English
Related papers

Related papers: Explicit Connections Between Krylov and Nielsen Co…

200 papers

We set up, at the abstract Hilbert space setting, the general question on when an inverse linear problem induced by an operator of Friedrichs type admits solutions belonging to (the closure of) the Krylov subspace associated to such…

Functional Analysis · Mathematics 2024-07-23 Noe Angelo Caruso , Alessandro Michelangeli

We introduce and review a new complexity measure, called `Krylov complexity', which takes its origins in the field of quantum-chaotic dynamics, serving as a canonical measure of operator growth and spreading. Krylov complexity, underpinned…

High Energy Physics - Theory · Physics 2025-07-10 Eliezer Rabinovici , Adrián Sánchez-Garrido , Ruth Shir , Julian Sonner

We study the effect of supersymmetry breaking on Krylov complexity in the $\mathcal{N}=2$ SYK model under irrelevant and mass deformations of the Hamiltonian. The irrelevant deformation breaks $\mathcal{N}=2$ supersymmetry down to…

High Energy Physics - Theory · Physics 2026-02-04 James Chryssanthacopoulos , David Vegh

In classical frameworks as the Euclidean space, positive definite kernels as well as their analytic properties are explicitly available and can be incorporated directly in kernel-based learning algorithms. This is different if the…

Numerical Analysis · Mathematics 2023-01-18 Wolfgang Erb

This Thesis explores the notion of Krylov complexity as a probe of quantum chaos and as a candidate for holographic complexity. The first Part is devoted to presenting the fundamental notions required to conduct research in this area.…

High Energy Physics - Theory · Physics 2024-07-08 A. Sánchez-Garrido

In this paper we study Krylov complexity in the presence of single and multiple operators in the DSSYK model, where we can use the analytical techniques coming from chord diagrammatics. One of the results we obtain is that it showcases the…

High Energy Physics - Theory · Physics 2025-11-12 Marco Ambrosini , Eliezer Rabinovici , Julian Sonner

We investigate Krylov complexity of the fermion chain operator which consists of multiple Majorana fermions in the double-scaled SYK (DSSYK) model with finite temperature. Using the fact that Krylov complexity is computable from two-point…

High Energy Physics - Theory · Physics 2024-07-19 Takanori Anegawa , Ryota Watanabe

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 study the Krylov state complexity of the Sachdev-Ye-Kitaev (SYK) model for $N \le 28$ Majorana fermions with $q$-body fermion interaction with $q=4,6,8$ for a range of sparse parameter $k$ that controls the number of remaining terms in…

High Energy Physics - Theory · Physics 2025-08-25 Raghav G. Jha , Ranadeep Roy

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

In recent years two Krylov subspace methods have been proposed for solving skew symmetric linear systems, one based on the minimum residual condition, the other on the Galerkin condition. We give new, algorithm-independent proofs that in…

Numerical Analysis · Mathematics 2015-12-02 Stanley C. Eisenstat

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

Parallel implementations of Krylov subspace methods often help to accelerate the procedure of finding an approximate solution of a linear system. However, such parallelization coupled with asynchronous and out-of-order execution often…

Mathematical Software · Computer Science 2023-02-09 Roman Iakymchuk , Jose I. Aliaga

In Nielsen's geometric approach to quantum complexity, the introduction of a suitable geometrical space, based on the Lie group formed by fundamental operators, facilitates the identification of complexity through geodesic distance in the…

Quantum Physics · Physics 2025-04-03 Satyaki Chowdhury , Martin Bojowald , Jakub Mielczarek

We extend the CV conjecture to quantum states of two-mode Hermitian systems using the framework of information geometry. Specifically, we conjecture that the Krylov complexity of a quantum state equals the volume of the Fubini-Study metric.…

High Energy Physics - Theory · Physics 2026-05-22 Ke-Hong Zhai , Lei-Hua Liu , Hai-Qing Zhang

The abstract issue of 'Krylov solvability' is extensively discussed for the inverse problem $Af = g$ where $A$ is a (possibly unbounded) linear operator on an infinite-dimensional Hilbert space, and $g$ is a datum in the range of $A$. The…

Numerical Analysis · Mathematics 2020-12-16 Noe Caruso , Alessandro Michelangeli

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

Recently, a novel measure for the complexity of operator growth is proposed based on Lanczos algorithm and Krylov recursion method. We study this Krylov complexity in quantum mechanical systems derived from some well-known local toric…

High Energy Physics - Theory · Physics 2023-04-27 Bao-ning Du , Min-xin Huang

We compare Krylov's state complexity with an information-geometric (IG) measure of complexity for the quantum evolution of two-level systems. Focusing on qubit dynamics on the Bloch sphere, we analyze evolutions generated by stationary and…

Quantum Physics · Physics 2026-01-28 Carlo Cafaro , Emma Clements , Vishnu Vardhan Anuboyina

Normalized information distance (NID) uses the theoretical notion of Kolmogorov complexity, which for practical purposes is approximated by the length of the compressed version of the file involved, using a real-world compression program.…

Computational Complexity · Computer Science 2009-10-23 Sebastiaan A. Terwijn , Leen Torenvliet , Paul M. B. Vitanyi