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Natural time and 1/f "noise"

P. A. Varotsos·N. V. Sarlis·E. S. Skordas
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Abstract

Seismic electric signals have been found to obey the ubiquitous $1/f^a$ behavior [{\em Phys. Rev. E} {\bf 66}, 011902(2002)]. The newly introduced concept of natural time enables the study of the dynamic evolution of a complex system and identifies when the system enters the critical stage. On the basis of this concept, a simple model is proposed here which exhibits the $1/f^a$ behavior with $a$ close to unity. Furthermore, we present recent data of electric signals, which when analyzed in the natural time domain are found to exhibit {\em critical} dynamics and hence can be classified as seismic electric signals.

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P. A. Varotsos, N. V. Sarlis, E. S. Skordas. 2007-05-15. Natural time and 1/f "noise". https://arxiv.org/abs/cond-mat/0703683

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