Why is the universe flat?

Cosmic inflation is a theory that was proposed in the 1980s by cosmologist Alan Guth to answer some of the most fundamental questions of the origins of our universe. It also solved the Horizon Problem and the Flatness Problem. Help us translate our videos! http://www.youtube.com/timedtext_cs_panel?c=UC7DdEm33SyaTDtWYGO2CwdA&tab=2 If you liked this video check out these: The Most MYSTERIOUS Object in the Universe https://www.youtube.com/watch?v=GHsQl-k3syg Are perpetual motion machines possible? https://www.youtube.com/watch?v=4b8ZsFszE8I Subscribe - http://www.youtube.com/subscription_center?add_user=physicswoman http://instagram.com/thephysicsgirl http://www.physicsgirl.org/twitter http://www.physicsgirl.org/facebook http://www.physicsgirl.org/