Take the 2-minute tour ×
Physics Stack Exchange is a question and answer site for active researchers, academics and students of physics. It's 100% free, no registration required.

There is Bose-Einstein condensate (BEC) for non-interacting boson systems. Can we prove the existence of BEC for interacting systems?

share|improve this question
add comment

1 Answer

Bogoliubov proved long, long ago that the condensate is stable against weak interactions. The interactions scatter some fraction of bosons out of the lowest-energy single-particle state ("depleting" the condensate), but off-diagonal long range order remains. For a nice introduction to Bogoliubov's theory see Ben Simon's lectures

http://www.tcm.phy.cam.ac.uk/~bds10/tp3.html

(lecture 9). "Weak" is relative though, and in fact real bose liquids with even decently strong interactions can retain a condensate. Bose condensation turns out to be a very robust phenomenon.

share|improve this answer
    
Thanks for your answer and suggested reading. –  Jeremy Apr 21 '13 at 3:13
add comment

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.