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Related papers: On Krylov Complexity

200 papers

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

Recently, the out-of-time-ordered correlator(OTOC) and Krylov complexity have been studied actively as a measure of operator growth. OTOC is known to exhibit exponential growth in chaotic systems, which was confirmed in many previous works.…

Quantum Physics · Physics 2022-12-20 Seungjoo Baek

Krylov complexity has recently been proposed as a quantum probe of chaos. The Krylov exponent characterising the exponential growth of Krylov complexity is conjectured to upper-bound the Lyapunov exponent. We compute the Krylov and the…

High Energy Physics - Theory · Physics 2024-09-13 Shira Chapman , Saskia Demulder , Damián A. Galante , Sameer U. Sheorey , Osher Shoval

In closed quantum systems, Krylov complexity admits a geometric description; operator growth is equivalent to Hamiltonian flow in an emergent phase space whose structure is fixed by the Lanczos coefficients. We show that this picture…

High Energy Physics - Theory · Physics 2026-04-23 Arpan Bhattacharyya , S. Shajidul Haque , Jeff Murugan , Mpho Tladi , Hendrik J. R. Van Zyl

This is the contribution to Quarks'2018 conference proceedings. This contribution is devoted to the holographic description of chaos and quantum complexity in the strongly interacting systems out of equilibrium. In the first part of the…

High Energy Physics - Theory · Physics 2019-02-08 Dmitry S. Ageev

Krylov complexity is a novel measure of operator complexity that exhibits universal behavior and bounds a large class of other measures. In this letter, we generalize Krylov complexity from a closed system to an open system coupled to a…

Strongly Correlated Electrons · Physics 2023-08-11 Chang Liu , Haifeng Tang , Hui Zhai

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 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

In this work, we investigate spectral complexity and Krylov complexity in quantum billiard systems at finite temperature. We study both circle and stadium billiards as paradigmatic examples of integrable and non-integrable…

High Energy Physics - Theory · Physics 2024-03-06 Hugo A. Camargo , Viktor Jahnke , Hyun-Sik Jeong , Keun-Young Kim , Mitsuhiro Nishida

We study holographic Krylov complexity in the Coulomb branch of ${\cal N}=4$ SYM. Adopting the proposal that the time derivative of the Krylov complexity is dual to the proper radial momentum of a massive particle, we investigate two probe…

High Energy Physics - Theory · Physics 2026-03-17 Dimitrios Zoakos

In this paper, we study the Krylov complexity ($K$) from the planar/inflationary patch of the de Sitter space using the two mode squeezed state formalism in the presence of an effective field having sound speed $c_s$. From our analysis, we…

High Energy Physics - Theory · Physics 2023-06-09 Kiran Adhikari , Sayantan Choudhury

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

We investigate the Krylov complexity of thermofield double states in systems with mixed phase space, uncovering a direct correlation with the Brody distribution, which interpolates between Poisson and Wigner statistics. Our analysis spans…

High Energy Physics - Theory · Physics 2025-06-19 Kyoung-Bum Huh , Hyun-Sik Jeong , Leopoldo A. Pando Zayas , Juan F. Pedraza

The dynamics of quantum systems unfolds within a subspace of the state space or operator space, known as the Krylov space. This review presents the use of Krylov subspace methods to provide an efficient description of quantum evolution and…

A central problem in formulating a theory of quantum gravity is to determine the size and structure of the Hilbert space of black holes. Here we use a quantum dynamical Krylov complexity approach to calculate the Hilbert space dimension of…

High Energy Physics - Theory · Physics 2026-02-04 Vijay Balasubramanian , Rathindra Nath Das , Johanna Erdmenger , Jonathan Karl , Herman Verlinde

We investigate the complexity of states and operators evolved with the modular Hamiltonian by using the Krylov basis. In the first part, we formulate the problem for states and analyse different examples, including quantum mechanics,…

High Energy Physics - Theory · Physics 2023-06-27 Pawel Caputa , Javier M. Magan , Dimitrios Patramanis , Erik Tonni

In this work we develop a real-time Schwinger-Keldysh formulation of Krylov dynamics that treats Krylov complexity as an in-in observable generated by a closed time contour path integral. The resulting generating functional exposes an…

Quantum Physics · Physics 2026-02-03 Jeff Murugan , Hendrik J. R. van Zyl

We examine the complexity of quasi-static chaotic open quantum systems. As a prototypical example, we analytically compute the Krylov complexity of a slowly leaking hard-sphere gas using Berry's conjecture. We then connect it to the…

High Energy Physics - Theory · Physics 2023-12-05 Vyshnav Mohan

Many quantum gravitational frameworks, such as DBI inflation, k-essence, and effective field theories obtained by integrating out heavy modes, can lead to a non-trivial sound speed. Meanwhile, our universe can be described as an open…

General Relativity and Quantum Cosmology · Physics 2026-02-27 Shi-Cheng Liu , Lei-Hua Liu , Bichu Li , Hai-Qing Zhang , Peng-Zhang He

Krylov complexity, a quantum complexity measure which uniquely characterizes the spread of a quantum state or an operator, has recently been studied in the context of quantum chaos. However, the definitiveness of this measure as a chaos…

Quantum Physics · Physics 2025-09-12 Sreeram PG , J. Bharathi Kannan , Ranjan Modak , S. Aravinda