Season 5

Video thumbnail: PBS Space Time Perpetual Motion From Negative Mass?

PBS Space Time

Perpetual Motion From Negative Mass?

Challenge question: if 1kg of apples is $5 and 2kg is $10, how much is -1kg of apples?

Perpetual Motion From Negative Mass?

Video thumbnail: PBS Space Time The Crisis in Cosmology

PBS Space Time

The Crisis in Cosmology

The hubble constant--the rate of expansion of our universe--has consumed astronomers.

The Crisis in Cosmology

Video thumbnail: PBS Space Time Are Dark Matter And Dark Energy The Same?

PBS Space Time

Are Dark Matter And Dark Energy The Same?

Astronomers are the worst at naming things. Dark energy AND dark matter?

Are Dark Matter And Dark Energy The Same?

Video thumbnail: PBS Space Time 'Oumuamua Is Not Aliens

PBS Space Time

'Oumuamua Is Not Aliens

It’s never aliens … until it is. So let’s talk about ‘oumuamua.

'Oumuamua Is Not Aliens

Video thumbnail: PBS Space Time Are Virtual Particles A New Layer of Reality?

PBS Space Time

Are Virtual Particles A New Layer of Reality?

Let me tell you a story about virtual particles. It may or may not be true.

Are Virtual Particles A New Layer of Reality?

Video thumbnail: PBS Space Time Why String Theory is Right

PBS Space Time

Why String Theory is Right

Some see string theory as the one great hope for a theory of everything.

Why String Theory is Right