yang–Mills theories, University of Liverpool Theoretical Physics Seminar, 28 November 2018
Stealth dark matter and gravitational waves, Lattice 2019, Wuhan, China, 19 June 2019
Lower-dimensional lattice supersymmetry, University of Bern AEC Institute for Theoretical Physics lunch seminar, 22 March 2018
Phases of a strongly coupled four-fermion theory, Lattice 2017, Granada, Spain, 22 June 2017
Last modified 21 September 2021