espressomd / espresso

The ESPResSo package
https://espressomd.org
GNU General Public License v3.0
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Noise behavior of stokesian dynamics and other thermostats differ #3840

Closed fweik closed 4 years ago

fweik commented 4 years ago

SD seems to use a counter based noise source, as do the other thermostats. The counter value is derived from the simulation time by calculating sim_time / time_step, which means that if the users resets the time, the noise is repeated. This differs from the other thermostats, where the noise is derive from a monotonous counter which can not be reset. Also the SD version leads to correlated noise if the time step is changed.

jngrad commented 4 years ago

The long-term solution is for SD to use the same framework as the other thermostats, once the framework is refactored to use a single counter.