Dr Matthew Buican

Profile

I am a theoretical physicist. I received my AB in Physics from Harvard University and my PhD in Physics from Princeton University. I was a postdoc at CERN, Rutgers University, and The University of Chicago before joining the faculty at QMUL.

Teaching

In 2017-18, I created a course called "Supersymmetric Methods in Theoretical Physics" (see here). I've taught it every year since.

The basic idea is to give a course in supersymmetry that emphasizes the simplest settings in which general principles emerge rather than studying SUSY as an extension of the Standard Model (although this topic is interesting in its own right!). Some of the areas to be covered include the Witten index, N=2 SUSY quantum mechanics (SQM), N=(2,2) SQM, and various applications (e.g., to understanding dynamics of quantum mechanical systems, Berry phase, etc.). The last part of the module will cover 3D SUSY theories and some of the remarkable dualities that emerge.

I have also supervised more than a dozen Euromasters / MSc / MSci and BSc projects. The general area of study is the physics of anyons and emergent phenomena.

Research

Research Interests:

• Various aspects of boundary conformal field theory (BCFT) and CFTs with defects. I have organized several workshops on these topics: a 2017 workshop at Chicheley Hall sponsored by the Royal Society, a 2019 workshop at the Perimeter Institute. I also organized a workshop in 2021 at the MITP in Mainz.

• Topological quantum field theory (TQFT) and category theory; with Sanjaye Ramgoolam, I am organizing a journal club on these and related topics.

• Relations between TQFTs and CFTs

• Non-perturbative aspects of Superconformal Field Theories (SCFTs) and Supersymmetric Renormalization Group flows in various dimensions

• Topological quantum computation

• Conformal manifolds and exactly marginal deformations of SCFTs

• Relations between conformal manifolds and moduli spaces of vacua

• Emergent / accidental symmetries in Quantum Field Theory (QFT)

• Hidden operator algebras in QFT

• Understanding topological and analytic properties of the space of QFTs

• New microscopic models for CFTs in various dimensions

• Hitchin Systems, M5 branes, and SCFTs in 3D and 4D

Examples of research funding:

My grants / recent awards

• STFC consolidated grant 2023-2026 (approx £1.47M); with CRST group

• STFC consolidated grant 2020-2023 (approx £890,000); with CRST group

• Royal Society University Research Fellowship Renewal (£389,096.39); this grant partly supports an associated postdoctoral position (that started in the 2020-2021 acadmic year)

• STFC consolidated grant 2017-2020 (approx £700,000); with CRST group

• Grant to host BUSSTEPP@50 at QMUL from STFC (approx £105,000); with R. Monteiro, C. Papageorgakis, and R. Russo

• Royal Society Enhancement Award, "New Aspects of Conformal and Topological Field Theories Accross Dimensions"  (£103,067); this grant supports an associated PhD position (started October 2018), visitor's program, and computer cluster

• "Argyres-Douglas Theories, S¹ Reductions, and Topological Symmetries" (written in collaboration with Dr. Takahiro Nishinaka) was recently included in the  ^​Journal of Physics A Highlights of 2016 Collection

• Royal Society University Research Fellowship, "New Constraints and Phenomena in Quantum Field Theory" (£424,857)

Publications

See here

Supervision

List of PhD Students + Potential Projects

Current Students:

Chinmaya Bhargava: 2021-Present

Mahesh Balasubramanian: 2023-Present

Former Students:

Zoltan Laczko (joint with Maths): 2016-2020; went on to become a quantitative analyst at Man AHL in London

Linfeng Li: 2017-2021; went on to a postdoc at Korea Institute for Advanced Study

Rajath Radhakrishnan: 2018-2022; went on to a postdoc at ICTP Trieste

Potential Future Projects:

•  Algebraic operations on topological quantum field theory (TQFT)

•  Microscopic Models for New Rational Conformal Field Theories

•  New Constraints on the Supersymmetric Renormalization Group Flow in Three and Four Dimensions

•  Infinite Dimensional Symmetries and QFT in d > 2

Dissemination

Some Selected Talks

• 9/2021, GGI Workshop on Topological Properties of Gauge Theories, "Some Galois Actions in Topological Quantum Field Theory" (video)
• 7/2021, Hamburg ZMP colloquium, "aXb=c in 2+1D TQFT"
• 5/2019, Workshop on Beyond Rationality 2 (Woudschoten, Netherlands), "Galois Actions and QFT"
• 10/2018, Workshop on Non-perturbative Effects in Supersymmetric Field Theories (Natal, Brazil), "Flowing from 16 to 32 Supercharges" (video)
• 7/2018, Workshop on Supersymmetric Theories, Dualities and Deformations (Bern, Switzerland), “Flowing from 16 to 32 Supercharges” (video)
• 5/2018, GGI Workshop on Supersymmetric Quantum Field Theories in the Non-Perturbative Regime (Florence, Italy), “Duality and Generalized Duality"
• 4/2018, Oxford String Theory Seminar, “Duality and Generalized Duality"
• 4/2017, Joint SISSA/ICTP Seminar (Trieste, Italy), “New CFT/TFT Relations"
• 8/2016, Strings 2016 (Beijing, China), "Conformal Manifolds, Moduli Spaces, and Chiral Algebras," (video)
• 7/2016, GGI Workshop on Conformal Field Theories and Renormalization Group Flows in Dimensions d>2 (Florence, Italy), "Conformal Manifolds and Chiral Algebras"
• 3/2015, Princeton University, "Conformal Manifolds and Argyres-Douglas Theories"
• 1/2014, Quantum Fields Beyond Perturbation Theory (KITP, UC Santa Barbara), "Minimal Distances Between SCFTs," (video)
• 11/2013, Solvay Workshop on Exploring Higher Energy Physics (Brussels, Belgium), "Minimal Distances and the RG Flow"
• 5/2012, Planck 2012 (Warsaw, Poland), "R Symmetry and Emergent Symmetry"
• 11/2011, Harvard University, "R Symmetry and Non-Perturbative QFT"