Air. I bet you never even notice that it’s there. Yet you are swimming in an ocean of it every day. If there’s a literal ton of air pressing down on you all the time, so why don’t we feel it? We look back at the history of physics to...

I don’t want to alarm you, but the world is going to end. All of this. Gone. And scientists are certain all of this will happen. On the bright side this isn’t going to happen for 4-5 billion years. It makes me wonder: In a universe...

Glass is made of sand, which is a kind of rock. But glass is transparent, and rocks aren’t transparent. What’s up with that? Why is glass clear? And why can I sit on a chair? And why can we touch anything? Today we zoom down to the weird...

Earth has seasons, but what about the rest of the planets in the solar system? Let’s take a tour from Mercury to Pluto and see what seasons would be like on all our planetary neighbors. Bring a sweater!

You have questions, I have answers.

You have questions, I have answers.

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....

We actually have a pretty good idea of what might have happened before the Big Bang. That is, as long as we define the Big Bang as the extremely hot, dense, rapidly expanding universe that is described by Einstein’s equations. That...

When we finally have a quantum internet you’ll be able to simultaneously like and dislike this video. But we don’t. So I hope you like it. The world is widely regarded as being well and truly into the digital age, also called the...

We’ve been failing to detect dark matter for decades. Finally, the latest failure to detect dark matter may have actually proved its existence. One of these is true: either most of the matter in the universe is invisible and formed of...

Have you ever asked “what is beyond the edge of the universe?” And have you ever been told that an infinite universe that has no edge? You were told wrong. In a sense. We can define a boundary to an infinite universe, at least...

The private space-race has been on for a while now. The attention has been on Space-X and Blue Origin with their reusable rockets. But there’s one private space program that’s been doing things a little differently. Richard Branson’s...

Challenge question: if 1kg of apples is $5 and 2kg is $10, how much is -1kg of apples? The answer? Priceless. Because you could use negative-mass apples to build warp drives, travel in time, and construct a perpetual motion machine. In...

On September 14th, 2015 LIGO announced the first detection of a gravitational wave. This was hailed at the time as the dawn of gravitational wave astronomy. However that’s only true if the we ever detect another gravitational wave. Now...

Scientists at the Large Hadron Collider may have just discovered a new fundamental particle that could change the way we look at the universe. Is this Dark Energy? A giant Neutrino? The big brother of the Higgs Boson? Or could it be the...

Space is big, and it’s getting bigger. But where does all that new space actually come from? And is it popping into existence all around you right now? Is that why the remote control is always further away than I thought?

This is a map of the multiverse. Or in physics-ese, it’s the maximally extended Penrose diagram of a Kerr spacetime. And in english: when you solve Einstein’s equations of general relativity for a rotating black hole, the universe does...

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There’s an absolute limit to our access to the universe beyond our own galaxy. There’s a limit to what we can ever hope to explore or send signals to, and a very different limit to what we can ever hope to witness. Today we’re going to...

Two protons next to each other in an atomic nucleus are repelling each other electromagnetically with enough force to lift a medium-sized labradoodle off the ground. Release this energy and you have, well, you have a nuclear explosion....

Perhaps you’ve seen videos of how the planets of the solar system move through the universe in this cool helix. Not only are these misleading, but the Earth’s real motion - YOUR motion through the universe, is way more complicated and...

Supercritical Fluids are one the strangest states of matter and yet they are found everywhere from Decaf Coffee, to dry cleaning, to the atmosphere of Jupiter. When we think of an exotic state of matter we tend to think of the really...

I’m going to tell you about the craziest proposal for an astrophysics mission that has a good chance of actually happening. A train of spacecraft sailing the sun’s light to a magical point out there in space where the Sun’s own gravity...

Black holes are very real, but are also a theoretical nightmare. It turns out that in order to make sense of their paradoxical nature, every black hole has to be thought of as a multitude of imaginary black holes, all connected by...