# Why we consider identical particles for Bose-Einstein condensation?

Why we consider identical particles like identical composite bosons for BEC. Why we do not consider non identical particles of differnt masses etc?

• Look up the definition of a thermodynamic ensemble. The usual framework for BEC theory is quantum statistics, where you CAN consider a mixture of different spices, but it won't bring in much new physics in play, while generating substantial analytical complications... – MsTais Nov 29 '18 at 19:48

The irreducible representations of the Poincaré group are labelled by mass $$m$$ and the spin $$s$$.