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[Music]

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My name is Professor Michio Kaku.

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I'm a professor of theoretical physics at the City University of New York,

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and I specialize in something called String Theory.

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I'm a physicist, and some people ask me the question:

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"What has physics done for me lately? I mean, do I get better color television?

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Do I get better internet reception with physics?"

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And the answer is: yes.

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You see, physics is at the very foundation of matter and energy.

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We physicists invented the laser beam, we invented the transistor,

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we helped to create the first computer, we helped to construct the internet,

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we wrote the World Wide Web.

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In addition, we also helped to invent television, radio, radar, microwaves,

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not to mention MRI scans, PET scans, X rays.

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In other words, almost everything you see in your living room,

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almost everything you see in a modern hospital, at some point or other, can be traced to a physicist.

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Now, I got interested in physics when I was a child.

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When I was 8, a great scientist had just died.

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I still remember my elementary school teacher coming into the room and announcing that

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the greatest scientist of our era has just passed away.

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And that day, every newspaper published a picture of his desk,

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the desk of Albert Einstein.

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And the caption said -- I'll never forget--

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"The unfinished manuscript of the greatest work of the greatest scientist of our time."

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And I said to myself: "Why couldn't he finish it? I mean, what's so hard?

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It's a homework problem, right? Why didn't he ask his mother? Why can't he finish this problem?"

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So, as a child of eight, I decided to find out what was this problem?

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Years later, I began to realize that it was the theory of everything: the Unified Field Theory.

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An equation that would summarize all the physical forces in the universe.

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An equation like e = mc^2. That equation is half an inch long,

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and that equation unlocks a secret of the stars.

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Why do the stars shine? Why does the galaxy light up?

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Why do we have energy on the earth?

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But then there was another thing that happened to me when I was around eight years old.

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I got hooked on the Saturday morning TV shows. In particular, Flash Gordon.

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And I was hooked. I mean, every Saturday morning, watching programs about aliens from outer space:

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Starships, ray guns, invisibility shields, cities in the sky--that was for me.

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But after a few years, I began to notice something.

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First of all, I began to notice that, well, I didn't have blonde hair and blue eyes,

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I didn't have muscles like Flash Gordon, but it was a scientist who made the series work.

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In particular, a physicist.

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He was the one who discovered the ray gun, the starships.

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He was the one who created the invisibility shield.

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And then I realized something else: If you want to understand the future,

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you have to understand physics.

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Physics is at the foundation of all, the gadgetry, the wizardry,

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all the marvels of the technological age, all of it can be traced

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to the work of a physicist.

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Most of science fiction is, in fact, well within the laws of physics,

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but possible within maybe a hundred years.

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Then we have impossibilities that may take a thousand years or more.

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That includes time travel, warp drive, higher dimensions,

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portals through space and time, stargates, wormholes.

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You know--if you were to meet your great grandparents of the year 1900,

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they were dirt farmers back then.

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They didn't live much beyond the age of 40, on average.

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Long distance communication in the year 1900 was yelling at your neighbor,

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and yet, if they could see you now,

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with iPads and iPods and satellites and GPS and laser beams,

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how would they view you?

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They may view you as a wizard or sorcerer.

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However, if we can now meet our grand kids of the year 2100,

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how would we view them?

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We would view them as gods like in Greek mythology.

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Zeus could control objects around him by pure thought,

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materialize objects just by thinking,

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and there are perks to being a Greek god.

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Venus had a perfect body, a timeless body,

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and we are beginning now to unravel the genetics at the molecular level of the aging process.

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And then Apollo, he had a chariot that he could ride across the heavens.

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We will finally have that flying car that we have always wanted to have in our garage by the year 2100.

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We will have the power of the gods.

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To paraphrase Arthur C. Clarke,

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"Any sufficiently advanced technology is indistinguishable from divinity."

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[Music]

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So, let's now begin our story.

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The history of physics is the history of modern civilization.

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Before Isaac Newton, before Galileo

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we were shrouded with the mysteries of superstition.

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People believed in all sorts of different kinds of spirits and demons.

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What made the planets move?

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Why do things interact with other things? It was a mystery.

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So, back in the middle ages, for example,

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people read the works of Aristotle, and Aristotle asked a question

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"Why do objects move toward the earth?"

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And that's because, he said, "Objects yearn--yearn to be united with the earth."

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And why do objects slow down when you put them in motion?

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"Objects in motion slow down because they get tired."

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These are the works of Aristotle, which held sway for almost 2,000 years until the beginning of modern with Galileo and Isaac Newton.

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[Music]

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When the ancients looked at the sky, the sky was full of mystery and wonder.

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And in the year 1066, the most important date on the British calendar,

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there was a comet--a comet would sail over the battlefield of Hastings.

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It frightened the troops of King Harold, and a young man from Normandy

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swept into England and defeated King Harold at the Battle of Hastings,

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creating the modern British monarchy.

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But the question is, where did the comet come from?

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What was this comet that mysteriously paved the way for the coming of the British monarchy?

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Well, believe it or not, that same comet--the very same comet

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that initiated the British monarchy

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sailed over London once again in 1682.

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This time, everyone was asking the question, where do comets come from?

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Do they signal the death of the king?

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Why do we have messengers from the heavens in the sky?

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Well, one man dared to penetrate the secrets of comets,

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and that was Isaac Newton.

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In fact, when Isaac Newton was only 23 years old, he stumbled upon the universal force of gravitation.

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According to one story, he was walking on his estate in Wilsthorpe and he saw an apple fall.

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And then Isaac Newton saw the moon.

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And then he asked the key question which helped to unlock the heavens:

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"If apples fall, does the moon also fall?"

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And the answer was: Yes.

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And that answer overturned thousands of years of mystery and speculation about the motions of the heavens.

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The moon is in free fall just like an apple.

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The moon is constantly falling toward the earth.

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It doesn't hit the Earth because it spins around the Earth, and the Earth is round,

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but it's acting under a force--a force of gravity.

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So, Newton immediately tried to work out the mathematics.

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And he realized that the mathematics of this 1600's was not sufficient to work out the motion

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of a falling moon.

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So, what did Isaac Newton do?

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When he was 23 years old, not only did he stumble upon the force of gravity,

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but he also created Calculus.

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In fact, he created Calculus at the rate at which you learn it when you are a freshman in college.

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And why did he create Calculus?

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To calculate the motion of a falling moon.

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The mathematics of this age was incapable of calculating

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the trajectories of objects moving under an inverse square force field.

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And that's what Isaac Newton did; he worked out the motion of the moon,

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and then he realized that if he understands the moon,

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he also understands the motion of the planets in the solar system.

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And Isaac Newton invented a new telescope.

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It was the reflecting telescope, and he was tracking the motion of this comet.

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Well, it turns out that everyone was talking about the comet, including a rather wealthy Englishman by the name of Edmund Halley.

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So, Edmund Halley, being a wealthy merchant, decided to make a trip to Cambridge

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to talk to England's illustrious scientist, Sir Isaac Newton.

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Well, Edmund Halley asked Newton, "What do you make of this comet?"

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"No one understands comets, they're a mystery."

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"They've been fascinating people for centuries, for millennia--what are your thoughts?"

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And then, I paraphrase, but Isaac Newton said something like this.

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He said, "Oh, that's easy. That comet is moving at a perfect ellipse. It's moving in an inverse square force field."

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"I've been tracking it every day with my reflecting telescope, and the path of that comet

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conforms to my mathematics exactly."

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And, of course, we don't know what Edmund Halley's reaction was, but I paraphrase.

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He must have said something like this, "For God's sake, man, why don't you publish the greatest work

0:11:16.191,0:11:19.351
in all of scientific history?

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If correct, you have decoded the secret of the stars, the secret of the heavens.

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Nobody understands where comets come from!"

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And then Newton responded and said, "Oh, well, it costs too much. I mean, I'm not a wealthy man."

0:11:35.879,0:11:42.268
"It would cost too much to summarize this calculus that I've invented and to work out all the motion of the stars."

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And then Halley must have said this, "Mister Newton, I am a wealthy man."

0:11:47.864,0:11:58.218
"I have made my fortune in congress. I will pay for the publication of the greatest scientific work in any language."

0:11:58.218,0:12:05.482
And it was "Principia" the principles--the mathematical principles that guide the heavens.

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Believe it or not, this is perhaps one of the most important works

0:12:10.738,0:12:18.519
ever written by a human being in the hundred thousand years since we evolved from Africa.

0:12:18.519,0:12:24.826
Realize that this book sets into motion a physics of the universe.

0:12:24.826,0:12:32.743
Forces that control the motion of the planets, forces which can be calculated, forces which govern

0:12:32.743,0:12:41.813
the motion of cannonballs, rockets, pebbles--everything that moves moves according to the Laws of Motion

0:12:41.813,0:12:45.317
and the Calculus of Sir Isaac Newton.

0:12:45.317,0:12:50.823
In fact, even today when we launch our space probes, we don't use Einstein's equations,

0:12:50.823,0:12:54.910
they only apply when you get near the speed of light or near a black hole.

0:12:54.910,0:12:57.331
We use Newton's Laws of Gravity.

0:12:57.331,0:13:02.455
They are so precise that when we shoot a space probe right past the rings of Saturn,

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we use exactly the same equations that Isaac Newton unraveled in the 1600's.

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That's why we've been able to unravel the secrets of the solar system--

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complements of the Laws of Motion of Isaac Newton.

0:13:17.665,0:13:24.501
So, what Newton did was not only did he set into motion the ability to calculate planets,

0:13:24.501,0:13:27.973
he also set into motion a mechanics.

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Machines now operated upon well-defined laws.

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Newton's three laws of motion: the first law of motion says that objects in motion stay in motion forever

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unless acted upon by an outside force.

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You see that in an ice skating rink.

0:13:47.095,0:13:53.649
You shoot a puck and it goes all the way down forever, unless acted on by an outside force.

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That's different from Aristotle's Law of Motion.

0:13:56.840,0:14:03.315
Aristotle said, "Objects in motion eventually stop because they get tired."

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The second law of motion says, "Force is mass times acceleration."

0:14:08.064,0:14:13.553
And that equation made possible the Industrial Revolution.

0:14:13.553,0:14:20.272
Steam engines, locomotives, factories, machines, all of it due to the mechanics

0:14:20.272,0:14:27.225
set into motion by Isaac Newton's second law of motion, "Force is equal to mass times acceleration."

0:14:27.225,0:14:32.890
And then Newton had a third law of motion, "For every action there is an equal and opposite reaction."

0:14:32.890,0:14:35.351
That's the law of rockets.

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That's why we have rockets that can sail into outer space.

0:14:38.078,0:14:45.668
So, the lesson here is when scientists unraveled the first force of the universe, gravity,

0:14:45.668,0:14:53.866
that set into motion the industrial revolution--a revolution which toppled the kings and queens of Europe,

0:14:53.866,0:14:58.452
which displaced Feudalism, ushering in the Modern Age.

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All because a 23 year old gentleman looked up and asked the question, "Does the moon also fall?"

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You know--when I was a kid growing up in California, I would see pictures of the Empire State Building,

0:15:13.531,0:15:20.520
and I said to myself, "How could they possibly build such a big building and not know that it's going to fall?"

0:15:20.520,0:15:24.739
Why doesn't it fall? They didn't build scale models of the thing.

0:15:24.739,0:15:28.741
You couldn't have an Empire State Building that big to test whether it's going to fall or not.

0:15:28.741,0:15:33.956
How did they know ahead of time that that building wouldn't fall?

0:15:33.956,0:15:37.376
And the answer is: Newton's Laws of Motion.

0:15:37.376,0:15:41.624
In fact, today I teach Newton's Laws of Motion and you can actually calculate

0:15:41.624,0:15:46.889
the forces on every single brick of the Empire State Building.

0:15:46.889,0:15:52.301
Using Newton's second law of motion, "Force is mass times acceleration."

0:15:52.301,0:15:57.252
When Newton unraveled the force of gravity, that was the first force.

0:15:57.745,0:16:00.185
Now let's take a look at the second force--

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an even greater force, which has touched all of our lives.

0:16:03.653,0:16:07.245
And that is the electromagnetic force.

0:16:08.122,0:16:15.927
Ever since humans saw lightning bolts light up the sky, ever since they were terrified by the sound of thunder,

0:16:15.927,0:16:23.834
they've been asking, "Do the gods propel lightning bolts and create thunder? Are they angry at us?" [Crashing thunder]

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Scientists began to realize that the lightning bolts and the thunder can be duplicated on the earth,

0:16:31.428,0:16:35.892
that we can actually create mini-lightning bolts using electricity. [Buzzing]

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But it wasn't until the 1800's that finally we began to unlock the second great force which rules the universe--

0:16:44.736,0:16:46.887
the electromagnetic force.

0:16:46.887,0:16:53.207
Michael Faraday would give Christmas lectures in London, fascinating everyone from adults to children

0:16:53.207,0:16:58.577
and he would demonstrate the incredible properties of electricity.

0:16:58.577,0:17:04.323
Some people, for example, ask a simple question, "If you're in a car or an airplane and you get hit by a lightning bolt,

0:17:04.323,0:17:07.550
why don't you all get electrocuted, why don't you all die?"

0:17:07.550,0:17:09.856
Well, Faraday answered the question.

0:17:09.856,0:17:12.261
He would create a cage.

0:17:12.261,0:17:18.689
He would walk into this steel cage, electrify it, and he wouldn't get electrocuted at all.

0:17:18.689,0:17:26.975
That's called a Faraday Cage, and every time you walk into a metal structure, you get shielded by this metal object.

0:17:26.975,0:17:32.450
Well, what Michael Faraday did was he helped to unleash the second great revolution

0:17:32.450,0:17:36.128
with something called Faraday's Law.

0:17:36.713,0:17:44.796
A moving wire in a magnetic field has its electrons pushed, creating an electrical current.

0:17:45.641,0:17:54.885
That simple idea, unleashed the electric revolution, and that's why we have hydro-electric generators,

0:17:54.885,0:18:00.031
dams that can produce enormous amounts of power, that's why people build nuclear power plants,

0:18:00.031,0:18:04.143
that's why we have electricity in this room right now.

0:18:04.143,0:18:07.016
On a very small scale, you use that in your bicycle.

0:18:07.016,0:18:12.291
When you put a bicycle amp on your bicycle, the turning of the wheel spins a magnet.

0:18:12.291,0:18:19.660
The magnet then pushes electrons in a wire, and that's why electricity lights up in your bicycle lamp.

0:18:19.660,0:18:25.696
So, in other words, electricity and magnetism were unified into a single force.

0:18:26.128,0:18:29.063
We once thought that electricity and magnetism were separate.

0:18:29.063,0:18:33.828
Now we know that they are, in fact, the same force.

0:18:34.813,0:18:39.916
So, if a moving magnet can create an electric field,

0:18:39.916,0:18:45.088
this means that the moving electric field can create a magnetic field.

0:18:45.088,0:18:52.585
But if they can create each other, why can't they oscillate and create a wave

0:18:52.585,0:18:59.341
so that moving electric fields create magnetic fields create electric fields create magnetic fields infinitum

0:18:59.341,0:19:00.954
to create a wave?

0:19:00.954,0:19:06.458
Well, around the time of the American Civil War, a mathematical physicist, James Clerk Maxwell,

0:19:06.458,0:19:11.897
calculated using the work of Faraday the velocity of this wave.

0:19:11.897,0:19:18.900
In one of the greatest breakthroughs of all time, James Clerk Maxwell calculated the velocity of this wave

0:19:18.900,0:19:23.695
and found that it was the velocity of light.

0:19:24.019,0:19:28.350
And then he made this incredible discovery.

0:19:28.350,0:19:31.870
This is light.

0:19:32.594,0:19:35.896
That's what light is.

0:19:35.896,0:19:41.856
It doesn't by accident travel at the speed of electricity, it is light itself.

0:19:41.856,0:19:45.447
And the equations were written down by James Clerk Maxwell.

0:19:45.447,0:19:49.274
Unfortunately, Michael Faraday himself did not have a formal education.

0:19:49.274,0:19:52.876
He could not put into mathematical form his own work.

0:19:52.876,0:19:56.963
James Clerk Maxwell was a theoretical physicist, just like myself.

0:19:56.963,0:20:02.685
He wrote down the mathematical physics of oscillating electric fields and magnetic fields,

0:20:02.685,0:20:06.174
and they are called Maxwell's Equations.

0:20:06.174,0:20:11.172
These equations have to be memorized by every physicist in grad school.

0:20:11.172,0:20:15.660
You can not get your PhD without memorizing these equations.

0:20:15.660,0:20:19.957
Every engineer who deals with radar and radio has to memorize these equations.

0:20:19.957,0:20:24.992
And so, if you go to Berkeley, where I got my PhD, you can buy a t-shirt which says,

0:20:24.992,0:20:35.642
"In the beginning God said the four dimensional divergence of an anti-symmetric, second rank tensor = 0, and there was light."

0:20:35.642,0:20:41.719
Ladies and gentleman, this is the equation for light. [Music]

0:20:43.827,0:20:48.516
The consequences of the electromagnetic revolution touched all of us.

0:20:48.516,0:20:50.812
This is a picture of the Earth from outer space.

0:20:50.812,0:20:52.024
Look at this picture!

0:20:52.024,0:20:59.563
Europe electrified! You can actually see the fruits of all of our efforts to create electricity

0:20:59.563,0:21:05.720
to energize our lives in one picture--seeing the Earth from outer space.

0:21:05.720,0:21:11.926
So, let's now talk about how Faraday and Maxwell's work touches your life as well.

0:21:11.926,0:21:17.164
This is the internet. The internet is a simple byproduct of the electromagnetic force,

0:21:17.164,0:21:20.975
and you can see that where there is the internet, there is prosperity,

0:21:20.975,0:21:25.490
there's science, there's entertainment, there's economic activity.

0:21:25.490,0:21:29.428
Where there's no internet, there's poverty.

0:21:29.428,0:21:34.961
And in the future, the internet will be miniaturized and will be placed in your glasses.

0:21:34.961,0:21:41.780
Your glasses will recognize people's faces and display their biography next to the image as you talk to them,

0:21:41.780,0:21:47.378
and then when they speak Chinese to you, your glasses will translate Chinese into English

0:21:47.378,0:21:51.569
and print out subtitles right beneath their image.

0:21:51.569,0:21:57.225
So, in the future, you will know exactly who you are talking to without even talking to them,

0:21:57.225,0:22:03.658
and this means that at a cocktail party, if you're looking for a job, but you don't know who the heavy hitters are,

0:22:03.658,0:22:07.987
in the future, you will know exactly who to suck up to.

0:22:07.987,0:22:14.906
In the future, chips will only cost a penny, because we can manufacture tinier and tinier transistors.

0:22:14.906,0:22:19.227
You will have Faraday's electromagnetic force inside your body.

0:22:19.227,0:22:22.450
This is a pill. It has a chip in it.

0:22:22.450,0:22:24.912
The chip is smaller than an aspirin pill.

0:22:24.912,0:22:27.867
It also has a TV camera and a magnet.

0:22:27.867,0:22:34.725
When you swallow it, the magnet guides the camera, taking pictures of your stomach, your intestines--

0:22:34.725,0:22:38.937
because we all know what middle-aged men fear the most--colonoscopies.

0:22:38.937,0:22:44.877
And this gives new meaning to the expression "Intel Inside." [Eerie music]

0:22:46.139,0:22:51.253
Now, let's talk about the next great forces which rule the universe.

0:22:51.253,0:22:55.355
We talked about gravity, which allows us to calculate the motion of the planets.

0:22:55.679,0:23:00.863
The mechanics created by Newton helped to unleash the Industrial Revolution.

0:23:00.863,0:23:07.150
Michael Faraday worked out the electromagnetic force, which gave us the wonders of the Electric Age.

0:23:07.150,0:23:13.156
Now, let's talk about the Nuclear Age, the stars, and the sun. [Music]

0:23:13.972,0:23:16.938
People have been fascinated by the sun.

0:23:16.938,0:23:22.315
Apollo was a god that strode across the heavens in his fiery chariot--but hey--

0:23:22.315,0:23:28.060
when you calculate how long coal or oil will burn like the sun,

0:23:28.060,0:23:32.618
you'll realize that just in a few hundred years, the sun would burn to a crisp.

0:23:32.618,0:23:36.329
What could possibly last for billions of years?

0:23:36.329,0:23:38.969
There must be a new force--

0:23:38.969,0:23:40.867
a nuclear force.

0:23:41.882,0:23:47.379
Einstein and others helped to unravel the secret of the stars.

0:23:47.379,0:23:51.437
The nuclear force comes in two types: weak and strong.

0:23:51.437,0:23:55.364
The weak nuclear force governs radioactive decay.

0:23:55.364,0:24:00.448
The strong nuclear force is one of the strongest forces in the entire universe.

0:24:00.448,0:24:07.024
It's so strong it holds our protons together ever since genesis, the beginning of time.

0:24:07.024,0:24:13.450
The equation which allows for the liberation of energy is Einstein's famous equation:

0:24:13.450,0:24:16.461
E=mc^2

0:24:16.461,0:24:21.874
What Einstein showed was that the faster you move the heavier you get.

0:24:21.874,0:24:24.756
So, your weight is not a constant.

0:24:24.756,0:24:29.884
When you move very rapidly you get heavier--something which we measure every day in the laboratory.

0:24:29.884,0:24:39.162
Now, this means that the energy of motion transformed into mass--cause you get heavier.

0:24:39.162,0:24:45.345
Now, listen carefully. The faster you move, the heavier you get,

0:24:45.345,0:24:53.141
which means the energy of motion E turns into M, your mass, and the relationship

0:24:53.141,0:24:57.415
between E and M is very simple--it takes one second to write it down on a sheet of paper--

0:24:57.415,0:25:02.701
it is exactly e=mc^2.

0:25:02.701,0:25:09.455
So, the nuclear force helped to explain the secret of the sun, but it also created a Pandora's box,

0:25:09.455,0:25:15.386
because inside the nucleus of the atom are particles,

0:25:15.386,0:25:17.948
and when you smash these particles, what do you get?

0:25:17.948,0:25:20.934
More particles. And when you smash them, what do you get?

0:25:20.934,0:25:29.762
More particles. In fact, we are drowning in subatomic particles--hundreds, thousands of subatomic particles

0:25:29.762,0:25:31.870
every time we smash atoms.

0:25:31.870,0:25:37.277
Now, we smash atoms using something called atom smashers, or particle accelerators.

0:25:37.277,0:25:41.109
I built my own particle accelorater when I was in high school.

0:25:41.109,0:25:46.426
When I was in high school, I went to my mom one day, and I said, "Mom, can I have permission to build

0:25:46.426,0:25:51.578
a 2.3 million electron volt betatron particle accelerator in the garage?"

0:25:51.578,0:25:57.993
And my mom said, "Sure, why not? And don't forget to take out the garbage."

0:25:57.993,0:26:03.795
So, I went to Westinghouse, and as high school kid, I asked for 400 pounds of transformer steel.

0:26:03.795,0:26:07.562
I asked for 22 miles of copper wire--cause I wanted to create

0:26:07.562,0:26:11.870
a 6 kilowatt, 10,000 gauss magnetic field to energize my atom smasher.

0:26:11.870,0:26:15.076
With 22 miles of copper wire, how can you wind it?

0:26:15.076,0:26:17.359
We did it on the high school football field.

0:26:17.359,0:26:23.977
I put 22 miles of copper wire on the goal post, gave it to my mother, she ran to the 50 yard line,

0:26:23.977,0:26:26.577
unraveling the spool of wire.

0:26:26.577,0:26:29.339
She gave it to my father, who then ran to the goal post,

0:26:29.339,0:26:33.824
and we wound 22 miles of copper wire on the high school football field.

0:26:33.824,0:26:37.103
Well, finally my atom smasher was ready.

0:26:37.103,0:26:42.678
It consumed 6 kilowatts of power--that's every single ounce of power that my house could deliver.

0:26:42.678,0:26:52.379
I plugged my ears, I closed my eyes, I turned on the power, and I heard this huge crackling sound

0:26:52.379,0:26:56.451
as 6 kilowatts of power surged through my capacitor bank.

0:26:56.451,0:27:02.264
And then I heard a pop-pop-pop sound as I blew out every single circuit breaker in the house.

0:27:03.510,0:27:06.589
The whole house was plunged in darkness.

0:27:06.589,0:27:12.698
My poor mom--every time she'd come home, she would see the lights flicker and die.

0:27:12.698,0:27:20.223
And she must have wondered, "Why couldn't I have a son who plays baseball. Why can't he learn basketball?

0:27:20.223,0:27:22.934
And, for God's sake, why can't he find a nice Japanese girl?"

0:27:22.934,0:27:27.873
"I mean--why does he have to build these machines in the garage?"

0:27:27.873,0:27:36.893
Well, these machines I built in my garage are in the attention of a physicist, Edward Teller, father of the hydrogen bomb.

0:27:36.893,0:27:42.303
And he arranged for me to get a scholarship to Harvard, and my career got a head start.

0:27:42.303,0:27:45.253
He knew exactly what I was doing.

0:27:45.253,0:27:48.748
I didn't have to explain to him that I was experimenting with antimatter.

0:27:48.748,0:27:55.517
I was creating anti-electrons in my mom's garage and using atom smashers to, eventually, create beams of antimatter.

0:27:55.517,0:28:01.490
Antimatter is the opposite of matter. It has the opposite charge.

0:28:01.490,0:28:03.926
So, an electron has negative charge.

0:28:03.926,0:28:07.314
The positron, or anti-electron, has positive charge.

0:28:07.314,0:28:11.877
This means that you can now create anti-molecules and anti-atoms.

0:28:11.877,0:28:18.404
Anti-hydrogen was made at CERN outside Geneva, Switzerland and also at Fermilab outside Chicago,

0:28:18.404,0:28:23.649
where they have anti-electrons circulating around anti-protons.

0:28:23.649,0:28:28.961
And in Brookhaven National Laboratory in Long Island just recently, they detected anti-helium.

0:28:28.961,0:28:35.789
We have two anti-protons with two anti-neutrons to create anti-helium.

0:28:35.789,0:28:40.961
For every piece of matter, there's a counterpart which is made out of antimatter.

0:28:40.961,0:28:46.896
And, when the two collide, by the way, it releases the greatest energy source in the universe. [Beaming sounds]

0:28:47.866,0:28:54.594
It is 100% conversion of matter to energy by Einstein's equations: e=mc^2. [Phasing sounds]

0:28:58.102,0:29:04.486
Inside the nucleus of the atom, we have particles upon particles when you smash them apart.

0:29:04.486,0:29:09.027
In the 1950's, we were drowning in subatomic particles.

0:29:09.027,0:29:15.190
In fact, J. Robert Oppenheimer, the father of the atomic bomb once made a statement.

0:29:15.190,0:29:25.183
He declared that "The Nobel Prize in physics should go to the physicist who does not discover a new particle this year."

0:29:25.183,0:29:27.810
That's how many particles were being discovered. [Music]

0:29:27.810,0:29:31.564
So, let's talk about the particle zoo.

0:29:31.564,0:29:38.912
Right now, we physicists have unlocked hundreds, thousands of subatomic particles,

0:29:38.912,0:29:42.386
and we've been able to piece them together into a jigsaw puzzle.

0:29:42.386,0:29:44.402
It's called the Standard Model.

0:29:44.402,0:29:52.857
It has 36 quarks, 19 free parameters, 3 generations of quarks, no rhyme, no reason,

0:29:52.857,0:30:01.072
but this is the most fundamental basis of reality that we physicists have been able to construct.

0:30:01.072,0:30:08.038
Billions of dollars, 20 Nobel Prizes have gone into the creation of the Standard Model,

0:30:08.038,0:30:13.585
and it is the ugliest theory known to science, but it works.

0:30:13.585,0:30:18.491
There is one piece missing, and the one piece that is missing is called the higgs boson.

0:30:18.491,0:30:23.890
We expect to find it. We want to create a higher version of this theory.

0:30:23.890,0:30:28.393
And that theory, we think, is String Theory.

0:30:29.332,0:30:35.274
String theory is based on the simple idea that all the four forces of the universe--

0:30:35.274,0:30:43.290
Gravity, the electromagnetic force, and the two nuclear forces--can be viewed as music. [Music]

0:30:44.060,0:30:47.024
Music of tiny little rubber bands.

0:30:47.024,0:30:53.004
So, if I had a super microscope and I could look right into the heart of an electron, what would I see?

0:30:53.004,0:30:57.503
I would see a vibrating rubber band, and if I twang it, it turns into a neutrino.

0:30:57.503,0:30:59.510
If I twang it again, it turns into a quark.

0:30:59.510,0:31:02.357
I twang it again, it turns into a Yang-Mills particle.

0:31:02.357,0:31:07.566
In fact, if I twang it enough times, I get thousands of subatomic particles

0:31:07.566,0:31:11.924
that have been cataloged patiently by physicists.

0:31:13.923,0:31:18.107
String theory, we think, is a theory of everything.

0:31:18.107,0:31:25.491
Now, string theory, in turn, can be summarized in an equation about an inch long--that's my equation.

0:31:25.491,0:31:29.664
This is called String Field Theory, and how will we test it?

0:31:29.664,0:31:38.420
We are building a machine--the biggest machine of science ever built in the history of the human race--

0:31:38.420,0:31:41.111
outside Geneva, Switzerland.

0:31:41.111,0:31:45.589
It is the Large Hadron Collider.

0:31:45.589,0:31:50.350
So, the higgs boson,we think, will be created by the Large Hadron Collider.

0:31:50.350,0:31:55.956
A tube with 17 miles in circumference with two beams of protons circulating in opposite directions

0:31:55.956,0:32:02.914
then slamming together, creating a shower of particles, and among these particles

0:32:02.914,0:32:05.659
we hope to find the higgs boson, but not only that.

0:32:05.659,0:32:09.286
We hope to find particles even beyond the higgs boson.

0:32:09.286,0:32:13.285
The next set of particles beyond the higgs boson are sparticles.

0:32:13.285,0:32:17.661
The next layer of the jigsaw puzzle are called sparticles, super particles--

0:32:17.661,0:32:23.176
nothing but higher vibrations, higher musical notes of a vibrating string.

0:32:23.176,0:32:25.077
And what else could we do?

0:32:25.077,0:32:28.140
We can also unlock the secrets of the Big Bang.

0:32:28.140,0:32:35.489
You see, Einstein's equations break down at the instant of the big bang and the center of a black hole.

0:32:35.489,0:32:44.347
The two most interesting places in the universe are beyond our reach using Einstein's equations.

0:32:44.347,0:32:47.692
We need a higher theory, and that's where string theory comes in.

0:32:47.692,0:32:53.675
String theory takes you before the big bang, before genesis itself.

0:32:53.675,0:32:55.935
And what does string theory say?

0:32:55.935,0:33:00.931
It says that there is a multiverse of universes.

0:33:02.146,0:33:04.512
Where did the big bang come from?

0:33:04.512,0:33:12.652
Well, Einstein's equations give us this compelling picture that we are like insects on a soap bubble--

0:33:12.652,0:33:20.277
a gigantic soap bubble just expanding, and we are trapped like flies on fly paper, we can't escape the soap bubble.

0:33:20.277,0:33:22.518
That's called the Big Bang Theory.

0:33:23.442,0:33:28.375
String theory says there should be other bubbles out there.

0:33:28.375,0:33:32.609
In a multiverse of bubbles when two universes collide,

0:33:32.609,0:33:36.176
it can form another universe.

0:33:36.176,0:33:43.770
When a universe splits in half, it can create two universes, and that, we think, is the big bang.

0:33:43.770,0:33:51.559
The big bang is caused either by the collision of universes or by the fissioning of universes.

0:33:53.559,0:34:00.315
If there are other dimensions, if there are other universes, can we go between universes?

0:34:00.315,0:34:02.493
Well, that, of course, is very hard.

0:34:02.493,0:34:07.843
However, Alice in Wonderland gives us a possibility that,

0:34:07.843,0:34:12.580
maybe one day, we might create a worm hole between universes.

0:34:13.841,0:34:16.379
This is a wormhole.

0:34:16.379,0:34:21.033
Think of taking a sheet of paper and putting two dots on it.

0:34:21.033,0:34:24.971
The shortest distance between two points is a straight line,

0:34:24.971,0:34:32.649
but if I can fold--if I can fold that sheet of paper, then perhaps I can create a shortcut,

0:34:32.649,0:34:36.942
a shortcut through space and time called the wormhole.

0:34:36.942,0:34:40.100
This is a genuine solution of Einstein's equations.

0:34:40.100,0:34:42.527
We can actually see this in string theory.

0:34:42.527,0:34:47.578
The question is how practical is it to go through one of these things?

0:34:47.578,0:34:51.451
We don't know. In fact there's a debate among physicists today--

0:34:51.451,0:34:54.497
Steven Hawking, many physicists are jumping into the game,

0:34:54.497,0:35:01.751
trying to figure out whether it's physically possible to go all the way through a wormhole.

0:35:04.087,0:35:09.030
Because if you could, then you might be able to use this as a time machine.

0:35:09.030,0:35:14.014
Since string theory is the theory of everything, it's also a theory of time,

0:35:14.014,0:35:17.506
and time machines are allowed in Einstein's equations,

0:35:17.506,0:35:22.415
but to build one is extremely difficult.

0:35:22.415,0:35:27.745
Far more energy is required than a simple Delorean with plutonium.

0:35:31.803,0:35:36.171
You know--trillions of years from now, the universe is going to get awfully cold.

0:35:36.171,0:35:38.942
We think the universe is headed for a big freeze.

0:35:38.942,0:35:43.190
All the stars will blink out. Stars will cease to twinkle.

0:35:43.190,0:35:47.294
The universe will be so big, it'll be very cold.

0:35:47.294,0:35:53.125
At that point, all intelligent life in the universe must die.

0:35:53.125,0:35:59.171
The laws of physics are a death warrant to all intelligent life.

0:35:59.171,0:36:02.829
There's only one way to escape the death of the universe,

0:36:02.829,0:36:06.695
and that is: leave the universe.

0:36:06.695,0:36:11.902
Well, you're now, of course, entering the realm of science fiction, but at least we now have equations--

0:36:11.902,0:36:18.871
the equations of string theory, which will allow us to calculate if it is possible to go through a wormhole

0:36:18.871,0:36:24.554
to go to another universe where it's warmer, and perhaps we can start all over again.

0:36:28.311,0:36:33.916
If you were to summarize the march of physics over the last ten thousand years,

0:36:33.916,0:36:40.424
it would be the distillation of the laws of nature into four fundamental forces:

0:36:40.424,0:36:44.533
Gravity, electricity and magnetism, and the two nuclear forces.

0:36:44.933,0:36:47.646
But then the question is, is there a fifth force--

0:36:47.646,0:36:51.803
a force beyond the forces that we can measure in the laboratory?

0:36:51.803,0:36:57.104
And, believe it or not, there are physicists who have actually looked very carefully for a fifth force.

0:36:57.104,0:37:00.068
Some people think maybe it's a psychic phenomena.

0:37:00.068,0:37:06.792
Maybe it's telepathy, maybe it's something called psy-power, maybe it's the power of the mind, maybe consciousness.

0:37:07.453,0:37:13.443
Well, I'm a physicist. We believe in testing theories to make sure that they are:

0:37:13.443,0:37:16.492
Falsifiable and reproducible.

0:37:16.815,0:37:22.620
We want to make sure that on demand, your theory works every single time without exception.

0:37:22.620,0:37:26.695
and if your theory fails one time, it's wrong.

0:37:26.695,0:37:32.335
In other words, Einstein's theory has to work every single time without exception.

0:37:32.335,0:37:37.448
One time, Einstein's theory is proven to be wrong, the whole theory is wrong.

0:37:37.448,0:37:41.215
Well, so far we can reproduce these four physical theories,

0:37:41.215,0:37:45.845
but a fifth theory can not be reproduced--we've looked for it.

0:37:45.845,0:37:51.316
Some people think that maybe a fifth force may be short range, like not over the nucleus over the atom,

0:37:51.316,0:37:53.609
but ranging over several feet.

0:37:53.609,0:37:55.652
And we can't find any.

0:37:58.068,0:38:02.966
We physicists in the last ten years have discovered a new energy source

0:38:02.966,0:38:08.033
larger than the galaxy itself--dark energy.

0:38:08.033,0:38:14.192
Realize in our universe today, 73% of our universe--the matter and energy--

0:38:14.192,0:38:18.979
73% is in the form of dark energy--the energy of nothing.

0:38:18.979,0:38:22.300
That's what's blowing galaxies farther and farther apart.

0:38:22.300,0:38:25.943
That's the energy of the big bang itself.

0:38:25.943,0:38:30.342
Kids ask the question, "If the universe banged, then what made it bang?"

0:38:30.342,0:38:32.209
And the answer is: Dark energy.

0:38:32.209,0:38:35.943
73% of the universe's energy is dark energy.

0:38:35.943,0:38:40.028
23% is dark matter. Dark matter is invisible matter.

0:38:40.028,0:38:42.728
If I held it in my hand, it would go right through my hand.

0:38:42.728,0:38:47.924
It holds the galaxy together--23% of the universe is dark matter.

0:38:47.924,0:38:52.228
Stars, made out of hydrogen and helium, make up 4% of the universe.

0:38:52.228,0:39:00.923
And then what about us? We, the higher elements--we, made out of oxygen, carbon, nitrogen, tungsten, iron.

0:39:00.923,0:39:06.945
We make up 0.03% of the universe.

0:39:06.945,0:39:09.945
In other words, we are the exception.

0:39:09.945,0:39:16.013
The universe is mainly made out of dark energy. The universe is mainly made out of dark matter--

0:39:16.013,0:39:20.224
overwhelming the stars, overwhelming the galaxies, in fact.

0:39:20.224,0:39:25.429
Now, what is dark matter, which makes up 23% of the universe.

0:39:25.429,0:39:31.070
No one knows. String theory gives us a clue, but there is no definitive answer.

0:39:33.594,0:39:38.789
So, in other words, for you young, aspiring physicists in the audience,

0:39:38.789,0:39:42.653
you might be saying to yourself now, "Why should I go into physics,

0:39:42.653,0:39:46.222
because you guys already have a candidate for the unified field theory, right?"

0:39:46.222,0:39:52.465
Just realize that every single physics textbook is wrong.

0:39:52.465,0:39:57.355
Every single physics textbook on the Earth says that the universe is mainly made out of atoms, right?

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There it is, the universe is mainly made out of atoms.

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Wrong!

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In the last ten years, we have come to the realization that most of the universe is dark.

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And there's a whole shelf full of Nobel Prizes for the young people

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who can figure out the secret of dark matter and dark energy.

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Let me give some advice to you if you are a young physicist, perhaps just getting out of high school.

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You have dreams of being Einstein, dreams of working on string theory, and stuff like that.

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And then you hit freshman physics.

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Let me be blunt.

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We physicists flunk most students taking elementary physics,

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and we are more or less encouraged to do so by the engineering department.

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We don't want to train engineers who make bridges that fall down.

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We don't want to create engineers that create sky scrapers that fall over.

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There's a bottom line--you have to know the laws of mechanics.

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So, before you can work with the laws of Einstein, you have to work with the laws of friction, leavers, pullies, and gears.

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As a consequence, we have a very high flunk-out rate in elementary physics.

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So, if you're a young physicist graduating from high school with stars in your eyes,

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and you encounter freshman physics for the first time, watch out.

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If you have a rough time, that's the way it is.

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I started out my life as an experimental physicist, then I went to Harvard, and then I talked to my adviser,

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one of the world's greatest experimental physicists, Professor Pound,

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and he told me that maybe it's time to give it a rest.

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He said to me, "Your skills are much better suited to what you love the most,

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which is theory, mathematics, the world of higher dimensions."

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And I realized that he was probably right.

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The thing about physics, or even science that really intrigues me the most

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is to find the most fundamental basis for everything rather than trying to massage a theory or make a theory prettier,

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why not find out why it works, what makes it tick, and that's what I do for a living.

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I'm a theoretical physicist.

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Thank you very much.

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[Music]