Toward scalable simulations of lattice gauge theories on quantum computers

Abstract

In this talk I will present a framework for simulating a discretized U(1) gauge theory with dynamical matter on a digital quantum computer, that is scalable towards an arbitrary number of spacial dimensions. We adopt the quantum link model method to regularize the gauge Hilbert space but, contrary to the prevailing literature, we employ the Wilson approach to discretize the fermion fields. We present a detailed resource counting in terms of qubit register size and number of gates to perform real time Hamiltonian evolution, a task which is unfeasible with classical methods except for very small -unphysical- system sizes. We also demonstrate in IBM-Q quantum hardware a variational calculation in a minimal system which displays the characteristic string-breaking physics with the creation of a particle-antiparticle pair. Ref: https://arxiv.org/abs/2005.10271 (to appear in PRD)