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Related papers: Towards verifications of Krylov complexity

200 papers

Krylov subspace methods in quantum dynamics identify the minimal subspace in which a process unfolds. To date, their use is restricted to time evolutions governed by time-independent generators. We introduce a generalization valid for…

Quantum Physics · Physics 2025-01-27 Kazutaka Takahashi , Adolfo del Campo

Solving short and long time dynamics of closed quantum many-body systems is one of the main challenges of both atomic and condensed matter physics. For locally interacting closed systems, the dynamics of local observables can always be…

Quantum Physics · Physics 2025-11-20 Nicolas Loizeau , Berislav Buča , Dries Sels

We study the operator growth in open quantum systems with dephasing dissipation terms, extending the Krylov complexity formalism of Phys. Rev. X 9, 041017. Our results are based on the study of the dissipative $q$-body Sachdev-Ye-Kitaev…

Quantum Physics · Physics 2023-03-10 Budhaditya Bhattacharjee , Xiangyu Cao , Pratik Nandy , Tanay Pathak

We investigate Krylov complexity in open quantum systems using Lindblad master equations for bosonic bath models, with particular emphasis on the Caldeira--Leggett model. Krylov complexity is computed from the moments of the two-point…

High Energy Physics - Theory · Physics 2026-04-22 Arpan Bhattacharyya , Sayed Gool , S. Shajidul Haque

We use Krylov complexity to study operator growth in the $q$-body dissipative SYK model, where the dissipation is modeled by linear and random $p$-body Lindblad operators. In the large $q$ limit, we analytically establish the linear growth…

Quantum Physics · Physics 2024-01-18 Budhaditya Bhattacharjee , Pratik Nandy , Tanay Pathak

We study Krylov complexity in Lifshitz-type Dirac field theories with a generic dynamical critical exponent $z$. By computing the Lanczos coefficients for massless and massive cases, we analyze the growth and saturation behavior of Krylov…

High Energy Physics - Theory · Physics 2025-11-11 Hamid R. Imani , Komeil Babaei Velni , M. Reza Mohammadi Mozaffar

We show that Hall's exact uncertainty relation acquires a simple geometric form in the Krylov basis generated by the Liouvillian. In this canonical operator frame, the uncertainty equality implies that the operator amplitude vector evolves…

Quantum Physics · Physics 2026-02-10 Mohsen Alishahiha , Souvik Banerjee

Spread complexity uses the distribution of support of a time-evolving state in the Krylov basis to quantify dispersal across accessible dimensions of a Hilbert space. Here, we describe how variations in initial conditions, the Hamiltonian,…

High Energy Physics - Theory · Physics 2025-11-19 Vijay Balasubramanian , Pawel Caputa , Joan Simón

In this paper we study the notion of complexity under time evolution in chaotic quantum systems with holographic duals. Continuing on from our previous work, we turn our attention to the issue of Krylov complexity upon the insertion of a…

High Energy Physics - Theory · Physics 2025-03-10 Marco Ambrosini , Eliezer Rabinovici , Adrián Sánchez-Garrido , Ruth Shir , Julian Sonner

Considering the large-$q$ expansion of the Sachdev-Ye-Kitaev (SYK) model in the two-stage limit, we compute the Lanczos coefficients, Krylov complexity, and the higher Krylov cumulants in subleading order, along with the $t/q$ effects. The…

High Energy Physics - Theory · Physics 2023-08-21 Budhaditya Bhattacharjee , Pratik Nandy , Tanay Pathak

We examine the effective field theory (EFT) of maximal chaos through the lens of Krylov complexity and the Universal Operator Growth Hypothesis. We test the relationship between two measures of quantum chaos: out-of-time-ordered correlators…

High Energy Physics - Theory · Physics 2026-03-16 Saskia Demulder , Maria Knysh , Andrew Rolph

For large scale electronic structure calculation, the Krylov subspace method is introduced to calculate the one-body density matrix instead of the eigenstates of given Hamiltonian. This method provides an efficient way to extract the…

Materials Science · Physics 2009-11-10 Ryu Takayama , Takeo Hoshi , Takeo Fujiwara

Quantum complexity, suitably defined, has been suggested as an important probe of late-time dynamics of black holes, particularly in the context of AdS/CFT. A notion of quantum complexity can be effectively captured by quantifying the…

High Energy Physics - Theory · Physics 2022-04-20 E. Rabinovici , A. Sánchez-Garrido , R. Shir , J. Sonner

We investigate Krylov state complexity as a probe of the quantum Mpemba effect in quantum spin chains. For models without global $U(1)$ symmetry, Krylov complexity exhibits clear Mpemba-like crossings, consistent with conventional…

High Energy Physics - Theory · Physics 2025-11-04 Mohsen Alishahiha , Mohammad Javad Vasli

In this paper, we studied a set of generalised Krylov complexity for operator growth. We demonstrate their universal features at both initial times and long times using half-analytical technique as well as numerical results. In particular,…

High Energy Physics - Theory · Physics 2023-12-12 Zhong-Ying Fan

Recently, the propagation of information through quantum many-body systems, developed to study quantum chaos, have found many application from black holes to disordered spin systems. Among other quantitative tools, Krylov complexity has…

Quantum Physics · Physics 2025-03-11 Aranya Bhattacharya , Pingal Pratyush Nath , Himanshu Sahu

We analyze the properties of Krylov state complexity in qubit dynamics, considering a single qubit and a qubit pair. A geometrical picture of the Krylov complexity is discussed for the single-qubit case, whereas it becomes non-trivial for…

Quantum Physics · Physics 2025-04-18 Siddharth Seetharaman , Chetanya Singh , Rejish Nath

In this work, we propose a quantum-mechanically measurable basis for the computation of spread complexity. Current literature focuses on computing different powers of the Hamiltonian to construct a basis for the Krylov state space and the…

Quantum Physics · Physics 2024-11-05 Saud Čindrak , Adrian Paschke , Lina Jaurigue , Kathy Lüdge

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

An algorithm for constructing a $J$-orthogonal basis of the extended Krylov subspace $\mathcal{K}_{r,s}=\operatorname{range}\{u,Hu, H^2u,$ $ \ldots, $ $H^{2r-1}u, H^{-1}u, H^{-2}u, \ldots, H^{-2s}u\},$ where $H \in \mathbb{R}^{2n \times…

Numerical Analysis · Mathematics 2022-02-28 Peter Benner , Heike Faßbender , Michel-Niklas Senn