JuliaDynamics / TransitionsInTimeseries.jl

Transition Indicators / Early Warning Signals / Regime Shifts / Change Point Detection
MIT License
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Covariant Lyapunov vectors as indicators #3

Open Datseris opened 1 year ago

Datseris commented 1 year ago

Indicator summary

I came across this from a presentation of Sarah Hallerberg in Dynamics Days 2022 Aberdeen. They worked on how covariant lyapunov vectors behave close to a critical transition. I quote from their abstract:

Studying critical transitions in several models of fast-slow systems, i.e., a network of coupled FitzHugh-Nagumo oscillators, models for Josephson junctions, and the Hindmarsh-Rose model, we find that tangencies between covariant Lyapunov vectors are a common and maybe generic feature during critical transitions.

more importantly:

In the presence of noise, we find the alignment of covariant Lyapunov vectors and changes in finite-time Lyapunov exponents to be more successful in announcing critical transitions than common indicator variables as, e.g., finite-time estimates of the variance.

Reference

https://journals.aps.org/pre/abstract/10.1103/PhysRevE.96.032220

and also this paper for the method to estimate CLVs from data: https://paperswithcode.com/paper/estimating-covariant-lyapunov-vectors-from

Codebase

Nope. But I can ask Nahal Sharafi, perhaps she is willing to share.

Implementation plan

Not yet.