The change of the entropy in natural time under time-reversal in the Olami–Feder–Christensen earthquake model

Here, we analyze the Olami–Feder–Christensen (OFC) model for earthquakes in a new time domain, termed natural time χ. We show that there exists a non-zero change ΔS of the entropy in natural time upon time reversal. This reveals a breaking of the time symmetry, thus reflecting the predictability in the OFC model.

► In the OFC model there exists a non zero change ΔS of the entropy in natural time under time reversal.
► In the OFC earthquake model the non zero value of ΔS signals the breaking of the time symmetry.
► The non zero value of ΔS reveals the predictability in the OFC earthquake model.