Document Server@UHasselt
(3.246 recursos)
Repository of the University of Hasselt containing publications in the fields of statistics, computer science, information strategies and material from the Institute for behavioural sciences.
Mostrando recursos 1 - 20 de 25
1.
Reversals of chance in paradoxical games - Amengual, P.; Meurs, P.; CLEUREN, Bart; Toral, R.
We present two collective games with new paradoxical features when they are combined. Besides reproducing the so-called Parrondo effect, where a winning game is obtained from the alternation of two fair games, there also exists a current inversion when varying the mixing probability between the games. We show that this is a new effect insofar one of the games is an unbiased random walk without internal structure. We present a detailed study by means of a discrete-time Markov chain analysis, obtaining analytical expressions for the stationary probabilities for a finite number of players. We also provide qualitative insight into this...
2.
Fluctuation and dissipation of work in a Joule experiment - CLEUREN, Bart; VAN DEN BROECK, Christian; Kawai, R.
We elucidate the connection between various fluctuation theorems by a microcanonical version of the Crooks relation. We derive the microscopically exact expression for the work distribution in an idealized Joule experiment, namely, for a convex object moving at constant speed through an ideal gas. Analytic results are compared with molecular dynamics simulations of a hard disk gas.
3.
Fluctuation theorem for the effusion of an ideal gas - CLEUREN, Bart; VAN DEN BROECK, Christian; Kawai, B.
The probability distribution of the entropy production for the effusion of an ideal gas between two compartments is calculated explicitly. The fluctuation theorem is verified. The analytic results are in good agreement with numerical data from hard disk molecular dynamics simulations.
4.
Brownian refrigerator - VAN DEN BROECK, Christian
Onsager symmetry implies that a Brownian motor, driven by a temperature gradient, will also perform a refrigerator function upon loading. We analytically calculate the corresponding heat flow for an exactly solvable microscopic model and compare it with molecular dynamics simulations.
5.
Criticality on networks with topology-dependent interactions - Giuraniuc, C.V.; Hatchett, J.P.L.; Indekeu, J.O.; Leone, M.I.; Castillo, I.P.; Van Schaeybroeck, B.; VANDERZANDE, Carlo
Weighted scale-free networks with topology-dependent interactions are studied. It is shown that the possible universality classes of critical behavior, which are known to depend on topology, can also be explored by tuning the form of the interactions at fixed topology. For a model op opinion formation, simple mean field and scaling arguments show that a mapping ....
6.
Fluctuation theorem for black-body radiation - CLEUREN, Bart; VAN DEN BROECK, Christian
The fluctuation theorem is verified for black-body radiation, provided the bunching of photons is taken into account appropriately.
7.
Fluctuation theorem for entropy production during effusion of an ideal gas with momentum transfer - Wood, Kevin; VAN DEN BROECK, Christian; KAWAI, R.; Lindenberg, Katja
We derive an exact expression for entropy production during effusion of an ideal gas driven by momentum transfer in addition to energy and particle flux. Following the treatment in CLEUREN [Phys. Rev. E 74, 021117 (2006)], we construct a master equation formulation of the process and explicitly verify the thermodynamic fluctuation theorem, thereby directly exhibiting its extended applicability to particle flows and hence to hydrodynamic systems.
8.
Effects of disorder on synchronization of discrete phase-coupled oscillators - Wood, Kevin; VAN DEN BROECK, Christian; KAWAI, R.; Lindenberg, Katja
We study synchronization in populations of phase-coupled stochastic three-state oscillators characterized by a distribution of transition rates. We present results on an exactly solvable dimer as well as a systematic characterization of globally connected arrays of N types of oscillators (N=2,3,4) by exploring the linear stability of the nonsynchronous fixed point. We also provide results for globally coupled arrays where the transition rate of each unit is drawn from a uniform distribution of finite width. Even in the presence of transition rate disorder, numerical and analytical results point to a single phase transition to macroscopic synchrony at a critical value...
9.
Granular Brownian motor - CLEUREN, Bart; VAN DEN BROECK, Christian
An asymmetric object, undergoing dissipative collisions with surrounding particles, acquires a nonzero average velocity. The latter is calculated analytically by an expansion of the Boltzmann equation and the result is compared with Monte Carlo simulations. Copyright (c) EPLA, 2007
10.
Reversals of chance in paradoxical games - AMENGUAL, Pau; MEURS, Pascal; CLEUREN, Bart; Toral, R.
We present two collective games with new paradoxical features when they are combined. Besides reproducing the so-called Parrondo effect, where a winning game is obtained from the alternation of two fair games, there also exists a current inversion when varying the mixing probability between the games. We show that this is a new effect insofar one of the games is an unbiased random walk without internal structure. We present a detailed study by means of a discrete-time Markov chain analysis, obtaining analytical expressions for the stationary probabilities for a finite number of players. We also provide qualitative insight into this...
11.
Fluctuation and dissipation of work in a Joule experiment - CLEUREN, Bart; VAN DEN BROECK, Christian; Kawai, R.
We elucidate the connection between various fluctuation theorems by a microcanonical version of the Crooks relation. We derive the microscopically exact expression for the work distribution in an idealized Joule experiment, namely, for a convex object moving at constant speed through an ideal gas. Analytic results are compared with molecular dynamics simulations of a hard disk gas.
12.
Fluctuation theorem for the effusion of an ideal gas - CLEUREN, Bart; VAN DEN BROECK, Christian; Kawai, B.
The probability distribution of the entropy production for the effusion of an ideal gas between two compartments is calculated explicitly. The fluctuation theorem is verified. The analytic results are in good agreement with numerical data from hard disk molecular dynamics simulations.
13.
Brownian refrigerator - VAN DEN BROECK, Christian
Onsager symmetry implies that a Brownian motor, driven by a temperature gradient, will also perform a refrigerator function upon loading. We analytically calculate the corresponding heat flow for an exactly solvable microscopic model and compare it with molecular dynamics simulations.
14.
Criticality on networks with topology-dependent interactions - Giuraniuc, C.V.; Hatchett, J.P.L.; Indekeu, J.O.; Leone, M.I.; Castillo, I.P.; Van Schaeybroeck, B.; VANDERZANDE, Carlo
Weighted scale-free networks with topology-dependent interactions are studied. It is shown that the possible universality classes of critical behavior, which are known to depend on topology, can also be explored by tuning the form of the interactions at fixed topology. For a model op opinion formation, simple mean field and scaling arguments show that a mapping ....
15.
Critical behavior and synchronization of discrete stochastic phase-coupled oscillators - Wood, K.; VAN DEN BROECK, Christian; Kawai, R.; Lindenberg, K.
Synchronization of stochastic phase-coupled oscillators is known to occur but difficult to characterize because sufficiently complete analytic work is not yet within our reach, and thorough numerical description usually defies all resources. We present a discrete model that is sufficiently simple to be characterized in meaningful detail. In the mean-field limit, the model exhibits a supercritical Hopf bifurcation and global oscillatory behavior as coupling crosses a critical value. When coupling between units is strictly local, the model undergoes a continuous phase transition that we characterize numerically using finite-size scaling analysis. In particular, we explicitly rule out multistability and show that...
16.
Universality of synchrony: Critical behavior in a discrete model of stochastic phase-coupled oscillators - Wood, K.; VAN DEN BROECK, Christian; Kawai, R.; Lindenberg, K.
We present the simplest discrete model to date that leads to synchronization of stochastic phase-coupled oscillators. In the mean field limit, the model exhibits a Hopf bifurcation and global oscillatory behavior as coupling crosses a critical value. When coupling between units is strictly local, the model undergoes a continuous phase transition which we characterize numerically using finite-size scaling analysis. In particular, the onset of global synchrony is marked by signatures of the XY universality class, including the appropriate classical exponents beta and nu, a lower critical dimension d(lc)=2, and an upper critical dimension d(uc)=4.
17.
Dissipation: The phase-space perspective - KAWAI, R.; Parrondo, J. M. R.; VAN DEN BROECK, Christian
We show, through a refinement of the work theorem, that the average dissipation, upon perturbing a Hamiltonian system arbitrarily far out of equilibrium in a transition between two canonical equilibrium states, is exactly given by < W-diss >=< W >-Delta F=kTD(rho parallel to rho)=kT < ln(rho/rho)>, where rho and rho are the phase-space density of the system measured at the same intermediate but otherwise arbitrary point in time, for the forward and backward process. D(rho parallel to rho) is the relative entropy of rho versus rho. This result also implies general inequalities, which are significantly more accurate than the second...
18.
Chiral Brownian heat pump - VAN DEN BROEK, Martijn; VAN DEN BROECK, Christian
We present the exact analysis of a chiral Brownian motor and heat pump. Optimization of the construction predicts, for a nanoscale device, frequencies of the order of kHz and cooling rates of the order of femtojoule per second.
19.
The "footprints" of irreversibility - Gomez-Marin, A.; Parrondo, J. M. R.; VAN DEN BROECK, Christian
We reformulate the result for the entropy production given in Phys. Rev. Lett., 98 ( 2007) 080602 in terms of the relative entropy of microscopic trajectories. By a combination with the Crook's theorem, we identify the path variables that are sufficient to fully identify irreversibility. We show that work saturates the relative entropy, and derive the entropy production for stochastic descriptions. Copyright (c) EPLA, 2008.
20.
Slow topological time scale of knotted polymers - Orlandini, Enzo; Stella, Attilio L.; VANDERZANDE, Carlo; Zonta, Francesco
We investigate the Rouse dynamics of a flexible ring polymer with a prime knot. Within a Monte Carlo approach, we locate the knot, follow its diffusion and observe the fluctuations of its length. A topological time scale that is slower than the Rouse one is found to determine the long time behavior of several dynamical quantities. The value of the associated dynamical exponent is Zeta T = 2.32 +/- 0.1.
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