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Updated: Jul 7, 2026

Optogenetic Stimulation of Escape Behavior in Drosophila melanogaster
Published on: January 25, 2013
Anomalous escape governed by thermal 1/f noise
1University of Augsburg, Institute of Physics, Universitätsstr. 1, D-86135 Augsburg, Germany.
Abstract:
We present an analytic study for subdiffusive escape of overdamped particles out of a cusp-shaped parabolic potential well which are driven by thermal, fractional Gaussian noise with a 1/omega 1-alpha power spectrum. This long-standing challenge becomes mathematically tractable by use of a generalized Langevin dynamics via its corresponding non-Markovian, time-convolutionless master equation: We find that the escape is governed asymptotically by a power-law whose exponent depends exponentially on the ratio of barrier height and temperature. This result is in distinct contrast to a description with a corresponding subdiffusive fractional Fokker-Planck approach, thus providing experimentalists an amenable testbed to differentiate between the two escape scenarios.
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