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Related papers: Local Quenches from a Krylov Perspective

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We study quench dynamics in a t-V chain of spinless fermions (equivalent to the spin-1/2 Heisenberg chain) with strong potential disorder. For this prototypical model of many-body localization we have recently argued that -- contrary to the…

Disordered Systems and Neural Networks · Physics 2022-11-29 M. Kiefer-Emmanouilidis , R. Unanyan , M. Fleischhauer , J. Sirker

We discuss the behaviour of holographic entanglement entropy following a local quench in 2+1 dimensional strongly coupled CFTs. The entanglement generated by the quench propagates along an emergent light-cone, reminiscent of the…

High Energy Physics - Theory · Physics 2016-05-04 Mukund Rangamani , Moshe Rozali , Alexandre Vincart-Emard

We continue the analysis of the Krylov complexity in the IP matrix model. In a previous paper, for a fundamental operator, it was shown that at zero temperature, the Krylov complexity oscillates and does not grow, but in the infinite…

High Energy Physics - Theory · Physics 2023-08-17 Norihiro Iizuka , Mitsuhiro Nishida

We study the effect of two simultaneous local quenches on the evolution of Loschmidt echo and entanglement entropy of a one dimensional transverse Ising model. In this work, one of the local quenches involves the connection of two spin-1/2…

Statistical Mechanics · Physics 2016-06-01 Atanu Rajak , Uma Divakaran

We study the statistical properties of Lanczos coefficients over an ensemble of random initial operators generating the Krylov space. We propose two statistical quantities that are important in characterizing the complexity: the average…

Quantum Physics · Physics 2025-03-20 Zhuoran Li , Wei Fan

We study the time evolution of single interval Renyi and entanglement entropies following local quantum quenches in two dimensional conformal field theories at finite temperature for which the locally excited states have a finite temporal…

High Energy Physics - Theory · Physics 2016-09-21 Justin R. David , Surbhi Khetrapal , S. Prem Kumar

This paper is devoted to the study of the evolution of holographic complexity after a local perturbation of the system at finite temperature. We calculate the complexity using both the complexity=action(CA) and the complexity=volume(CA)…

High Energy Physics - Theory · Physics 2019-12-11 Dmitry S. Ageev

We review the imaginary time path integral approach to the quench dynamics of conformal field theories. We show how this technique can be applied to the determination of the time dependence of correlation functions and entanglement entropy…

Statistical Mechanics · Physics 2016-06-29 Pasquale Calabrese , John Cardy

We study a particular type of local quench in a generic quantum critical one-dimensional system, using conformal field theory (CFT) techniques, and providing numerical checks of the results in free fermion systems. The system is initially…

Statistical Mechanics · Physics 2015-03-19 Jean-Marie Stéphan , Jérôme Dubail

Krylov complexity is a novel observable for detecting quantum chaos, and an indicator of a possible gravity dual. In this paper, we compute the Krylov complexity and the associated Lanczos coefficients in the SU(2) Yang-Mills theory, which…

High Energy Physics - Theory · Physics 2022-08-30 Shiyong Guo

We consider a local quench where two free-fermion half-chains are coupled via a defect. We show that the logarithmic increase of the entanglement entropy is governed by the same effective central charge which appears in the ground-state…

Statistical Mechanics · Physics 2015-06-05 Viktor Eisler , Ingo Peschel

Krylov complexity (K-complexity) is a measure of quantum state complexity that minimizes wavefunction spreading across all the possible bases. It serves as a key indicator of operator growth and quantum chaos. In this work, K-complexity and…

Quantum Physics · Physics 2025-10-08 J. Bharathi Kannan , Sreeram PG , Sanku Paul , S. Harshini Tekur , M. S. Santhanam

We study entanglement entropy after a double local quench in two-dimensional conformal field theories (CFTs), with any central charge $c>1$. In the holographic CFT, such a state with double-excitation is dual to an AdS space with two…

High Energy Physics - Theory · Physics 2020-02-19 Yuya Kusuki , Masamichi Miyaji

Krylov complexity measures the spread of the wavefunction in the Krylov basis, which is constructed using the Hamiltonian and an initial state. We investigate the evolution of the maximally entangled state in the Krylov basis for both…

High Energy Physics - Theory · Physics 2023-09-06 Johanna Erdmenger , Shao-Kai Jian , Zhuo-Yu Xian

Krylov complexity has recently emerged as a useful probe of operator growth and quantum dynamics in many-body systems and holographic dualities. In this paper we study its behavior in the Veneziano--Wosiek model, a supersymmetric matrix…

High Energy Physics - Theory · Physics 2026-03-24 Eleonora Alfinito , Matteo Beccaria

We apply the recently developed notion of complexity for field theory to a quantum quench through a critical point in 1+1 dimensions. We begin with a toy model consisting of a quantum harmonic oscillator, and show that complexity exhibits…

High Energy Physics - Theory · Physics 2019-03-06 Hugo A. Camargo , Pawel Caputa , Diptarka Das , Michal P. Heller , Ro Jefferson

Krylov complexity is a novel approach to study how an operator spreads over a specific basis. Recently, it has been stated that this quantity has a long-time saturation that depends on the amount of chaos in the system. Since this quantity…

Quantum Physics · Physics 2023-03-08 Bernardo L. Español , Diego A. Wisniacki

We investigate the real time dynamics of the radiation produced by a local quench in a $d$-dimensional conformal field theory (CFT) with $d>2$. Using the interpretation of the higher-dimensional twist operator as a conformal defect, we…

High Energy Physics - Theory · Physics 2025-02-28 Lorenzo Bianchi , Andrea Mattiello , Jacopo Sisti

We consider the recursion method applied to a generic 2pt function of a quantum system and show, in full generality, that the temperature dependence of the corresponding Lanczos coefficients is governed by integrable dynamics. After an…

High Energy Physics - Theory · Physics 2025-08-27 Nikolaos Angelinos , Debarghya Chakraborty , Anatoly Dymarsky

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 bounds the operator growth measured by the out of time…

High Energy Physics - Theory · Physics 2021-10-04 Anatoly Dymarsky , Michael Smolkin