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arXiv · 1903.07007

A quantum cellular automaton for one-dimensional QED

Pablo Arrighi·Cédric Bény·Terry Farrelly
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Abstract

We propose a discrete spacetime formulation of quantum electrodynamics in one-dimension (a.k.a the Schwinger model) in terms of quantum cellular automata, i.e. translationally invariant circuits of local quantum gates. These have exact gauge covariance and a maximum speed of information propagation. In this picture, the interacting quantum field theory is defined as a "convergent" sequence of quantum cellular automata, parameterized by the spacetime lattice spacing---encompassing the notions of continuum limit and renormalization, and at the same time providing a quantum simulation algorithm for the dynamics.

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Pablo Arrighi, Cédric Bény, Terry Farrelly. 2020-02-04. A quantum cellular automaton for one-dimensional QED. https://doi.org/10.1007/s11128-019-2555-4

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