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How Many Universes Are There?

How Many Universes Are There?

How Many Universes Are There?

Season 5 Episode 34

14:03

Black Hole Harmonics

Black Hole Harmonics

Black Hole Harmonics

Season 5 Episode 35

13:11

Loop Quantum Gravity Explained

Loop Quantum Gravity Explained

Loop Quantum Gravity Explained

Season 5 Episode 36

13:49

Is Time Travel Impossible?

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

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?

Does Life Need a Multiverse to Exist?

Season 5 Episode 39

13:09

Can You Observe a Typical Universe?

Can You Observe a Typical Universe?

Can You Observe a Typical Universe?

Season 5 Episode 40

13:36

Is The Universe Finite?

Is The Universe Finite?

Is The Universe Finite?

Season 5 Episode 41

12:25

The Doomsday Argument

The Doomsday Argument

The Doomsday Argument

Season 5 Episode 42

12:50

Do Black Holes Create New Universes?

Do Black Holes Create New Universes?

Do Black Holes Create New Universes?

Season 5 Episode 43

12:24

How To Detect a Neutrino

How To Detect a Neutrino

How To Detect a Neutrino

Season 5 Episode 44

9:54

How To Capture Black Holes

How To Capture Black Holes

How To Capture Black Holes

Season 5 Episode 45

12:02

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PBS Space Time

Is Pluto a Planet?

Season 5 Episode 33

You know what a planet is, right? A big round thing that orbits a star. Uh, not so fast. The surprisingly vicious debate over the planetary status of Pluto has given us a fascinating glimpse into what a scientific definition really is. And perhaps the word planet is too vague to be used as a scientific definition at all.

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