Operator Growth Bounds from Graph Theory

نویسندگان

چکیده

Let $A$ and $B$ be local operators in Hamiltonian quantum systems with $N $ degrees of freedom finite-dimensional Hilbert space. We prove that the commutator norm $\lVert [A(t),B]\rVert$ is upper bounded by a topological combinatorial problem: counting irreducible weighted paths between two points on Hamiltonian's factor graph. Our bounds sharpen existing Lieb-Robinson removing extraneous growth. In drawn from zero-mean random ensembles few-body interactions, we stronger ensemble-averaged out-of-time-ordered correlator $\mathbb{E}\left[ \lVert [A(t),B]\rVert_F^2\right]$. such Erd\"os-R\'enyi graphs, scrambling time $t_{\mathrm{s}}$, at which $\lvert [A(t),B]\rVert_F=\mathrm{\Theta}(1)$, almost surely $t_{\mathrm{s}}=\mathrm{\Omega}(\sqrt{\log N})$; further $t_{\mathrm{s}}=\mathrm{\Omega}(\log N) to high order perturbation theory $1/N$. constrain infinite temperature chaos $q$-local Sachdev-Ye-Kitaev model any $1/N$; leading order, our bound Lyapunov exponent within 2 known result $q>2$. also speculate implications theorems for conjectured holographic descriptions gravity.

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Bounds on the restrained Roman domination number of a graph

A {em Roman dominating function} on a graph $G$ is a function$f:V(G)rightarrow {0,1,2}$ satisfying the condition that everyvertex $u$ for which $f(u) = 0$ is adjacent to at least one vertex$v$ for which $f(v) =2$. {color{blue}A {em restrained Roman dominating}function} $f$ is a {color{blue} Roman dominating function if the vertices with label 0 inducea subgraph with no isolated vertex.} The wei...

متن کامل

Bounds for the Co-PI index of a graph

In this paper, we present some inequalities for the Co-PI index involving the some topological indices, the number of vertices and edges, and the maximum degree. After that, we give a result for trees. In addition, we give some inequalities for the largest eigenvalue of the Co-PI matrix of G.

متن کامل

Bounds on First Reformulated Zagreb Index of Graph

The first reformulated Zagreb index $EM_1(G)$ of a simple graph $G$ is defined as the sum of the terms $(d_u+d_v-2)^2$ over all edges $uv$ of $G .$ In this paper, the various upper and lower bounds for the first reformulated Zagreb index of a connected graph interms of other topological indices are obtained.

متن کامل

Optimal multiplexed sensing: bounds, conditions and a graph theory link.

Measuring an array of variables is central to many systems, including imagers (array of pixels), spectrometers (array of spectral bands) and lighting systems. Each of the measurements, however, is prone to noise and potential sensor saturation. It is recognized by a growing number of methods that such problems can be reduced by multiplexing the measured variables. In each measurement, multiple ...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

ژورنال

عنوان ژورنال: Communications in Mathematical Physics

سال: 2021

ISSN: ['0010-3616', '1432-0916']

DOI: https://doi.org/10.1007/s00220-021-04151-6