Many Worlds interpretation of quantum mechanics proposes that every time a quantum event gets decided, the universe splits so that every possible outcome really does occur. But where exactly are those worlds, and can we ever see them?

The moment you started observing reality, you hopelessly polluted any conclusions you might make about it. The anthropic principle guarantees that you are NOT seeing the universe in most typical state. But used correctly, this highly...

It was pretty impressive when LIGO detected gravitational waves from colliding black holes. Well we’ve just taken that to the next level with a galaxy-spanning gravitational wave detector that may have detected a foundational element of...

The great physicist Hermann Weyl once said: "My work always tried to unite the true with the beautiful, but when I had to choose one or the other, I usually chose the beautiful." But is this actually good advice for doing physics?

By the time you've read this, a billion billion dark matter particles may have streamed through your body like ghosts. The particle or particles of the dark sector make up the vast majority of the mass of the universe - so to them, we're...

Whenever we open a new window on the universe, we discover things that no one expected. Our newfound ability to measure ripples in the fabric of spacetime—gravitational waves—is a very new window, and so far we’ve seen a lot of wild...

If we ever want to simulate a universe, we should probably learn to simulate even a single atomic nucleus. But it’s taken some of the most incredible ingenuity of the past half-century to figure out how that out. All so that today I can...

Neils Bohr said, “It is wrong to think that the task of physics is to find out how Nature is. Physics concerns what we can say about Nature.” Well it turns out that if we pay attention to this subtle difference, some of the most...

If a photon leaves the train station shortly after the Big Bang ...

Hook up an old antenna to your TV and scan between channels. The static buzz you hear is mostly due to the ambient radio produced by our noisy pre-galactic civilization. But around one percent of that buzz is something very different –...

Every astronomy textbook tells us that soon after the Big Bang, there was a period of exponentially accelerating expansion called cosmic inflation. In a tiny fraction of a second, inflationary expansion multiplied the size of the...

The search for a single number: the hubble constant, which is the rate of expansion of our universe, has consumed astronomers for generations. Finally, two powerful and independent methods have refined its measurement to unprecedented...

Invisible to the naked eye, our night sky is scattered with the 100s of billions of galaxies the fill the known universe. Like the stars, these galaxies form constellations – hidden patterns that echo the reverberations of matter and...

The results are in - on this weeks episode of Spacetime we reveal the answer to our Asteroid Challenge, as well as our T-shirt winners! Check out who saved the world!

Do you want to major in Astrophysics? Are you thinking about becoming (or ever just wondered how one becomes) an Astrophysicists? Do you want to know Matt O’Dowd’s origin story? Then buckle up and enjoy the ride and try your astrophysics...

Our universe seems pretty complicated. We have a weird zoo of elementary particles, which interact through very different fundamental forces. But some extremely subtle clues in nature have led us to believe that the forces of nature were...

We humans have always been explorers. The great civilizations that have arisen across the world are owed to our restless ancestors. These days, there’s not much of Earth left to explore. But if we look up, there’s a whole universe out...

Our universe started with the big bang. But only for the right definition of “our universe”. And of “started” for that matter. In fact, probably the Big Bang is nothing like what you were taught.

A hundred years ago we discovered...

Now that we have a primer on the aspects of the Big Bang Theory that we know definitely happened, let’s look further into what we don’t yet know, and how the theory could progress in the future. Since there is a discrepancy between...

Recently, the oldest quasar ever seen was discovered by the Gemini North telescope in Hawaii, the Magellan Telescopes at Las Campanas Observatory in Chile, as well as the Large Binocular Telescope in Arizona. In this first episode of...

Causality is meant to move in one direction: forward. But the Quantum Eraser experiment seems to reverse causality. How and why can this happen and what are the implications of this experiment on how we understand Quantum Mechanics and...

Throughout history, there has been much speculation about what the fate of the universe would be. Many theorized that the universe would eventually succumb to the pull of gravity, and reverse its expansion in what was being called ‘The...

In astronomy we study things that are very far away. It’s a powerful challenge because even the brightest objects are almost impossibly faint when you view them from the other side of the universe. But there’s an up side. If the light...

Fast Radio Bursts were puzzling physicist for quite some time. They were thought to be the result of large cataclysmic events such as supernovae, but this theory was proven wrong when it was discovered that they could repeat themselves....