Persistent dynamic correlations in self-organized critical systems away from their critical point

TL;DR

This paper demonstrates that self-organized critical systems maintain correlated dynamics and long-term memory even when driven away from their critical point, challenging previous assumptions of randomness in such systems.

Contribution

It reveals persistent temporal correlations in SOC systems under external forcing, extending understanding beyond the critical point.

Findings

Correlations persist at all forcing levels except overdriven conditions.

Memory of past events influences current dynamics.

Contradicts the idea that SOC time series are purely random superpositions.

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.