Is the moon really there when no one looks? It’s a question famously posed by Albert Einstein when thinking about paradoxes of quantum theory. Jonathan Halliwell breaks it down in the latest episode of The Joy of Why:

Events occurring in neurons’ extended branches, known as dendrites, can perform incredibly complex computations, sometimes as powerfully as a deep artificial neural network.

Ctenophores are considered “immortal jellyfish:” they have the Benjamin Button–like ability to reverse their development in the face of prolonged starvation or injury.

In the 1970s, the four-color theorem was controversially solved with the help of computers. A new algorithm produced this year has improved it in some interesting ways that offer new insights into the nature of graphs. Get the full story on The Quanta Podcast:

Comb jellies are ancient marine predators whose hairlike extensions known as cilia refract light as they swim, giving them an iridescent shimmer. They are the largest animals known to use cilia for movement.

A year ago this week, an unusual collection of mathematicians, philosophers, historians, and social scientists gathered in Leiden, home to the oldest university in the Netherlands, to ponder how artificial intelligence was changing math. Since then, a lot has changed. Konstantin Kakaes reports on Transformation:

“There’s always new perspectives coming along. The next generation of scientists will have new ways of thinking about these things.” Tune into this week’s episode of The Joy of Why:

As a grad student, the biologist Yitzhi “Patrick” Cai helped program 𝘌. 𝘤𝘰𝘭𝘪 bacteria to become a biosensor for arsenic contamination in drinking water. Today, he is leading a global effort to build the first-ever synthetic eukaryotic genome.

What are those little red dots? In a paper posted last week, astronomers described them as a snapshot of the births of supermassive black holes inside the cores of colossal stars. But not everyone agrees with this bold interpretation.

The Navier-Stokes equations are among the most important — and most challenging — equations in physics. So, what makes them so difficult? And how could a new OpenAI proof finally resolve the problem? Watch our new video:

In the 1960s, Christopher Zeeman helped popularize catastrophe theory. It was all the rage; people called on it to describe everything from bridge collapses to prison riots to regime changes. The hype soon fizzled. But the underlying concepts didn’t.

“For many years, Erdős was like a voice in the wilderness,” said New York University mathematician Joel Spencer. “He was getting these amazing results using randomness, and people had never done that before.”

Around 700 million years ago, a group of organisms resembling little more than glowing, gelatinous blobs split off from the rest of the animals, forming possibly the earliest branching animal lineage. Nearly 200 species of ctenophores, commonly known as comb jellies (but unrelated to jellyfish), live today in environments ranging from the cold depths of the sea to warm coastal surface waters. Their magic isn’t just in their persistence or iridescence; it’s in their DNA. Recently, ctenophores have helped answer long-standing questions about fundamental biology, from how early nervous systems evolved to the origins of the mesmerizing phenomenon of bioluminescence. For more than a century, scientists thought that sponges, or porifera, were the first to branch off — the sister group to all other animals. But over the past two decades, evidence has emerged that ctenophores were earlier. In 2023 — after years of a “ping-pong game” between labs debating which group came first, said evolutionary biologist Paul Burkhardt — a landmark paper analyzing chromosome organization found that ctenophores, not sponges, are the sister group, though this is yet to be fully settled. What makes this all the more surprising is that sponges lack muscles and neurons, while ctenophores have muscles and exhibit evidence of a simple nervous system. “If you think about the earliest branching animal lineage, you would expect less complexity,” Burkhardt said. “That changes a lot of the assumptions [about] how the very first animal may have looked.” The more researchers investigate comb jellies, the more complex they appear and the more we learn about the origins of animal life. 🪼 Explore the full gallery:

In the latest episode of The Joy of Why, Jonathan Halliwell explains how quantum decoherence is key to understanding how we transition from the wave-like behavior of the subatomic world to the classical macroscopic world that we’re used to. 🎧 Listen: