[HTML][HTML] Random walk with chaotically driven bias

SJ Kim, M Naruse, M Aono, H Hori, T Akimoto - Scientific reports, 2016 - nature.com
Scientific reports, 2016nature.com
We investigate two types of random walks with a fluctuating probability (bias) in which the
random walker jumps to the right. One is a 'time-quenched framework'using bias time series
such as periodic, quasi-periodic, and chaotic time series (chaotically driven bias). The other
is a 'time-annealed framework'using the fluctuating bias generated by a stochastic process,
which is not quenched in time. We show that the diffusive properties in the time-quenched
framework can be characterised by the ensemble average of the time-averaged variance …
Abstract
We investigate two types of random walks with a fluctuating probability (bias) in which the random walker jumps to the right. One is a ‘time-quenched framework’ using bias time series such as periodic, quasi-periodic, and chaotic time series (chaotically driven bias). The other is a ‘time-annealed framework’ using the fluctuating bias generated by a stochastic process, which is not quenched in time. We show that the diffusive properties in the time-quenched framework can be characterised by the ensemble average of the time-averaged variance (ETVAR), whereas the ensemble average of the time-averaged mean square displacement (ETMSD) fails to capture the diffusion, even when the total bias is zero. We demonstrate that the ETVAR increases linearly with time, and the diffusion coefficient can be estimated by the time average of the local diffusion coefficient. In the time-annealed framework, we analytically and numerically show normal diffusion and superdiffusion, similar to the Lévy walk. Our findings will lead to new developments in information and communication technologies, such as efficient energy transfer for information propagation and quick solution searching.
nature.com
Showing the best result for this search. See all results