Long time behaviour of four point velocity correlations in hard disk systems

✍ Scribed by I.M. de Schepper; M.H. Ernst

• Publisher: Elsevier Science
• Year: 1978
• Tongue: English
• Weight: 797 KB
• Volume: 93
• Category: Article
• ISSN: 0378-4371
• DOI: 10.1016/0378-4371(78)90179-6

✦ Synopsis

An asymptotic long time expansion is derived for the time dependent super Burnett coefficient which is the time derivative of the fourth cumulant of displacement of a tagged particle in a hard disk system or, alternatively, it is the ordered time integral over the cumulant of the four point velocity correlation function. Use has been made of a kinetic theory for hard disk systems. In contrast to classical theories the super Burnett coefficient shows a rather strong divergence, proportional to t. The theoretical prediction is compared with results from molecular dynamics