I am writing for a question on the algorithm for classical Monte Carlo simulation of spin models. From the simulations I performed on classical O(2), O(3) and O(4) models it turned out that the autocorrelation time is quite large, let's say of about 80 o 90, for the energy density observable. I just would like to understand better if there is a particular reason for such a big tau and which kind of algorithm is really used for the simulation: 

Swendsen-Wang , Wolff single cluster or even something else? This is also because the term ”sweep” is quite unusual when cluster algorithms are concerned.

I really thank you all for your help. 

Best regards,

Rachele Nerattini

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   Rachele Nerattini
   Dip. di Fisica e Astronomia, Università di Firenze
   Via G. Sansone, 1, 50019 Sesto Fiorentino (FI), Italy
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