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Related papers: Sharp Transitions for Subsystem Complexity

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We study the quantum complexity of time evolution in large-$N$ chaotic systems, with the SYK model as our main example. This complexity is expected to increase linearly for exponential time prior to saturating at its maximum value, and is…

High Energy Physics - Theory · Physics 2020-06-05 Vijay Balasubramanian , Matthew DeCross , Arjun Kar , Onkar Parrikar

Quantum computational complexity estimates the difficulty of constructing quantum states from elementary operations, a problem of prime importance for quantum computation. Surprisingly, this quantity can also serve to study a completely…

High Energy Physics - Theory · Physics 2022-03-02 Shira Chapman , Giuseppe Policastro

Using a recent proposal of circuit complexity in quantum field theories introduced by Jefferson and Myers, we compute the time evolution of the complexity following a smooth mass quench characterized by a time scale $\delta t$ in a free…

High Energy Physics - Theory · Physics 2018-06-14 Daniel W. F. Alves , Giancarlo Camilo

Reliable processing of quantum information for developing quantum technologies requires precise control of out-of-equilibrium many-bodysystems. This is a highly challenging task as the fragility of quantum states to external perturbations…

The holographic complexity of a static spherically symmetric black hole, defined as the volume of an extremal surface, grows linearly with time at late times in general relativity. The growth comes from a region at a constant transverse…

High Energy Physics - Theory · Physics 2025-08-11 Friðrik Freyr Gautason , Vyshnav Mohan , Lárus Thorlacius

A quantum system can undergo a continuous phase transition at the absolute zero of temperature as some parameter entering its Hamiltonian is varied. These transitions are particularly interesting for, in contrast to their classical finite…

Condensed Matter · Physics 2009-10-28 S. L. Sondhi , S. M. Girvin , J. P. Carini , D. Shahar

We study the temporal evolution of the circuit complexity for a subsystem in harmonic lattices after a global quantum quench of the mass parameter, choosing the initial reduced density matrix as the reference state. Upper and lower bounds…

High Energy Physics - Theory · Physics 2021-05-13 Giuseppe Di Giulio , Erik Tonni

Holographic complexity, as the bulk dual of quantum complexity, encodes the geometric structure of black hole interiors. Motivated by the complexity=anything proposal, we introduce the spectral representation for generating functions…

High Energy Physics - Theory · Physics 2026-04-21 Masamichi Miyaji , Shan-Ming Ruan , Shono Shibuya , Kazuyoshi Yano

We study circuit complexity for spatial regions in holographic field theories. We study analogues based on the entanglement wedge of the bulk quantities appearing in the "complexity = volume" and "complexity = action" conjectures. We…

High Energy Physics - Theory · Physics 2019-04-29 Cesar A. Agón , Matthew Headrick , Brian Swingle

Circuit complexity, defined as the minimum circuit size required for implementing a particular Boolean computation, is a foundational concept in computer science. Determining circuit complexity is believed to be a hard computational problem…

Statistical Mechanics · Physics 2025-07-08 Claudio Chamon , Andrei E. Ruckenstein , Eduardo R. Mucciolo , Ran Canetti

The rate of complexification of a quantum state is conjectured to be bounded from above by the average energy of the state. A different conjecture relates the complexity of a holographic CFT state to the on-shell gravitational action of a…

High Energy Physics - Theory · Physics 2018-03-09 Mudassir Moosa

Simulating time evolution of generic quantum many-body systems using classical numerical approaches has an exponentially growing cost either with evolution time or with the system size. In this work, we present a polynomially scaling hybrid…

Quantum Physics · Physics 2023-09-18 Nikita Astrakhantsev , Sheng-Hsuan Lin , Frank Pollmann , Adam Smith

We study the complexity of both time-optimal and time sub-optimal quantum Hamiltonian evolutions connecting arbitrary source and a target states on the Bloch sphere equipped with the Fubini-Study metric. This investigation is performed in a…

Quantum Physics · Physics 2024-11-28 Carlo Cafaro , Leonardo Rossetti , Paul M. Alsing

Dual-unitary circuits are a class of locally-interacting quantum many-body systems displaying unitary dynamics also when the roles of space and time are exchanged. These systems have recently emerged as a remarkable framework where certain…

Statistical Mechanics · Physics 2023-07-04 Alessandro Foligno , Bruno Bertini

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 (CV) conjectures. We conclude using the CV conjecture that the rate of…

High Energy Physics - Theory · Physics 2018-11-15 Dean Carmi , Shira Chapman , Hugo Marrochio , Robert C. Myers , Sotaro Sugishita

In optimal quantum-mechanical evolutions, motion can take place along paths of minimal length within an optimal time frame. Alternatively, optimal evolutions may occur along established paths without any waste of energy resources and…

Quantum Physics · Physics 2026-01-16 Carlo Cafaro , James Schneeloch

We study the evolution of holographic complexity in various AdS/CFT models containing cosmological crunch singularities. We find that a notion of complexity measured by extremal bulk volumes tends to decrease as the singularity is…

High Energy Physics - Theory · Physics 2016-02-17 Jose L. F. Barbon , Eliezer Rabinovici

In this article, we investigate the quantum circuit complexity and entanglement entropy in the recently studied black hole gas framework using the two-mode squeezed states formalism written in arbitrary dimensional spatially flat…

High Energy Physics - Theory · Physics 2021-09-03 Kiran Adhikari , Sayantan Choudhury , Satyaki Chowdhury , K. Shirish , Abinash Swain

We study the growth and saturation of Krylov spread (K-) complexity under random quantum circuits. In Haar-random unitary evolution, we show that, for large system sizes, K-complexity grows linearly before saturating at a late-time value of…

Quantum Physics · Physics 2025-05-22 Himanshu Sahu , Aranya Bhattacharya , Pingal Pratyush Nath

We present the results of our computation of the subregion complexity and also compare it with the entanglement entropy of a $2+1$--dimensional holographic superconductor which has a fully backreacted gravity dual with a stable ground sate.…

High Energy Physics - Theory · Physics 2020-04-08 Avik Chakraborty