"The Fabric of the Cosmos," a four-hour series based on the book by renowned physicist and author Brian Greene, takes us to the frontiers of physics to see how scientists are piecing together the most complete picture yet of space, time, and the universe. With each step, audiences will discover that just beneath the surface of our everyday experience lies a world we'd hardly recognize—a startling world far stranger and more wondrous than anyone expected.Brian Greene is going to let you in on a secret: We've all been deceived. Our perceptions of time and space have led us astray. Much of what we thought we knew about our universe—that the past has already happened and the future is yet to be, that space is just an empty void, that our universe is the only universe that exists—just might be wrong.Interweaving provocative theories, experiments, and stories with crystal-clear explanations and imaginative metaphors like those that defined the groundbreaking and highly acclaimed series "The Elegant Universe," "The Fabric of the Cosmos" aims to be the most compelling, visual, and comprehensive picture of modern physics ever seen on television.

Acclaimed physicist Brian Greene reveals a mind-boggling reality beneath the surface of our everyday world.

The Fabric of the Cosmos

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Black holes are the most enigmatic and exotic objects in the universe. They’re also the most powerful, with gravity so strong it can trap light. And they’re destructive, swallowing entire planets, even giant stars. Anything that falls into them vanishes…gone forever. Now, astrophysicists are realizing that black holes may be essential to how our universe evolved—their influence possibly leading to life on Earth and, ultimately, us. In this two-hour special, astrophysicist and author Janna Levin takes viewers on a journey to the frontiers of black hole science. Along the way, we meet leading astronomers and physicists on the verge of finding new answers to provocative questions about these shadowy monsters: Where do they come from? What’s inside? What happens if you fall into one? And what can they tell us about the nature of space, time, and gravity? (Premiered January 10, 2018)

Take a mind-blowing voyage to the most powerful and mysterious objects in the universe.

Black Hole Apocalypse

Particles of Thought: Bob and Mike’s Big Idea

Has science been missing a fundamental law of nature for centuries?

How Einstein Changed the Way We Understand Gravity

In 1912, Albert Einstein had a revolutionary idea: what if gravity wasn’t a force at all, but the result of warped space and time?
To understand gravity, Einstein had to rethink space and time as a single connected fabric. He showed that mass bends this fabric, guiding how everything moves.
How Einstein Changed the Way We Understand GravityPublished: July 28, 2025NARRATOR: In 1912, Einstein is living in Zurich with his wife, Mileva and two young sons, Hans and Eduard. The academic world had realized the importance of special relativity and his career had taken off. He&#x27;s now a professor at the esteemed Swiss Federal Institute of Technology, but spends as much time as possible working on his theory. He needs mathematics that describes how objects move in space and time, and soon realizes that the best tool for the job is a strange but powerful concept called space-time.JANNA LEVIN: If I think of space, I know that I can find anything if I know where it is, north, south, east, west, and up down three points, but that doesn&#x27;t mean I can find it because I also have to know where it is in time. And so if we start to think, &quot;To know everything about an event in the universe, I have to know not just its spatial coordinates, but also its time coordinate,&quot; I can begin to think about where it is in space-time.NARRATOR: Imagine a camera filming an action, capturing each moment in time as a single frame.ROBBERT DIJKGRAFF: Einstein basically tells us, &quot;Think of the movie reel.&quot; So you have all these little pictures. Now cut them apart one by one and stack them on top of each other. You get this pile, and if you go up in the pile, you go up in time. And now kind of glue them all together into one big block, and that block has both space and time, and that&#x27;s the space-time continuum.It&#x27;s almost looking at the movie not frame by frame, but seeing the whole movie at once. They would now be kind of two strands going up in space and time, and they would be kind of spaghetti strands. In fact, we all are spaghetti strands moving in this space-time.NARRATOR: Einstein feels that space-time is the natural arena in which his theory of relativity should play out, but now he needs sophisticated mathematics.SEAN CARROLL: By your standard or mine, Einstein was good at math. He was Einstein, but he was not really a mathematician per se. He didn&#x27;t prove theorems, he didn&#x27;t pour over math books. He was a physicist. He did thought experiments. He thought of very tangible, concrete situations and what would happen. So when it came time for him to really bear down to the absolute cutting-edge mathematics of his day, he required help.NARRATOR: At university, Einstein had skipped the geometry classes, letting his friend Marcel Grossmann take notes for him. Grossmann had excelled in geometry and was now chairman of the math department. He suggests Einstein uses advanced mathematics in which the shape of space and time could be curved.SEAN CARROLL: Because space-time has a geometry, he thinks to himself, &quot;Well, maybe it&#x27;s the actual shape of space-time itself that is giving rise to gravity.&quot;NARRATOR: After months of work, Einstein has an extraordinary idea. What if space-time is shaped by matter, and that&#x27;s what we feel as gravity?CLIFFORD JOHNSON: In struggling to figure out what causes gravity then, Einstein has this great insight. It is simply that a mass distorts the shape of space-time around it. So we get rid of this force of gravity, and instead we have curvature of space-time.SEAN CARROLL: In Einstein&#x27;s universe then, if space were empty, it would be flat. There&#x27;d be nothing going on. But as soon as you put objects down, they warp the space and time around them, and that causes a deviation of the geometry so that now things start moving.ROBBERT DIJKGRAFF: Everything wants to move as simple as possible through space and time, but Einstein tells us that mass sculpts space and time, and it&#x27;s the curved motion through this sculpture as the force of gravity.ELEANOR KNOX: We have this feeling that the reason I can feel pressure on the soles of my feet, that the reason things are going to drop when I throw them are because there&#x27;s a force attracting us down to the center of the Earth. What general relativity tells you is that&#x27;s not the right way to think about what&#x27;s going on there. What&#x27;s really going on is that your natural path in space-time would take you to the center of the Earth, and what&#x27;s actually happening is the floor is getting in the way. It&#x27;s pushing you upwards.SEAN CARROLL: We look at it, we go, &quot;Ah, the force of gravity,&quot; but Einstein says, &quot;no, no, no, the curvature of space-time.&quot;

In 1912, Albert Einstein had a revolutionary idea: what if gravity wasn’t a force at all, but the result of warped space and time?

Einstein's Thought Experiment That Transformed Physics

The faster you move, the stranger time becomes.
By imagining how light travels to two people moving at different speeds, Einstein showed that time isn’t absolute. His thought experiment revealed that what seems like “now” depends on where you are and how fast you’re moving.
Einstein&#x27;s Thought Experiment That Transformed PhysicsPublished: July 28, 2025NARRATOR: There&#x27;s a man standing on a railway platform. Two bolts of lightning strike on either side of him. The man is standing exactly halfway between them, and the light from each strike reaches his eyes at exactly the same moment. For him, the two strikes are simultaneous.Then, Einstein imagines a woman on a fast-moving train, traveling at close to the speed of light. What would she see? As the light travels out from the strikes, the train is moving towards one and away from the other. Light from the front strike reaches her eyes first. For the woman on the train, time elapses between the two strikes. For the man on the platform, there is no time between the strikes. This simple thought has mind-blowing significance. Simultaneity and the flow of time itself depends on how you are moving.SEAN CARROLL: Sean Carroll: If there&#x27;s no such thing as simultaneity, then there&#x27;s no such thing as absolute time everywhere throughout the universe and Isaac Newton was wrong.NARRATOR: This concept that time and space as well, are relative, became known as special relativity. It led to remarkable results such as the famous equation relating energy to mass.

The faster you move, the stranger time becomes.

How Music is Made Up of Math

Pythagoras saw a connection between math, music, and nature.
Hear a jazz musician explain how an octave, fifth, and fourth relate to math.
How Music is Made Up of MathPublished: May 19, 2025NARRATOR: The ancient Greeks found three relationships between notes especially pleasing. Now we call them an octave, a fifth, and a fourth.ESPERANZA SPALDING: An octave is easy to remember because it&#x27;s the first two notes of &quot;Somewhere Over the Rainbow.&quot; A fifth sounds like this, or the first two notes of &quot;Twinkle, Twinkle Little Star.&quot; And a fourth sounds like... You can think of it as the first two notes of &quot;Here Comes the Bride.&quot;NARRATOR: In the sixth century BCE, the Greek philosopher Pythagoras is said to have discovered that those beautiful musical relationships were also beautiful mathematical relationships by measuring the lengths of the vibrating strings. In an octave, the string lengths create a ratio of two to one. In a fifth, the ratio is three to two, and in a fourth, it is four to three.ESPERANZA SPALDING: Seeing a common pattern throughout sound, that could be a big eye-opener of saying, &quot;Well, if this exists in sound, and if it&#x27;s true, universally through all sounds, this ratio could exist universally everywhere, right?&quot; And doesn&#x27;t it?NARRATOR: Pythagoreans worship the idea of numbers. The fact that simple ratios produced harmonious sounds was proof of a hidden order in the natural world, and that order was made of numbers, a profound insight that mathematicians and scientists continue to explore to this day.

Pythagoras saw a connection between math, music, and nature.

An illustration of an atom and passing photons

Why is Laser Light Special?

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Explore how atomic structure and quantized energy levels are related to lasers with this video from NOVA Decoding the Universe: Quantum.

Do Plants Know Math?

Evolution seems to favor these numbers.
From the petals of flowers to spirals of pinecones, the Fibonacci sequence mysteriously shows up in nature.
Do Plants Know Math?Published: April 8, 2025Narrator: These may sound like random numbers, but they&#x27;re all part of what is known as the Fibonacci sequence, a series of numbers developed by a 13th century mathematician.&#x27;Mario Livio: You start with the numbers one and one, and from that point on, you keep adding up the last two numbers. So one plus one is two, now one plus two is three. Two plus three is five. Three plus five is eight, and you keep going like this, five plus eight.Narrator: Today, hundreds of years later, this seemingly arbitrary progression of numbers fascinates many who see in it clues to everything from human beauty to the stock market. While most of those claims remain unproven, it is curious how evolution seems to favor these numbers.Mario Livio: And as it turns out, I mean the sequence appears quite frequently in nature.Narrator: Fibonacci numbers show up in petal counts, especially of daisies, but that&#x27;s just a start.Christophe Golé: Statistically, the Fibonacci numbers do appear a lot in botany. For instance, if you look at the bottom of a pine cone, you will see often spirals in their scales. You end up counting those spirals. You&#x27;ll usually find a Fibonacci number, and then you will count the spirals going in the other direction, and you will find an adjacent Fibonacci number.Narrator: The same is true of the seeds on a sunflower head. Two sets of spirals, and if you count the spirals in each direction, both are Fibonacci numbers. While there are some theories explaining the Fibonacci botany connection, it still raises some intriguing questions.Christophe Golé: So do plants know math? The short answer to that is no. They don&#x27;t need to know math. In a very simple, geometric way they set up a little machine that creates the Fibonacci sequence in many cases.

Evolution seems to favor these numbers.

Do Aliens Exist? This Famous Equation Offers a Clue

The Drake Equation helps scientists estimate the odds of finding intelligent alien civilizations.
It’s an age-old question: Do aliens exist? And what are the odds we’ll make contact? A famous mathematical equation, known as the Drake Equation, helps scientists estimate the odds of finding intelligent alien civilizations, but new discoveries and unknown factors could change everything.
Do Aliens Exist? This Famous Equation Offers a CluePublished: March 14, 2025Athena Brensberger: Is there anyone out there? Hello? It&#x27;s an age-old question, do aliens exist? And what are the odds that we will make contact? There&#x27;s actually a famous mathematical equation that could help. The Drake Equation is used to help calculate the odds that advance alien civilizations exist in our galaxy. Over the years, scientists have proposed ways to update it, to reflect new discoveries like exoplanets and get closer to answering the questions are we alone and will we ever know for sure? So N in the equation stands for a specific kind of advanced alien civilization. Those that have the technology to produce radio signals detectable by earth. But there may be civilizations out there that don&#x27;t communicate with radio waves like we do here on Earth, or maybe they are just so far away that we can&#x27;t detect their signals. Then on the other side of the equation are all of the ingredients for advanced civilizations as we understand them.R star is the average rate that star suitable for the development of intelligent life form in our galaxy, and F sub P is the fraction of those stars that have planets around them. This number has been updated in the last couple of decades with the discovery of exoplanets, but for now, the rest of the terms are estimates, impossible to measure because we just really don&#x27;t know how many other planets have life, let alone intelligent, advanced life. So if most of these terms are estimates, then there&#x27;s no definitive answer to the Drake Equation. So why is this equation useful? Well, because it&#x27;s a framework. We have to start somewhere. It&#x27;s like a guideline for researchers to know what to look for and what to study to find life beyond earth. But one of the key pieces scientists really do wrestle with is the number of planets where life could become intelligent.That&#x27;s F sub I in the equation, and here&#x27;s why. The Drake Equation assumes that simple forms of life, like microbes inevitably evolve into complex and intelligent life. But others think that the jump in evolution from single celled organisms to intelligent life is not inevitable. And some even think that an important factor for how life on earth evolved to become intelligent and technologically advanced might have to do with something you probably learned about in grade school, plate tectonics, oceans, and continents. They argue that these things are so important that new terms should be added to the Drake Equation. But why? What do plate tectonics have to do with the evolution of advanced civilizations? Today, Earth&#x27;s crust is made up of massive plates that sit on top of the hot molten rock mantle. But billions of years ago, there was just one massive plate that broke apart as the mantle heated and cooled, forming mountains and volcanoes, creating diverse habitats, recycling nutrients, and regulating the climate.The movement of these plates is known as plate tectonics, and some scientists think that complex organisms on earth emerged on the ocean floor not long after plate tectonics started. Some researchers think those factors made it possible for life to evolve from the sea to the land, which was key for intelligent life developing technology. But at least so far, we don&#x27;t know of any other planets that have plate tectonics like we have here on earth. So factoring that into the Drake Equation dramatically lowers the odds of other advanced alien civilizations. By that calculation, we may be the only advanced civilization in the galaxy, but there&#x27;s a lot we don&#x27;t know about how life evolved to become intelligent. We really only have one example to study, earth.It may be that there are factors that we haven&#x27;t even thought to consider yet, totally unrelated to plate tectonics, and actually that&#x27;s a limitation of this whole thought experiment. We just can&#x27;t account for things we haven&#x27;t even thought to consider. But maybe one day the researchers listening for extraterrestrials will hear something, and if so, hopefully whoever is out there will live long enough for us to make contact.Ever hear the Fermi paradox? It may be that it takes so long for any kind of signal to travel to us or vice versa, that the civilization on the other end may no longer exist to receive it.Speaker 2:You&#x27;ve got-Athena Brensberger:And that&#x27;s L in the Drake Equation, the average length of time civilizations exist to make such signals. So what do you think? Are we alone? Does the Drake Equation need a revision? Will we ever find the aliens?

The Drake Equation helps scientists estimate the odds of finding intelligent alien civilizations.

Topic: Physics & Math

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