We discuss various experiments on the time decay of velocity autocorrelation functions in billiards. We perform new experiments and find results which are compatible with an exponential mixing hypothesis, first put forward by Friedman and Martin, [FM]: they do not seem compatible with the stretched exponentials believed, in spite of [FM] and more recently of Chernov, [C], to describe the mixing. The analysis led us to several byproducts: we obtain information about the normal diffusive nature of the motion and we consider the probability distribution of the number of collisions in time tm (as t\to\infty$) finding a strong dependence on some geometric characteristics of the locus of the billiards obstacles.
Billiards correlation functions / Gallavotti, Giovanni; Garrido, P.. - In: JOURNAL OF STATISTICAL PHYSICS. - ISSN 0022-4715. - STAMPA. - 76:(1994), pp. 549-585. [10.1007/BF02188675]
Billiards correlation functions
GALLAVOTTI, Giovanni;
1994
Abstract
We discuss various experiments on the time decay of velocity autocorrelation functions in billiards. We perform new experiments and find results which are compatible with an exponential mixing hypothesis, first put forward by Friedman and Martin, [FM]: they do not seem compatible with the stretched exponentials believed, in spite of [FM] and more recently of Chernov, [C], to describe the mixing. The analysis led us to several byproducts: we obtain information about the normal diffusive nature of the motion and we consider the probability distribution of the number of collisions in time tm (as t\to\infty$) finding a strong dependence on some geometric characteristics of the locus of the billiards obstacles.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
