Join mathematician Professor Hannah Fry and science creator Michael Stevens (Vsauce) as they dig into the weird scientific questions that often go unexplored.
Welcome to The Rest Is Science, a show that sits in the fascinating space between what we think we know, and what we actually know. Why do we assume we understand things like time, randomness, or even gravity? Once you start questioning these familiar ideas, reality becomes astonishingly strange and completely fragile.
Whether you're a lifelong science fan or just naturally curious, The Rest Is Science will change your perception of reality, and prove that the biggest questions are always the most fun.
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Have you stubbed your toe and shouted an unrepeatable word? Isaac Newton and Robert Boyle were two of the greatest minds in humanity. Did their egos and competition with one another hold them back or drive them onto huge breakthroughs? Professor Hannah Fry and Michael Stevens explore the bizarre neurology of vocalised pain, revealing how a good yelp actually acts as a biological off-switch for suffering and unearth if Newton was the biggest crybaby in science. Plus, Hannah gives us a behind-the-...
Botanically speaking, there is no such thing as a vegetable, so what exactly is sitting on your dinner plate? And if our culinary world is built on biological lies, which plant is actually the most vegetable like? Professor Hannah Fry and Michael Stevens tackle a chaotic intersection of linguistics, plant taxonomy, and nutrition, dismantling the arbitrary categories we use to organise our food, revealing that our supermarket aisles are a scientifically lawless wasteland. It is a strangely profou...
Does your native language physically sculpt your face? And could a swarm of bees be trained to run computer code? Two of your questions answer in this Field Notes with Professor Hannah Fry and YouTube's Michael Stevens, plus Michael’s object of the week is a visualization of the Holocene Calendar. By simply adding ten thousand years to our current year, it transforms our perception of history from a brief modern blip into an unbroken, monumental narrative of human progress. Check out the calenda...
Humans have split the atom, we can stream movies from space and are working towards everlasting life. So why in the world are we still spending a third of our lives unconscious? In this episode of The Rest Is Science, Hannah Fry and Michael Stevens ask a deceptively simple question: Can human beings cure sleep? Why do evolutionary forces cause us to lie helpless for eight hours a night when predators might lurk? Why can elephants survive on two hours but bats basically exist to nap? And what rea...
Rockets are built to slice cleanly through the atmosphere on the way up. Coming home, it turns out, requires... not turning into a fireball before a bellyflop When Space Shuttles reenter Earth’s atmosphere at 17,000 miles per hour, they don’t dive nose first. Instead they turn broadside to the atmosphere, deliberately creating more drag, more friction, more heat. At those speeds, oncoming air compresses into a shockwave hotter than molten lava. In this episode of Field Notes, Professor Hannah Fr...
If someone asked you to point to yourself, where would you point? Your chest? Your head? Somewhere just behind your eyes? Where are you? In this episode, Professor Hannah Fry and VSauce’s Michael Stevens explore how the brain maps and understands out location, from the inner ear fluid that tells us which way is up, to the grid and place cells that build a kind of internal GPS. But how do London taxi drivers rewire their brains to memorise entire cities when the rest of us can’t? How does languag...
At what exact chemical ratio does our beloved chocolate devolve into a mere structure of fats and sugars? How far can you dilute chocolate before its fundamental identity vanishes? And what could a comically tiny novelty stool possibly reveal about Michael Stevens? Unlike a block of pure iron or a vial of chlorine, chocolate is not one single substance but a complex and heterogeneous mixture we all take for granted. Hannah and Michael explore the chemistry and nutritional boundaries of this ever...
Is deception a uniquely human trait, or is the natural world built on a foundation of fraud? When a cuttlefish shifts its skin to mimic a female and sneak past a rival male, this may be deceptive but is it telling a lie? Professor Hannah Fry and VSauce's Michael Stevens explore the evolutionary biology of dishonesty across the animal kingdom. What is the neurological difference between a biological reflex and a calculated bluff? What kind of cognitive processing is needed for true artifice, and ...
Topologically speaking, a human is just a donut with seven holes. It sounds like a joke, but it is a fundamental biological reality. Professor Hannah Fry and Michael Stevens explore the strange geometry of the human body, tracing how we evolved from simple tubes into complex toruses. They investigate the "design flaw" at the boundary of our existence, the fragile transition where skin meets internal lining, and ask why nature built us with so many vulnerabilities to the outside world. But before...
It starts as a friendly challenge: who can name the biggest number? The only rule? Infinity doesn’t count. What follows is a journey through the biggest finite numbers ever imagined. From Archimedes’ grains of sand to Graham’s Number, a sequence so vast it stretches the limits of human comprehension, Professor Hannah Fry and Michael Stevens tumble through this strange landscape of scale, tracing how mathematicians have pushed counting to its absolute edge. But beyond vast calculations, perhaps t...
Can mathematics ever truly be proven? And can Michael's poetry help you remember some tricky equations? In this episode, Professor Hannah Fry and Michael Stevens answer your questions and take a look at what it means for something to be true in mathematics. Starting with a grand attempt to prove that one plus one equals two, and into Gödel’s theorem that no system of maths can ever fully prove itself, they explore how maths connects to the real world, from an equation that predicts antimatter to...
Is it possible to make a sport too good? Professor Hannah Fry and Michael Stevens explore how science, data, and optimisation are transforming modern sports improving athletes and teams, while quietly changing how games are played, watched, and understood. From the Tush Push in the NFL and defensive shifts in Major League Baseball, to dirty air in Formula 1, expected goals in Premier League football, and the statistical dominance of seven footers in the NBA, they examine how prediction, probabil...
Hannah Fry and Michael Stevens explore scientific oddities, from the counter-intuitive nature of mirror reflections to the extreme physics of creating a black hole from a hamster. They also debunk the popular myth about Earth's smoothness compared to a pool ball, revealing the planet's true texture. The episode concludes with a fascinating discussion on fulgurites, natural glass formed by lightning, and the man-made equivalent, Trinitite, delving into the unexpected ways science shapes our understanding of scale and matter.
Professor Hannah Fry and Michael Stevens explore boredom not as laziness, but as a crucial brain signal indicating a lack of new information or meaning. They discuss experiments from dopamine studies in monkeys to sensory deprivation and solitary confinement, showing how the mind seeks stimulation, even resorting to self-inflicted discomfort or hallucinations. Ultimately, the episode reframes boredom as an evolutionary driver essential for human innovation and exploration, rather than a mere negative experience.
Can we store summer’s heat to warm our homes in winter? Could humans perceive a fourth dimension? And why does light bend around gravity even though it has no mass? Small questions from YOU which open doors to enormous worlds. In this episode of Field Notes, Hannah Fry and Michael Stevens discuss underground heat batteries in Canada and Einstein’s thought experiments, from how the universe hides its secrets and how we uncover them. Later, Michael presents a story which leads to an exploration of...
What do we mean when we call an event random? Most people view randomness as a fundamental property of the universe, but is it just a label for our own lack of knowledge? Whether it is a weighted coin toss, a scratch card, or the digits of Pi, unpredictability usually emerges from rules and patterns that sit just beyond our perception. Professor Hannah Fry and Michael Stevens dismantle the logic of chance, exploring how chaos is governed by strict mathematical laws and why a coin can be '50 / 50...
Some objects feel like they’re from another world. One of these might be the giant structure that makes up a quantum computer. Lifted straight from the TV series Devs, Professor Hannah Fry shows Michael Stevens a prop that was designed to look just like one…now it hangs from the ceiling in her house. In this episode of Field Notes, Hannah and Michael examine the extraordinary technology behind of quantum computing. They explore how qubits differ from classical bits and consider the ways this tec...
Right now, you’re breathing in. As you inhale, air rushes past millions of sensory receptors, activating the part of your brain responsible for smell. And yet, there’s one scent you’ll never notice: the very nose you’re breathing through, because humans are smell blind to themselves. Today, Professor Hannah Fry and VSauce's Michael Stevens explore the mechanics of perinasal chemosensation, otherwise known as smell. They explore how the Victorians sidelined the sense, why we’ve underestimated it ...
Hannah and Michael delve into the captivating world of acoustic levitation, demonstrating how precisely tuned sound waves can suspend objects and discussing its futuristic applications in medicine, such as targeted drug delivery and internal body exploration. They also tackle listener questions, comparing human swimming prowess to various shark species and debating the impact of technology on athletic performance. The episode concludes with a creative discussion on inventing scientifically fascinating yet impractical machines, highlighted by the historic Pitch Drop experiment.
Hannah Fry and Michael Stevens delve into the perplexing world of magnetism, discussing how Earth generates its protective magnetic field through a molten core and why its poles periodically flip. They explore the fascinating ways various animals, from robins seeing magnetic 'glows' to whales navigating oceans, sense this field, often getting disrupted by solar events. The hosts also consider whether humans possess a vestigial ability to detect magnetism, ultimately concluding that our curiosity has driven us to understand and utilize this fundamental force, transforming it from a 'magic' into a scientific marvel.
This 'Field Notes' episode dives into unexpected scientific curiosities, beginning with a lively debate on 'math' versus 'maths.' The hosts then explore the physics of crowd dynamics, from mosh pits as fluid systems to counterintuitive safety designs using granular flow. Michael also showcases his extensive dice collection, delving into their mathematical fairness, the art of cheating dice, and the unique geometry of polyhedrons. The discussion culminates with the history and importance of genuinely random numbers and mathematical constants like Pi.
Hosts Hannah Fry and Michael Stevens explore the surprisingly arbitrary nature of our calendar and time. They trace the errors in the Julian calendar, Pope Gregory XIII's controversial 10-day jump, and the resistance to his reforms. The discussion also covers the administrative origins of New Year's Day, how travel necessitated time standardization, and the incredible precision of atomic clocks, ultimately questioning how we'll keep time across the solar system.
This festive "Field Notes" episode uncovers the true nature of Christmas tree smell, explaining how the comforting pine scent is actually a tree's chemical warning system and an evolutionary strategy for survival through fire. Additionally, hosts Michael and Hannah guide listeners through intriguing tactile illusions, like the upside-down tongue and crossed fingers, demonstrating the brain's remarkable yet sometimes inaccurate sensory mapping and its incredible plasticity, even discussing phantom limbs and sensory re-mapping experiments.
Hannah Fry and Michael Stevens delve into the logistical challenge of Santa Claus delivering presents worldwide in a single night, stripping away magic. They investigate historical population bottlenecks, the geographical spread of early Homo sapiens, and hypothetical prehistoric transportation methods. The discussion also covers the origins of St. Nicholas and what gifts a non-magical, prehistoric Santa might have distributed, from shell beads to miniature hand axes and early forms of beer.
Hannah and Michael delve into the elegance of an ellipsograph, a mechanical tool for drawing perfect ellipses, and the historical resistance to accepting elliptical planetary orbits, championed by Kepler. They showcase an orrery calendar illustrating planetary movements and demonstrate CMY color cubes, explaining subtractive color mixing. The hosts also answer listener questions, discussing dream dinner guests from the scientific past and debunking common misconceptions about goldfish memory.
Hannah Fry and Michael Stevens investigate the surprising truth behind the phrase "we're made of stars," revealing that tiny particles like beryllium and boron have non-stellar origins from cosmic ray spallation. The discussion then expands to the nature of cosmic rays, their detection, and profound real-world impacts, from creating high-energy "Oh My God" particles to causing glitches in pacemakers, airplanes, and even a Super Mario speedrun. The episode concludes by explaining how these invisible particles are essential for radiocarbon dating and human evolution.
What makes a simple brain-teaser about two identical swords one of the most deceptively tricky logic puzzles of the last century? And why has this seemingly innocent riddle fascinated mathematicians, programmers and puzzle-solvers for decades? First shared in recreational maths circles before spreading across classrooms and online forums, the “swords of truth” puzzle asks a disarmingly straightforward question — yet its solution reveals deep ideas about reasoning, information, and the limits of ...
Has music really been getting worse… or is it just shifting in ways we don’t always notice? And why does the soundtrack to your teenage years feel like the single greatest playlist ever made? Hannah and Michael explore music’s strange grip on our minds. They trace why certain lyrics feel simpler than they used to, and what gives our formative songs lasting emotional charge. And what exactly is the reminiscence bump, that curious memory quirk that makes certain songs feel unforgettable? Join Hann...
How did pages of mysterious “gibberish” sent from Madras find their way to one of Cambridge University’s most respected mathematicians? Were the strange formulas the work of a deluded mind - or breakthrough insights of an unknown genius? The author of that letter was Srinivasa Ramanujan. His story inspired two Hollywood blockbusters (Goodwill Hunting, The Man Who Knew Infinity) but his mind changed the shape of mathematics forever. Welcome to The Rest Is Science: Field Notes. Every Thursday, Han...
Are humans the only creatures that shed emotional tears? If we are, what purpose do these tears really serve? If crying is so natural, why do we so often try to hide it? A single sob sends Hannah and Michael into an unexpected journey through the science and mystery of emotional crying, from the first tearful moments of infancy to the complex social signals behind adult weeping. Why do babies cry before they can speak? How do tears strengthen - or strain - our relationships? And what is the horm...
