Mechanisms of evolution of avalanches in regular graphs.

Phys Rev E Stat Nonlin Soft Matter Phys

Department of Chemistry, University of Cambridge, Cambridge, United Kingdom.

Published: June 2013

A mapping of avalanches occurring in the zero-temperature random-field Ising model to life periods of a population experiencing immigration is established. Such a mapping allows the microscopic criteria for the occurrence of an infinite avalanche in a q-regular graph to be determined. A key factor for an avalanche of spin flips to become infinite is that it interacts in an optimal way with previously flipped spins. Based on these criteria, we explain why an infinite avalanche can occur in q-regular graphs only for q>3 and suggest that this criterion might be relevant for other systems. The generating function techniques developed for branching processes are applied to obtain analytical expressions for the durations, pulse shapes, and power spectra of the avalanches. The results show that only very long avalanches exhibit a significant degree of universality.

Download full-text PDF

Source
http://dx.doi.org/10.1103/PhysRevE.87.062122DOI Listing

Publication Analysis

Top Keywords

infinite avalanche
8
mechanisms evolution
4
avalanches
4
evolution avalanches
4
avalanches regular
4
regular graphs
4
graphs mapping
4
mapping avalanches
4
avalanches occurring
4
occurring zero-temperature
4

Similar Publications

Ductile and brittle yielding of athermal amorphous solids: A mean-field paradigm beyond the random-field Ising model.

Phys Rev E

October 2024

Institut für Theoretische Physik, University of Göttingen, Friedrich-Hund-Platz 1, 37077 Göttingen, Germany and Department of Mathematics, King's College London, London WC2R 2LS, United Kingdom.

Amorphous solids can yield in either a ductile or brittle manner under strain: plastic deformation can set in gradually, or abruptly through a macroscopic stress drop. Developing a unified theory describing both ductile and brittle yielding constitutes a fundamental challenge of nonequilibrium statistical physics. Recently, it has been proposed that, in the absence of thermal effects, the nature of the yielding transition is controlled by physics akin to that of the quasistatically driven random field Ising model (RFIM), which has served as the paradigm for understanding the effect of quenched disorder in slowly driven systems with short-ranged interactions.

View Article and Find Full Text PDF

Collection efficiencies of cylindrical and plane parallel ionization chambers: analytical and numerical results and implications for experimentally determined correction factors.

Phys Med Biol

July 2024

Group of Medical Physics and Biomathematics, Instituto de Investigación Sanitaria de Santiago (IDIS), 15706 Santiago de Compostela, Spain.

Article Synopsis
  • A new formula for collection efficiency, fGauss, was derived for cylindrical ionization chambers operating in pulsed radiation beams based on Boag's volume recombination model that includes free electrons.
  • Validation of fGauss and a parallel plate chamber formula, fexp, showed they predict similar collection efficiencies when specific geometric equivalence conditions are met.
  • The study found that changes in collection efficiencies due to electric field charge screening were minimal, and fGauss and fexp accurately described efficiencies within 0.03% to 21.3% at varying radiation doses, with slight differences observed between chamber types at higher doses.
View Article and Find Full Text PDF

Domain convexification: A simple model for invasion processes.

Phys Rev E

October 2023

Institut Lumière Matière, Université de Lyon, Université Claude Bernard Lyon 1, CNRS UMR5306, Campus de la Doua, F-69622 Villeurbanne, France.

We propose an invasion model where domains grow up to their convex hulls and merge when they overlap. This model can be seen as a continuum and isotropic counterpart of bootstrap percolation models. From numerical investigations of the model starting with randomly deposited overlapping disks on a plane, we find an invasion transition that occurs via macroscopic avalanches.

View Article and Find Full Text PDF

Many-body localized (MBL) systems fail to reach thermal equilibrium under their own dynamics, even though they are interacting, nonintegrable, and in an extensively excited state. One instability toward thermalization of MBL systems is the so-called "avalanche," where a locally thermalizing rare region is able to spread thermalization through the full system. The spreading of the avalanche may be modeled and numerically studied in finite one-dimensional MBL systems by weakly coupling an infinite-temperature bath to one end of the system.

View Article and Find Full Text PDF

Taming numerical errors in simulations of continuous variable non-Gaussian state preparation.

Sci Rep

October 2022

Department of Optics, Palacký University, 17. listopadu 1192/12, 771 46, Olomouc, Czech Republic.

Article Synopsis
  • The text discusses the importance of numerical simulation in preparing continuous variable quantum states to enhance quantum information processing methods.* -
  • It highlights the use of Fock state representation, which approximates infinite-dimensional spaces with finite vector spaces to compute the coherent displacement operator more accurately.* -
  • The proposed enhanced method analyzes a non-Gaussian state preparation scheme, comparing various detection mechanisms to create qubit-like superpositions involving non-linearly squeezed states and single photons.*
View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!