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PBS Space Time

Is It Irrational to Believe in Aliens?

Video duration: 6:49Expires: 10/29/20Video has closed captioning.

Aliens! Could humans really be alone in this expansive universe? And if we're not, how come we've never made contact with other intelligent life? Everyone's thought about it; especially members of the scientific community. Join Gabe as he presents some of the most popular theories that scientists use to rationalize their support or skepticism of the existence of aliens.

Episodes of PBS Space Time46

Video thumbnail: PBS Space Time How Cosmic Inflation Flattened the Universe

PBS Space Time

How Cosmic Inflation Flattened the Universe

The Big Bang Theory only gets us part of the way there.

10:17

How Cosmic Inflation Flattened the Universe

10:17

Video thumbnail: PBS Space Time Why is the Earth Round and the Milky Way Flat?

PBS Space Time

Why is the Earth Round and the Milky Way Flat?

Our universe is not a very diverse place when it comes to shapes.

10:48

Why is the Earth Round and the Milky Way Flat?

10:48

Video thumbnail: PBS Space Time What’s Wrong With the Big Bang Theory?

PBS Space Time

What’s Wrong With the Big Bang Theory?

We continue our search for a grand unifying theory of the Big Bang!

9:56

What’s Wrong With the Big Bang Theory?

9:56

Video thumbnail: PBS Space Time Why the Big Bang Definitely Happened

PBS Space Time

Why the Big Bang Definitely Happened

The actual moment of ‘the Big Bang’ is still a bit of a grey area within physics.

8:54

Why the Big Bang Definitely Happened

8:54

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