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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
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?

Season 5 Episode 41
12:25
The Doomsday Argument

The Doomsday Argument

Season 5 Episode 42
12:50
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

Season 5 Episode 44
9:54
How To Capture Black Holes

How To Capture Black Holes

Season 5 Episode 45
12:02
What if Singularities DO NOT Exist?

What if Singularities DO NOT Exist?

Season 10 Episode 1
14:44
What Happens If We Nuke Space?

What Happens If We Nuke Space?

Season 10 Episode 2
15:13
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PBS Space Time

Loop Quantum Gravity Explained

Season 5 Episode 36

It’s time we talked about loop quantum gravity. What exactly is it? What are the loops? And can it really defeat string theory in our quest for a Theory of Everything?

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Season
Perpetual Motion From Negative Mass?
14:28
Challenge question: if 1kg of apples is $5 and 2kg is $10, how much is -1kg of apples?
The Crisis in Cosmology
13:17
The hubble constant--the rate of expansion of our universe--has consumed astronomers.
Our Antimatter, Mirrored, Time-Reversed Universe
13:50
The foundations of quantum theory rests on its symmetries.
Are Dark Matter And Dark Energy The Same?
13:08
Astronomers are the worst at naming things. Dark energy AND dark matter?
Why String Theory is Wrong
15:07
Why String Theory is Wrong
Quantum Physics in a Mirror Universe
12:18
What you think is a perfect reflection might be universe that is fundamentally different.
Did Life on Earth Come from Space?
14:20
Did life on Earth originate on another planet?
'Oumuamua Is Not Aliens
13:04
It’s never aliens … until it is. So let’s talk about ‘oumuamua.
Are Virtual Particles A New Layer of Reality?
13:43
Let me tell you a story about virtual particles. It may or may not be true.
Why String Theory is Right
13:37
Some see string theory as the one great hope for a theory of everything.
Supersymmetric Particle Found?
12:07
Supersymmetric Particle Found?
Will We Ever Find Alien Life?
12:44
Recent surveys draw scientific conclusions about the persistent absence of aliens.
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