### 31.10.2013 (Thursday)

#### How many is different? Answer from ideal Bose gas

Regular Seminar Jeong-Hyuck Park (Sogang U.)

 at: 14:00 QMWroom lecture theatre abstract: How many H2O molecules are needed to form water? While the precise answer is not known, it is clear that the answer should be a finite number rather than infinity. We revisit with care the ideal Bose gas confined in a cubic box which is discussed in most statistical physics textbooks. We show that the isobar of the ideal gas zigzags on the temperature-volume plane featuring a boiling-like' discrete phase transition, provided the number of particles is equal to or greater than a particular value: 7616. This demonstrates for the first time how a finite system can feature a mathematical singularity and realize the notion of Emergence', without resorting to the thermodynamic limit. ref: arXiv:1310.5580