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PBS Space Time
Why the Universe Needs Dark Energy
Season 2
Episode 27
We know the universe will continue to expand forever, so now 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.
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18:19
What if, just before we reach the bottom, we find out that reductionism fails?

19:03
The biggest news in cosmology in recent years is that dark energy may be fading away.

18:50
Does this also explain why there are no aliens?

16:58
Quantum energy teleportation may be as close as we get to transporter beams. But how close is that?

14:50
Why is there any matter in the universe? A new antimatter breakthrough at LHC holds clues.

16:30
There’s an extremely good chance that Earth once did have a ring system.

17:23
How is it possible to tell if a space rock will one day collide with the Earth?

15:58
Did you know that many of us have up to 4% neanderthal DNA?

16:35
What if the Big Bang was just an endless cycle?

19:39
Why are billions suddenly being pumped into fusion startups?

16:36
The universe should've collapsed after the Big Bang, but a light Higgs boson let us exist.

14:30
Maybe dark energy doesn't exist?