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We use a real-space renormalization group (RSRG) to study the low temperature dynamics of kinetically constrained Ising chains (KCICs). We consider the cases of the Fredrickson-Andersen (FA) model, the East model, and the partially…

Statistical Mechanics · Physics 2009-11-10 Stephen Whitelam , Juan P. Garrahan

The renormalization group (RG) properties of quantum gravity are explored, using the vielbein and the spin connection as the fundamental field variables. The scale dependent effective action is required to be invariant both under space time…

High Energy Physics - Theory · Physics 2015-05-20 J. -E. Daum , M. Reuter

The density matrix renormalization group (DMRG) method generates the low-energy states of linear systems of $N$ sites with a few degrees of freedom at each site by starting with a small system and adding sites step by step while keeping…

Strongly Correlated Electrons · Physics 2016-10-05 Manoranjan Kumar , Dayasindhu Dey , Aslam Parvej , S. Ramasesha , Zoltán G. Soos

We use our recently developed functional renormalization group (FRG) approach for quantum spin systems to investigate the phase diagram of the frustrated $J_{1}J_{2}J_{3}$ quantum Heisenberg model on a cubic lattice. From a simple…

Strongly Correlated Electrons · Physics 2023-02-28 Dmytro Tarasevych , Andreas Rückriegel , Savio Keupert , Vasilios Mitsiioannou , Peter Kopietz

We introduce a hybrid approach to applying the density matrix renormalization group (DMRG) to continuous systems, combining a grid approximation along one direction with a finite Gaussian basis set along the remaining two directions. This…

Chemical Physics · Physics 2017-08-02 E. Miles Stoudenmire , Steven R. White

In many-body systems with quenched disorder, dynamical observables can be singular not only at the critical point, but in an extended region of the paramagnetic phase as well. These Griffiths singularities are due to rare regions, which are…

Disordered Systems and Neural Networks · Physics 2022-01-19 István A. Kovács , Ferenc Iglói

We develop a theoretical approach to ``spontaneous stochasticity'' in classical dynamical systems that are nearly singular and weakly perturbed by noise. This phenomenon is associated to a breakdown in uniqueness of solutions for fixed…

Statistical Mechanics · Physics 2020-11-04 Gregory L. Eyink , Dmytro Bandak

The spin-1/2 quantum Ising chain in a transverse random magnetic field is studied by means of the density-matrix renormalization group. The system evolves from an ordered to a paramagnetic state as the amplitude of the random field is…

Disordered Systems and Neural Networks · Physics 2009-10-30 A. Juozapavicius , S. Caprara , A. Rosengren

We study the effect of spatial correlations in the quenched disorder on random quantum magnets at and near a quantum critical point. In the random transverse field Ising systems disorder correlations that decay algebraically with an…

Disordered Systems and Neural Networks · Physics 2009-10-31 H. Rieger , F. Igloi

In this article we apply background-independent renormalization group methods to spin foam quantum gravity. It is aimed at extending and elucidating the analysis of a companion letter, in which the existence of a fixed point in the…

General Relativity and Quantum Cosmology · Physics 2017-07-21 Benjamin Bahr , Sebastian Steinhaus

We revisit Fradkin and Raby's real-space renormalization-group method to study the quantum Z_2 gauge theory defined on links forming a two-dimensional square lattice. Following an old suggestion of theirs, a systematic perturbation…

Statistical Mechanics · Physics 2021-02-02 Steve T. Paik

We develop a comprehensive Renormalization Group (RG) approach to criticality in open Floquet systems, where dissipation enables the system to reach a well-defined Floquet steady state of finite entropy, and all observables are synchronized…

Statistical Mechanics · Physics 2020-10-13 Steven Mathey , Sebastian Diehl

We study the ground-state phase diagram of the Ashkin-Teller random quantum spin chain by means of a generalization of the strong-disorder renormalization group. In addition to the conventional paramagnetic and ferromagnetic (Baxter)…

Strongly Correlated Electrons · Physics 2014-01-14 Fawaz Hrahsheh , Rajesh Narayanan , José A. Hoyos , Thomas Vojta

We consider the effects of weak measurements on the quantum critical ground state of the one-dimensional (a) tricritical and (b) critical quantum Ising model, by measuring in (a) the local energy and in (b) the local spin operator in a…

Statistical Mechanics · Physics 2024-09-04 Rushikesh A. Patil , Andreas W. W. Ludwig

The renormalization group (RG) in statistical physics focuses on ground-state properties of equilibrium systems. However, it is unclear how it should be generalized to nonunitary quantum dynamics caused by dissipation and measurement…

Statistical Mechanics · Physics 2026-05-12 Atsushi Oyaizu , Hongchao Li , Masaya Nakagawa , Masahito Ueda

A class of continuum models with a critical end point is considered whose Hamiltonian ${\mathcal{H}}[\phi,\psi]$ involves two densities: a primary order-parameter field, $\phi$, and a secondary (noncritical) one, $\psi$. Field-theoretic…

Statistical Mechanics · Physics 2009-11-07 H. W. Diehl , M. Smock

We develop a density-matrix renormalization group (DMRG) algorithm for the simulation of quantum circuits. This algorithm can be seen as the extension of time-dependent DMRG from the usual situation of hermitian Hamiltonian matrices to…

We use a tensor network strong-disorder renormalization group (tSDRG) method to study spin-1 random Heisenberg antiferromagnetic chains. The ground state of the clean spin-1 Heisenberg chain with uniform nearest-neighbor couplings is a…

Disordered Systems and Neural Networks · Physics 2020-04-22 Zheng-Lin Tsai , Pochung Chen , Yu-Cheng Lin

We consider the critical and off-critical properties at the boundary of the random transverse-field Ising spin chain when the distribution of the couplings and/or transverse fields, at a distance $l$ from the surface, deviates from its…

Statistical Mechanics · Physics 2016-08-15 Dragi Karevski , Róbert Juhász , Loïc Turban , Ferenc Iglói

The random quantum $q$-state clock and Potts models are studied in 2 and 3 dimensions. The existence of Griffiths phases is tested in the 2D case with $q=6$ by sampling the integrated probability distribution of local susceptibilities of…

Disordered Systems and Neural Networks · Physics 2023-07-26 Valentin Anfray , Christophe Chatelain