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Tag 'Physics'

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Stephen Hawking asks big questions about the universe

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.

Making sense of string theory

Physicist Brian Greene explains superstring theory, the idea that minscule strands of energy vibrating in 11 dimensions create every particle and force in the universe.

Why the universe seems so strange

Biologist Richard Dawkins makes a case for "thinking the improbable" by looking at how the human frame of reference limits our understanding of the universe.

Is our universe the only universe?

Is there more than one universe? In this visually rich, action-packed talk, Brian Greene shows how the unanswered questions of physics (starting with a big one: What caused the Big Bang?) have led to the theory that our own universe is just one of many in the "multiverse."

Boaz Almog “levitates” a superconductor

How can a super-thin 3-inch disk levitate something 70,000 times its own weight? In a riveting demonstration, Boaz Almog shows how a phenomenon known as quantum locking allows a superconductor disk to float over a magnetic rail -- completely frictionlessly and with zero energy loss. Experiment: Prof. Guy Deutscher, Mishael Azoulay, Boaz Almog, of the High Tc

Why our universe might exist on a knife-edge

The biggest surprise of discovering the Higgs boson? That there were no surprises. Gian Giudice talks us through a problem in theoretical physics: what if the Higgs field exists in an ultra-dense state that could mean the collapse of all atomic matter? With wit and charm, Giudice outlines a grim fate -- and why we shouldn't start worrying just yet. (Filmed at

George Smoot on the design of the universe

At Serious Play 2008, astrophysicist George Smoot shows stunning new images from deep-space surveys, and prods us to ponder how the cosmos -- with its giant webs of dark matter and mysterious gaping voids -- got built this way.

Computing a theory of everything

Stephen Wolfram, creator of Mathematica, talks about his quest to make all knowledge computational -- able to be searched, processed and manipulated. His new search engine, Wolfram Alpha, has no lesser goal than to model and explain the physics underlying the universe.

Comics that ask "what if?"

Web cartoonist Randall Munroe answers simple what-if questions ("what if you hit a baseball moving at the speed of light?") using math, physics, logic and deadpan humor. In this charming talk, a reader’s question about Google's data warehouse leads Munroe down a circuitous path to a hilariously over-detailed answer — in which, shhh, you might actually learn something.

A theory of everything

Physicist and surfer Garrett Lisi presents a controversial new model of the universe that -- just maybe -- answers all the big questions. If nothing else, it's the most beautiful 8-dimensional model of elementary particles and forces you've ever seen.

My radical plan for small nuclear fission reactors

Taylor Wilson was 14 when he built a nuclear fusion reactor in his parents' garage. Now 19, he returns to the TED stage to present a new take on an old topic: fission. Wilson, who has won backing to create a company to realize his vision, explains why he's so excited about his innovative design for small modular fission reactors -- and why it could be the next

Why we need the explorers

In tough economic times, our exploratory science programs -- from space probes to the LHC -- are first to suffer budget cuts. Brian Cox explains how curiosity-driven science pays for itself, powering innovation and a profound appreciation of our existence.

A robot that runs and swims like a salamander

Roboticist Auke Ijspeert designs biorobots, machines modeled after real animals that are capable of handling complex terrain and would appear at home in the pages of a sci-fi novel. The process of creating these robots leads to better automata that can be used for fieldwork, service, and search and rescue. But these robots don't just mimic the natural world — they

Murray Gell-Mann on beauty and truth in physics

Armed with a sense of humor and laypeople's terms, Nobel winner Murray Gell-Mann drops some knowledge on TEDsters about particle physics, asking questions like, Are elegant equations more likely to be right than inelegant ones?

Aliens, love -- where are they?

Humorist John Hodgman rambles through a new story about aliens, physics, time, space and the way all of these somehow contribute to a sweet, perfect memory of falling in love.

What went wrong at the LHC

In this short talk from TED U 2009, Brian Cox shares what's new with the CERN supercollider. He covers the repairs now underway and what the future holds for the largest science experiment ever attempted.

My friend Richard Feynman

What's it like to be pals with a genius? Onstage at TEDxCaltech, physicist Leonard Susskind spins a few stories about his friendship with the legendary Richard Feynman, discussing his unconventional approach to problems both serious and ... less so.

A new equation for intelligence

Is there an equation for intelligence? Yes. It’s F = T ∇ Sτ. In a fascinating and informative talk, physicist and computer scientist Alex Wissner-Gross explains what in the world that means. (Filmed at TEDxBeaconStreet.)

What we can learn from galaxies far, far away

In a fun, exciting talk, teenager Henry Lin looks at something unexpected in the sky: distant galaxy clusters. By studying the properties of the universe's largest pieces, says the Intel Science Fair award winner, we can learn quite a lot about scientific mysteries in our own world and galaxy.

The discovery that could rewrite physics

On March 17, 2014, a group of physicists announced a thrilling discovery: the “smoking gun” data for the idea of an inflationary universe, a clue to the Big Bang. For non-physicists, what does it mean? TED asked Allan Adams to briefly explain the results, in this improvised talk illustrated by Randall Munroe of xkcd.

Distant time and the hint of a multiverse

At TEDxCaltech, 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.

Michael Moschen juggles rhythm and motion

Michael Moschen puts on a quietly mesmerizing show of juggling. Don't think juggling is an art? You might just change your mind after watching Moschen in motion.

What physics taught me about marketing

Physics and marketing don't seem to have much in common, but Dan Cobley is passionate about both. He brings these unlikely bedfellows together using Newton's second law, Heisenberg's uncertainty principle, the scientific method and the second law of thermodynamics to explain the fundamental theories of branding.

Fusion is energy's future

Physicist Steven Cowley is certain that nuclear fusion is the only truly sustainable solution to the fuel crisis. He explains why fusion will work -- and details the projects that he and many others have devoted their lives to, working against the clock to create a new source of energy.

Symmetry, reality's riddle

The world turns on symmetry -- from the spin of subatomic particles to the dizzying beauty of an arabesque. But there's more to it than meets the eye. Here, Oxford mathematician Marcus du Sautoy offers a glimpse of the invisible numbers that marry all symmetrical objects.

Chemical scum that dream of distant quasars

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.

A new way to explain explanation

For tens of thousands of years our ancestors understood the world through myths, and the pace of change was glacial. The rise of scientific understanding transformed the world within a few centuries. Why? Physicist David Deutsch proposes a subtle answer.

Making sense of a visible quantum object

Physicists are used to the idea that subatomic particles behave according to the bizarre rules of quantum mechanics, completely different to human-scale objects. In a breakthrough experiment, Aaron O'Connell has blurred that distinction by creating an object that is visible to the unaided eye, but provably in two places at the same time. In this talk he suggests an

Sean Gourley on the mathematics of war

By analyzing raw data on violent incidents in the Iraq war and others, Sean Gourley and his team claim to have found a surprisingly strong mathematical relationship linking the fatality and frequency of attacks.

This new telescope might show us the beginning of the universe

When and how did the universe begin? A global group of astronomers wants to answer that question by peering as far back in time as a large new telescope will let us see. Wendy Freedman headed the creation of the Giant Magellan Telescope, under construction in South America; at TEDGlobal in Rio, she shares a bold vision of the discoveries about our universe that the

Let's look for life in the outer solar system

Physicist Freeman Dyson suggests that we start looking for life on the moons of Jupiter and out past Neptune, in the Kuiper belt and the Oort cloud. He talks about what such life would be like -- and how we might find it.

George Dyson on Project Orion

Author George Dyson spins the story of Project Orion, a massive, nuclear-powered spacecraft that could have taken us to Saturn in five years. His insider’s perspective and a secret cache of documents bring an Atomic Age dream to life.

Shedding light on dark matter

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.

Neil Turok makes his TED Prize wish

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.

Paul Rothemund details DNA folding

In 2007, Paul Rothemund gave TED a short summary of his specialty, DNA folding. Now he lays out in clear, abundant detail the immense promise of this field -- to create tiny machines that assemble themselves.

Charles Elachi on the Mars Rovers

At Serious Play 2008, Charles Elachi shares stories from NASA's legendary Jet Propulsion Lab -- including tales and video from the Mars Rover project.

The hunt for a supermassive black hole

With new data from the Keck telescopes, Andrea Ghez shows how state-of-the-art adaptive optics are helping astronomers understand our universe's most mysterious objects: black holes. She shares evidence that a supermassive black hole may be lurking at the center of the Milky Way.

Murray Gell-Mann on the ancestor of language

After speaking at TED2007 on elegance in physics, the amazing Murray Gell-Mann gives a quick overview of another passionate interest: finding the common ancestry of our modern languages.

How to air-condition outdoor spaces

During the hot summer months, watching an outdoor sports match or concert can be tantamount to baking uncomfortably in the sun -- but it doesn’t have to be. At the TEDxSummit in Doha, physicist Wolfgang Kessling reveals sustainable design innovations that cool us from above and below, and even collects solar energy for later use.

A history of the universe in sound

Artist-technologist Honor Harger listens to the weird and wonderful noises of stars and planets and pulsars. In her work, she tracks the radio waves emitted by ancient celestial objects and turns them into sound, including "the oldest song you will ever hear," the sound of cosmic rays left over from the Big Bang.

Lee Smolin on science and democracy

Physicist Lee Smolin talks about how the scientific community works: as he puts it, "we fight and argue as hard as we can," but everyone accepts that the next generation of scientists will decide who's right. And, he says, that's how democracy works, too.

Adam Sadowsky engineers a viral music video

The band "OK Go" dreamed up the idea of a massive Rube Goldberg machine for their next music video -- and Adam Sadowsky's team was charged with building it. He tells the story of the effort and engineering behind their labyrinthine creation that quickly became a YouTube sensation.

3 moons and a planet that could have alien life

Is there life beyond Earth? Join NASA's director of planetary science James Green for a survey of the places in our solar system that are most likely to harbor alien life.

What the discovery of gravitational waves means

More than a billion years ago, two black holes in a distant galaxy locked into a spiral, falling inexorably toward each other, and collided. "All that energy was pumped into the fabric of time and space itself," says theoretical physicist Allan Adams, "making the universe explode in roiling waves of gravity." About 25 years ago, a group of scientists built a giant

The untapped genius that could change science for the better

Jedidah Isler dreamt of becoming an astrophysicist since she was a young girl, but the odds were against her: At that time, only 18 black women in the United States had ever earned a PhD in a physics-related discipline. In this personal talk, she shares the story of how she became the first black woman to earn a PhD in astrophysics from Yale — and her deep belief in