In keeping with the theme of TED2008, professor Stephen Hawking asks some Big Questions about our universe -- How did the universe begin? How did life begin? Are we alone? -- and discusses how we might go about answering them.

With his art, photographer Platon seeks to strip away assumptions and leave viewers with a window into his subject's character, filling our eyes with wonder and curiosity. Sharing extraordinary stories of what it's like to photograph some of the world's most prominent figures -- from Michelle Obama and Pussy Riot to Vladimir Putin and Muhammad A...

X Prize founder Peter Diamandis talks about how he helped Stephen Hawking fulfill his dream of going to space -- by flying together into the upper atmosphere and experiencing weightlessness at zero g.

Many of those with severe speech disorders use a computerized device to communicate. Yet they choose between only a few voice options. That's why Stephen Hawking has an American accent, and why many people end up with the same voice, often to incongruous effect. Speech scientist Rupal Patel wanted to do something about this, and in this wonderfu...

Black holes are among the most destructive objects in the universe. Anything that gets too close to a black hole, be it an asteroid, planet, or star, risks being torn apart by its extreme gravitational field. By some accounts, the universe may eventually consist entirely of black holes. But is there any way to destroy a black hole? Fabio Pacucci...

Today, one of the biggest paradoxes in the universe threatens to unravel modern science: the black hole information paradox. Every object in the universe is composed of particles with unique quantum properties and even if an object is destroyed, its quantum information is never permanently deleted. But what happens to that information when an ob...

The nerve disease ALS left graffiti artist TEMPT paralyzed from head to toe, forced to communicate blink by blink. In a remarkable talk at TEDActive, entrepreneur Mick Ebeling shares how he and a team of collaborators built an open-source invention that gave the artist -- and gives others in his circumstance -- the means to make art again.

Designer Jared Ficklin creates wild visualizations that let us see music, using color and even fire (a first for the TED stage) to analyze how sound makes us feel. He takes a brief digression to analyze the sound of a skatepark -- and how audio can clue us in to developing creativity.

The fact that no one knows the answer to this question is what makes it exciting. The story of physics has been one of an ever-expanding understanding of the sheer scale of reality, to the point where physicists are now postulating that there may be far more universes than just our own. Chris Anderson explores the thrilling implications of this ...

Why is there something instead of nothing? In other words: Why does the universe exist (and why are we in it)? Philosopher and writer Jim Holt follows this question toward three possible answers. Or four. Or none.

Physicist Patricia Burchat sheds light on two basic ingredients of our universe: dark matter and dark energy. Comprising 96% of the universe between them, they can't be directly measured, but their influence is immense.

Accepting his 2008 TED Prize, physicist Neil Turok speaks out for talented young Africans starved of opportunity: by unlocking and nurturing the continent's creative potential, we can create a change in Africa's future.

Technology should work for us, but what happens when it doesn't? Comedian Chuck Nice explores the unintended consequences of technological advancement and human interaction -- with hilarious results.

As a research scientist at Google, Margaret Mitchell helps develop computers that can communicate about what they see and understand. She tells a cautionary tale about the gaps, blind spots and biases we subconsciously encode into AI -- and asks us to consider what the technology we create today will mean for tomorrow. "All that we see now is a ...

When your job hinges on how well you talk to people, you learn a lot about how to have conversations -- and that most of us don't converse very well. Celeste Headlee has worked as a radio host for decades, and she knows the ingredients of a great conversation: Honesty, brevity, clarity and a healthy amount of listening. In this insightful talk, ...

New tech spawns new anxieties, says scientist and philosopher Grady Booch, but we don't need to be afraid an all-powerful, unfeeling AI. Booch allays our worst (sci-fi induced) fears about superintelligent computers by explaining how we'll teach, not program, them to share our human values. Rather than worry about an unlikely existential threat,...

In the pitch-black night, stung by jellyfish, choking on salt water, singing to herself, hallucinating … Diana Nyad just kept on swimming. And that's how she finally achieved her lifetime goal as an athlete: an extreme 100-mile swim from Cuba to Florida -- at age 64. Hear her story.

TED curator Chris Anderson shares his obsession with questions that no one (yet) knows the answers to. A short intro leads into two questions: Why can't we see evidence of alien life? And how many universes are there?

Legendary scientist David Deutsch puts theoretical physics on the back burner to discuss a more urgent matter: the survival of our species. The first step toward solving global warming, he says, is to admit that we have a problem.

Despite multibillion-dollar investments in cybersecurity, one of its root problems has been largely ignored: who are the people who write malicious code? Underworld investigator Misha Glenny profiles several convicted coders from around the world and reaches a startling conclusion.

Computer science began in the '30s ... the 1830s. John Graham-Cumming tells the story of Charles Babbage's mechanical, steam-powered "analytical engine" and how Ada Lovelace, mathematician and daughter of Lord Byron, saw beyond its simple computational abilities to imagine the future of computers.

It starts with a sketch. Then it evolves into a larger-than-life visual masterpiece, a celebration of human connection. Follow along as legendary artist and designer Es Devlin takes us on a visual tour of her work -- including iconic stage sculptures she's created for Beyoncé, Adele, Kanye West, U2 and more -- and previews her design for the upc...

Cosmologist Sean Carroll attacks -- in an entertaining and thought-provoking tour through the nature of time and the universe -- a deceptively simple question: Why does time exist at all? The potential answers point to a surprising view of the nature of the universe, and our place in it.

Our consciousness is a fundamental aspect of our existence, says philosopher David Chalmers: “There’s nothing we know about more directly…. but at the same time it’s the most mysterious phenomenon in the universe.” He shares some ways to think about the movie playing in our heads.

How can we harness the power of superintelligent AI while also preventing the catastrophe of robotic takeover? As we move closer toward creating all-knowing machines, AI pioneer Stuart Russell is working on something a bit different: robots with uncertainty. Hear his vision for human-compatible AI that can solve problems using common sense, altr...

Richard Dawkins urges all atheists to openly state their position -- and to fight the incursion of the church into politics and science. A fiery, funny, powerful talk.

It can be easy to believe that humans are insignificant. We're specks of dust on a random planet in a vast universe. Less powerful than elephants. Fewer than ants. But David Deutsch believes that's all beside the point, because humans possess one unique skill: attaining knowledge. David Deutsch -- Oxford professor, father of quantum computing, r...