Hi! I just found that vide on Youtube: http://www.youtube.com/watch?v=veU6hK3jMH4&feature=watch-vrec And something is not quite ok for me. In ~1:00 Krauss says, that in flat universe model universe would expand slower and slower but would never quite stop expanding. On the other hand, in last 4 minutes he says that energy of the vacuum would would cause accelerating expansion of the universe (which is a feature of open universe, like he says in the begining), which is flat at the same moment. How is that consistent?