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Title: Persistent correlations in self-organized critical systems away of their critical point

Abstract

We show that correlated dynamics and long time memory persist in self-organized criticality (SOC) systems even when forced away from the defined critical point that exists at vanishing drive strength. These temporal correlations are found for all levels of external forcing as long as the system is not overdriven. They arise from the same physical mechanism that produces the temporal correlations found at the vanishing drive limit, namely the memory of past events stored in the system profile. The existence of these correlations contradicts the notion that a SOC time series is simply a random superposition of events with sizes distributed as a power law, as has been suggested by previous studies.

Authors:
 [1];  [2];  [3];  [3]
  1. British Antarctic Survey, Cambridge, UK
  2. University of Alaska
  3. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Laboratory Directed Research and Development (LDRD) Program
OSTI Identifier:
978262
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physica A: Statistical Mechanics and its Applications; Journal Volume: 373
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; CRITICALITY; PHYSICS; ORNL; Tubulent transport; correlations; self-organized criticality

Citation Formats

Woodard, Ryan, Newman, David E, Sanchez, Raul, and Carreras, Benjamin A. Persistent correlations in self-organized critical systems away of their critical point. United States: N. p., 2007. Web. doi:10.1016/j.physa.2006.05.001.
Woodard, Ryan, Newman, David E, Sanchez, Raul, & Carreras, Benjamin A. Persistent correlations in self-organized critical systems away of their critical point. United States. doi:10.1016/j.physa.2006.05.001.
Woodard, Ryan, Newman, David E, Sanchez, Raul, and Carreras, Benjamin A. Mon . "Persistent correlations in self-organized critical systems away of their critical point". United States. doi:10.1016/j.physa.2006.05.001.
@article{osti_978262,
title = {Persistent correlations in self-organized critical systems away of their critical point},
author = {Woodard, Ryan and Newman, David E and Sanchez, Raul and Carreras, Benjamin A},
abstractNote = {We show that correlated dynamics and long time memory persist in self-organized criticality (SOC) systems even when forced away from the defined critical point that exists at vanishing drive strength. These temporal correlations are found for all levels of external forcing as long as the system is not overdriven. They arise from the same physical mechanism that produces the temporal correlations found at the vanishing drive limit, namely the memory of past events stored in the system profile. The existence of these correlations contradicts the notion that a SOC time series is simply a random superposition of events with sizes distributed as a power law, as has been suggested by previous studies.},
doi = {10.1016/j.physa.2006.05.001},
journal = {Physica A: Statistical Mechanics and its Applications},
number = ,
volume = 373,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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