PubMed Health⌕ Search

Biomedical subjects

Mario Markus

Publications and source records attributed to Mario Markus.

2 recordsLinked to original sources

Fluctuation theorem for a deterministic one-particle system.

A Duffing oscillator is driven by a sum of N chaotic time series. These time series are solutions of the undriven Duffing equation. It is shown that N=1 is sufficient to render the fluctuation theorem [Phys. Rev. Lett. 74, 2694 (1995)]; J. Math. Phys. 41, 4061 (2000)]; Adv. Phys. 51, 1529 (2002)]] for the power J(tau) averaged within intervals of length tau . In particular, the probabilities p( J(tau) ) follow a nearly Gaussian distribution. Also, ln[p( J(tau) )/p(- J(tau) )] versus J(tau) can be fitted by strikingly linear functions, the slopes being proportional to tau for large tau . These results indicate that validity of the fluctuation theorem requires neither a many-particle system nor a stochastic process, which are requirements used in previous works.

Journal Article↗

On-off intermittency and intermingledlike basins in a granular medium.

Molecular dynamic simulations of a medium consisting of disks in a periodically tilted box yield two dynamic modes differing considerably in the total potential and kinetic energies of the disks. Depending on parameters, these modes display the following features: (i) hysteresis (coexistence of the two modes in phase space); (ii) intermingledlike basins of attraction (uncertainty exponent indistinguishable from zero); (iii) two-state on-off intermittency; and (iv) bimodal velocity distributions. Bifurcations are defined by a cross-shaped phase diagram.

Journal Article↗