Research
My research is driven by a central question: why does the observable universe contain almost no antimatter? Addressing this requires fully nonperturbative, real-time simulations of quantum field theories — a regime where conventional methods such as perturbative expansions or Euclidean lattice Monte Carlo break down entirely. Quantum computers and tensor networks, uniquely suited to simulating real-time quantum evolution, offer a path forward.
My work develops the QFT formalism, quantum and classical algorithms, and qubit embeddings needed to make real-time simulations a practical tool for fundamental physics. Baryogenesis serves as a concrete and demanding target that shapes these formal and algorithmic developments, while the resulting tools apply broadly to strongly coupled QFTs and physics beyond the Standard Model.
A complete list of publications is on iNSPIRE and Google Scholar.
Chiral Fermions and Lattice Chiral Gauge Theories
Realistic simulations of the Standard Model require careful handling of chiral symmetry. There are two related problems on the lattice, both of which I am actively working on.
The “easy” problem concerns theories like QCD with an anomalous global chiral symmetry. While the Ginsparg-Wilson (GW) relation provides a precise understanding of chiral symmetry on the Euclidean lattice, its implementation in Hamiltonian frameworks needed for real-time quantum simulation has remained incomplete. I have developed Hamiltonian generalizations of GW fermions that yield lattice theories with exact chiral symmetry and correct anomaly structure.
The “hard” problem concerns gauging the chiral symmetry, as in the electroweak sector of the Standard Model. This problem remains open even on Euclidean lattices and stands among the deepest unsolved problems in theoretical physics. I am using tensor-network formulations to study anomaly cancellation in 1+1-dimensional chiral gauge theories, providing nonperturbative checks of consistency conditions that are otherwise difficult to probe, while also enabling concrete numerical investigations.
Real-Time Simulations for Baryogenesis
Baryogenesis — the dynamical process that generated the observed matter-antimatter asymmetry in the early universe — requires out-of-equilibrium, nonperturbative dynamics that are inaccessible to perturbative methods and Euclidean lattice simulations. Real-time Hamiltonian simulations, using tensor networks and quantum computers, offer a path to studying these phenomena from first principles.
I am developing a systematic program I call the baryogenesis ladder: a sequence of increasingly realistic models progressing from 1+1 dimensions toward fully dynamical gauge and Higgs fields in 3+1 dimensions, with quantum algorithms developed at each stage. As the first rung, I used tensor-network simulations with dynamical fermions to study charge-asymmetry generation during fermion–bubble scattering across a first-order phase transition. These simulations introduced new real-time observables that directly quantify asymmetry production — quantities inaccessible to perturbative treatments and Euclidean lattice methods.
Qubit Regularization of Quantum Field Theories
A central question in lattice field theory is whether a quantum field theory can be regularized using a system with a finite-dimensional local Hilbert space — a “qubit model”. This is both a foundational question about the nature of QFTs and a practical one: quantum computers natively operate on finite-dimensional systems, so such a regularization is a prerequisite for quantum simulation.
My work on qubit regularization has focused on asymptotically free sigma models as prototypes for non-Abelian gauge theories. I showed that the (1+1)D O(3) nonlinear sigma model — including its asymptotic freedom and topological θ vacua — can be reproduced by a simple spin-1/2 Hamiltonian with two qubits per site. A key challenge was constructing sign-problem-free formulations to enable classical Monte Carlo verification of the qubit models, which we achieved using worldline methods. More recently, the program has been extended to O(N) models and to understanding how anomaly matching constrains which qubit regularizations are possible.
Quantum Simulation on Near-Term Hardware
Qubit regularization provides a Hamiltonian formulation suitable for implementation on quantum hardware. A separate set of questions then arises: how do we actually reach the continuum limit on a finite quantum device, and what platforms are best suited for simulating specific models?
I have worked on mapping the qubit-regularized O(3) sigma model onto cold-atom platforms, identifying a dimensional reduction strategy that allows one to approach the continuum limit with fewer physical qubits. I have also studied Floquet engineering in Ising models, showing that a strongly driven Ising chain reproduces effective Heisenberg dynamics — providing a practical route to engineering the interactions needed for sigma model simulation on existing hardware.
Few-Body Nuclear Physics and Pionless EFT
During my PhD I worked on non-relativistic few-body systems using pionless effective field theory (EFT) — the systematic low-energy expansion for nuclear systems well below the pion mass. One line of work used the large-N_c expansion to derive relationships among two-nucleon contact couplings that are otherwise independent in the EFT, providing a deeper organizational principle consistent with experiment. I also developed a worldline (spacetime lattice) approach to few-body systems as an alternative to Hamiltonian methods, enabling worm-algorithm Monte Carlo for fixed particle-number sectors.