Going from being down -500 + to being up almost 200 points is not something that takes in a regular market without an invisible hand playing a role in the market to lift prices up. Only a Central bank intervention could move prices like this in one day within hours
http://www.reuters.com/article/us-us...-idUSKBN1341PE
http://www.reuters.com/article/us-us...-idUSKBN1341PE