B2 High-Intermediate 1897 Folder Collection
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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 distance… as 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 that “thing” 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” - “Magnetic” field, 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 says “hey, 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 electromagnetic “ripples” or “waves” travel 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 are “action 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.
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Real World Telekinesis (feat. Neil Turok)

1897 Folder Collection
Why Why published on March 29, 2013
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