Quantum computational complexity from quantum information to black holes and back

S Chapman, G Policastro - The European Physical Journal C, 2022 - Springer
Quantum computational complexity estimates the difficulty of constructing quantum states
from elementary operations, a problem of prime importance for quantum computation …

An introduction to the SYK model

V Rosenhaus - Journal of Physics A: Mathematical and …, 2019 - iopscience.iop.org
Abstract The Sachdev–Ye–Kitaev (SYK) model is a strongly coupled, quantum many-body
system that is chaotic, nearly conformally invariant, and exactly solvable. This remarkable …

Quantum chaos and the complexity of spread of states

V Balasubramanian, P Caputa, JM Magan, Q Wu - Physical Review D, 2022 - APS
We propose a measure of quantum state complexity defined by minimizing the spread of the
wave function over all choices of basis. Our measure is controlled by the “survival amplitude” …

Geometry of Krylov complexity

P Caputa, JM Magan, D Patramanis - Physical Review Research, 2022 - APS
We develop a geometric approach to operator growth and Krylov complexity in many-body
quantum systems governed by symmetries. We start by showing a direct link between a …

Pseudoentropy in and Timelike Entanglement Entropy

K Doi, J Harper, A Mollabashi, T Takayanagi, Y Taki - Physical Review Letters, 2023 - APS
We study holographic entanglement entropy in dS/CFT and introduce timelike entanglement
entropy in CFTs. Both of them take complex values in general and are related with each …

Circuit complexity in quantum field theory

RA Jefferson, RC Myers - Journal of High Energy Physics, 2017 - Springer
A bstract Motivated by recent studies of holographic complexity, we examine the question of
circuit complexity in quantum field theory. We provide a quantum circuit model for the …

Quantum complexity and topological phases of matter

P Caputa, S Liu - Physical Review B, 2022 - APS
In this work, we find that the complexity of quantum many-body states, defined as a spread in
the Krylov basis, may serve as a probe that distinguishes topological phases of matter. We …

Toward a definition of complexity for quantum field theory states

S Chapman, MP Heller, H Marrochio, F Pastawski - Physical review letters, 2018 - APS
We investigate notions of complexity of states in continuous many-body quantum systems.
We focus on Gaussian states which include ground states of free quantum field theories and …

Krylov complexity in conformal field theory

A Dymarsky, M Smolkin - Physical Review D, 2021 - APS
Krylov complexity, or K-complexity for short, has recently emerged as a new probe of chaos
in quantum systems. It is a measure of operator growth in Krylov space, which conjecturally …

On the time dependence of holographic complexity

D Carmi, S Chapman, H Marrochio, RC Myers… - Journal of High Energy …, 2017 - Springer
A bstract We evaluate the full time dependence of holographic complexity in various eternal
black hole backgrounds using both the complexity= action (CA) and the complexity= volume …