Complex sentence: Brownian dynamics is one of the popular techniques of solving the Langevin equation, but the hydrodynamic interaction in Brownian dynamics is highly simplified and normally includes only the one body result (isolated particle).
Split into simpler sentences: Brownian dynamics is one of the popular techniques of solving the Langevin equation. But the hydrodynamic interaction considered in Brownian dynamics is very naive, normally including only the single body result (isolated particle).