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What Caused the Big Bang?

What Caused the Big Bang?

Season 5 Episode 28
13:12
What Happened Before the Big Bang?

What Happened Before the Big Bang?

Season 5 Episode 29
10:23
How To Become an Astrophysicist

How To Become an Astrophysicist

Season 5 Episode 30
12:45
Is Earth's Magnetic Field Reversing?

Is Earth's Magnetic Field Reversing?

Season 5 Episode 31
12:46
Could We Terraform Mars?

Could We Terraform Mars?

Season 5 Episode 32
15:33
Is Pluto a Planet?

Is Pluto a Planet?

Season 5 Episode 33
14:03
How Many Universes Are There?

How Many Universes Are There?

Season 5 Episode 34
14:03
Black Hole Harmonics

Black Hole Harmonics

Season 5 Episode 35
13:11
Loop Quantum Gravity Explained

Loop Quantum Gravity Explained

Season 5 Episode 36
13:49
Is Time Travel Impossible?

Is Time Travel Impossible?

Season 5 Episode 37
12:33
Why We Might Be Alone in the Universe

Why We Might Be Alone in the Universe

Season 5 Episode 38
12:24
Does Life Need a Multiverse to Exist?

Does Life Need a Multiverse to Exist?

Season 5 Episode 39
13:09
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PBS Space Time

Did Time Start at the Big Bang?

Season 5 Episode 27

A hundred years ago we discovered the beginning of the universe. Observations of the retreating galaxies by Edwin Hubble and Vesto Slipher, combined with Einstein’s then-brand-new general theory of relativity, revealed that our universe is expanding.