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  • We normally think of Telekinesis as a kind of supernatural mental power, but the word

  • "Telekinesis" just comes from the greek kinēsis meaning "motion" and tele- meaning "at a distance".

  • And the real universe is full of telekinesis, or motion at a distance.

  • I mean, what tells a ball to fall down when you drop it? Why do magnets repel or attract

  • without touching? How does the sun heat us when it's millions of kilometers away? And

  • how do cell phones miraculously transport your voice to the other side of town or the

  • other side of the earth?

  • Well, the sad truth about all of these real-world Telekinetic phenomena is that they aren't

  • really action at a distanceas people figured out starting in the mid 1800s.

  • Before then, we didn't really know why magnets could repel or attract each other from far

  • away, how a ball could "know" that it was supposed to fall towards the earth, or how

  • the sun could light up the earth - we just knew that they did. And this was a kind of

  • spooky action at a distance.

  • But into the world of physics came a London bookbinder's apprentice named Michael Faraday

  • and a young Scottish laird named James Clerk Maxwell. Together Magnetic Mike and J.C. made

  • one of the greatest discoveries of all time. Faraday was convinced by his experiments that

  • magnetic and electric forces were not telekinetic action at a distance, but were really the

  • expression of some underlying physical... thing. He called thatthing” a field,

  • because it was away from the object - like students on a field trip away from school.

  • Inspired by the cleverness of this idea, Maxwell sat down with pencil and paper and put together

  • the experimental results with Faraday's hunch using beautiful mathematics: he showed that

  • you could describe all of electricity and magnetism with the idea of a field: a single,

  • Electro” - “Magneticfield, which permeates all of space.

  • The basic idea of a field as envisioned by Maxwell is that at every point in space there's

  • a number which tells you something about that point.

  • That number might be a simple number, like the temperature at that point, or the number

  • of cats at that point; or it might be a complicated number, like the direction and speed the wind

  • is blowing or the number of atoms of strawberry cheesecake that have moved past in the last

  • second. Make a chart of those numbers for every point in the universe, and that's what

  • a field is.

  • So young J.C. realized that at every point in space, in addition to a number telling

  • you the flow of strawberry cheesecake there, there are also numbers telling you the strength

  • and direction of the electromagnetic field. The mathematical equations he used to describe

  • these numbers also relate how the strength of the field at one point in space affects

  • the strength at nearby points, and those at their nearby points, and so on.

  • And it's this electromagnetic field (and the way it changes from point to point) that helps

  • explain how things like magnets and static electricity and your cell-phone calls can

  • have long-range effects without actually being telekinesis, or, action at a distance.

  • For example, a magnet generates a disturbance in the field that looks like... a magnetic

  • field. And when you move the magnet, Maxwell realized that the bits of the field close

  • to the magnet will change because the magnet changed its position. And then the bits of

  • the field a little farther away change because the field next to them changed. And then the

  • bits farther away, and even farther away, and so on like the tiniest bucket brigade

  • in the universe, until they eventually push on another magnet - maybe, a compass needle.

  • On the other hand, an electron makes a disturbance in the field that just sayshey, get away

  • from me!” to other electrons - but if you shake an electron around, it'll send out ripples

  • through the field like waves on a lake. The awesome thing that J.C. realized was that

  • these electromagneticripplesorwavestravel at the same speed as light. In fact...

  • they are light. J.C. had discovered that light is an electromagnetic wave!

  • And it's these waves which are the bucket brigade that transmits heat from the sun to

  • the earth or a signal from your cell phone to your mother's or light from a lightbulb

  • to your eye. The only reason we think any of these things areaction at a distance

  • is that we can't see the hidden bucket brigade going on under our very noses. But it's there,

  • as countless experiments since Faraday's have shown.

  • And so, Magnetic Mike and J.C. and their description of electromagnetic fields explained magnets

  • and electricity and light without any need for telekinesis or other kinds of action at

  • a distance. In the process, they laid the foundations for all of 20th century physics

  • - because today, fields are the cornerstone of our understanding of the universe.

We normally think of Telekinesis as a kind of supernatural mental power, but the word

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B2 field distance electromagnetic magnet faraday magnetic

Real World Telekinesis (feat. Neil Turok)

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    Why Why posted on 2013/03/29
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