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Global firing induced by noise or diversity in excitable media

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 Added by Claudio Tessone
 Publication date 2005
  fields Physics
and research's language is English




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We develop a theory for the emergence of global firings in non-identical excitable systems subject to noise. Three different dynamical regimes arise: sub-threshold motion, where all elements remain confined near the fixed point; coherent pulsations, where a macroscopic fraction fire simultaneously; and incoherent pulsations, where units fire in a disordered fashion. We also show that the mechanism for global firing is generic: it arises from degradation of entrainment originated either by noise or by diversity.



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