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The silence of the galaxy and the resulting Fermi Paradox has perplexed us for nearly 50 years. But our most recent surveys of the Milky Way finally allow us to draw scientific conclusions about the depressingly persistent absence of aliens.

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

Some see string theory as the one great hope for a theory of everything – that it will unite quantum mechanics and gravity and so unify all of physics into one glorious theory.

With the large hadron collider running out of places to look for clues to a deeper theory of physics, we need a bigger particle accelerator. We have one - the galaxy.

Higher dimensional spheres, or hyperspheres, are counter-intuitive and almost impossible to visualize. Mathematician Kelsey Houston-Edwards explains higher dimensional spheres and how recent revelations in sphere packing have exposed truths about 8 and 24 dimensions that we don't even understand in 4 dimensions.

Is math real or simply something made up by mathematicians? You can’t physically touch a number yet using numbers we’re able to build skyscrapers and launch rockets into space. Mathematician Kelsey Houston-Edwards explains this perplexing dilemma and discusses the different viewpoints that philosophers and mathematicians have regarding the realism of mathematics.

Do two people on the planet have the exact same number of body hairs? How about more than two? There’s a simple yet powerful mathematical principle that can help you find out the answer. Kelsey Houston-Edwards breaks down the Pigeonhole Principle and explains how it can be used to answer some pretty perplexing questions.

There are different sizes of infinity. It turns out that some are larger than others. Mathematician Kelsey Houston-Edwards breaks down what these different sizes are and where they belong in The Hierarchy of Infinities.

You’re about to throw a party with a thousand bottles of wine, but you just discovered that one bottle is poisoned! Can you determine exactly which one it is?

Mathematician Mark Kac asked the question “Can we hear the shape of a drum?” It was a question that took over 20 years to answer. Sine waves, fundamental frequencies, eigenvalues, this episode has got it all!

You’ve always been told that pi is 3.14. This is true, but this number is based on how we measure distance. Find out what happens to pi when we change the way we measure distance.

In this episode probability mathematics and chess collide. What is the average number of steps it would take before a randomly moving knight returned to its starting square?

Mathematician Kelsey Houston-Edwards explains exactly what singularities are and how they exist right under our noses.

We're back in Bozeman, Montana this week talking to Amy Atwater, Collections Manager at the Museum of the Rockies. MOR has among the largest collections of North American dinosaurs in the United States. We talk to Amy about her job and the collection she manages.

The search for our origins go back to a single common ancestor -- one that remains shrouded in mystery. It’s the ancestor of everything we know and today scientists call it the last universal common ancestor, or LUCA.

The ancestors of modern, squishy cephalopods like the octopus and the squid all had shells. In ancient times, their shell was their greatest asset but it eventually proved to be their biggest weakness.

Two extinct relatives of horses and rhinos are closely related to each other but have strikingly different body plans. How did two of the same kind of animal, living in the same place, end up looking so different?

Reptiles emerged from the Paleozoic as humble creatures, but in time, they grew to become some of the largest forms of life ever to stomp, swim, and soar across the planet. This Age of Reptiles was a spectacular prehistoric epic, and it all took place in a single era: the Mesozoic.

In 1912, a fossil collector discovered some strange bone fragments in the eerie, beautiful Cretaceous Bahariya rock formation of Egypt. Eventually, that handful of fossil fragments would reveal to scientists one of the strangest dinosaurs that ever existed -- the world’s only known semi-aquatic dinosaur.

After taking you on a journey through geologic time, we've arrived at the Cenozoic Era. Most of the mammals and birds that you can think of appeared during this era but perhaps more importantly, the Cenozoic marks the rise of organisms that look a lot like us.

At the beginning of the Triassic Period, with the continents locked together from pole-to-pole in the supercontinent of Pangea, the world is hot, flat, and very, very dry. But then 234 million years ago, the climate suddenly changed for the wetter.

The Triassic was full of creatures that look a lot like other, more modern species, even though they’re not closely related at all. The reason for this has to do with how evolution works and with the timing of the Triassic itself: when life was trapped between two mass extinctions.

There are fossils of viruses, of sorts, preserved in the DNA of the hosts that they’ve infected. Including you. This molecular fossil trail can help us understand where viruses came from, how they evolved and it can even help us tackle the biggest question of all: Are viruses alive?

385 million years ago, a group of fish would undertake one of the most important journeys in the history of life and become the first vertebrates to live on dry ground. But first, they had to acquire the ability to breathe air.

Tyrannosaurus rex was big, Tyrannosaurus rex was vicious, and Tyrannosaurus rex had tiny arms. The story of how T-Rex lost its arms is, itself, pretty simple. But the story of why it kept those little limbs, and how it used them? Well, that’s a little more complicated.