Why the Universe Needs Dark Energy

Part 2 in our Dark Energy series. Part 1: Check out our sister channel Crash Course Physics to learn more about the basic foudations of Physics: Get your own Space Time t-shirt at Tweet at us! @pbsspacetime Email us! pbsspacetime [at] gmail [dot] com Comment on Reddit: Help translate our videos! Now that we know the universe will continue to expand forever, we can begin to complete the first Friedmann equation, and determine the shape and geometry of our universe. At first glance, it would seem that the equation doesn’t quite add up, and that our universe is a hyperbolic plane. But when we add in the cosmological constant, the equation balances out, and we return to a flat universe. _____________________ COMMENTS: Deiter Meena Jack W Mychelly Goulart Tomek Wooff Mr B ______________________ Written and hosted by Matt O’Dowd Made by Kornhaber Brown (www.kornhaberbrown.com)