English

Spacetime as a quantum circuit

High Energy Physics - Theory 2021-05-05 v2 General Relativity and Quantum Cosmology Quantum Physics

Abstract

We propose that finite cutoff regions of holographic spacetimes represent quantum circuits that map between boundary states at different times and Wilsonian cutoffs, and that the complexity of those quantum circuits is given by the gravitational action. The optimal circuit minimizes the gravitational action. This is a generalization of both the "complexity equals volume" conjecture to unoptimized circuits, and path integral optimization to finite cutoffs. Using tools from holographic TTˉT\bar T, we find that surfaces of constant scalar curvature play a special role in optimizing quantum circuits. We also find an interesting connection of our proposal to kinematic space, and discuss possible circuit representations and gate counting interpretations of the gravitational action.

Keywords

Cite

@article{arxiv.2101.01185,
  title  = {Spacetime as a quantum circuit},
  author = {A. Ramesh Chandra and Jan de Boer and Mario Flory and Michal P. Heller and Sergio Hörtner and Andrew Rolph},
  journal= {arXiv preprint arXiv:2101.01185},
  year   = {2021}
}

Comments

26 pages, 2 figures; v2: published version, minor clarifications added

R2 v1 2026-06-23T21:46:13.436Z