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  • One of the grandest scientific tools ever made by mankind

  • is called an atom smasher.

  • And I mean literally grand.

  • The biggest one ever built,

  • the Large Hadron Collider, or LHC,

  • is a ring with a circumference of about 18 miles.

  • That's more than the entire length of Manhattan.

  • So what is an atom smasher?

  • It is a device that collides atomic nuclei together

  • at extremely high energy.

  • The most powerful one scientists have ever built

  • can heat matter to the hottest temperatures ever achieved,

  • temperatures last seen at a trillionth of second

  • after the universe began.

  • Our accelerators are full of engineering superlatives.

  • The beam-containing region of the LHC is a vacuum,

  • with lower pressure than what surrounds

  • the international space station,

  • and is 456 degrees Fahrenheit below zero,

  • colder than the temperature of deepest space.

  • A previous accelerator sitting in the LHC tunnel

  • holds the world record for velocity,

  • accelerating an electron to a speed so fast

  • that if it were to race a photon of light,

  • it would take about 14 minutes for the photon

  • to get a lead of about 10 feet.

  • If that doesn't impress you,

  • remember the photon is fastest thing in the universe,

  • it goes about 186,000 miles per second.

  • So how do these subatomic particle accelerators work?

  • Well, they use electric fields.

  • Electric fields make charged particles move in the same way

  • that gravity will pull a dropped baseball.

  • The force from the electric field

  • will pull a particle to make it move.

  • The speed will continue to increase

  • until the charged particle is moving incredibly fast.

  • A simple particle accelerator can be made

  • by hooking two parallel metal plates to a battery.

  • The charge from the battery moves

  • on to the two metal plates

  • and makes an electric field that pulls the particle along.

  • And that's it,

  • you got a particle accelerator.

  • The problem is that an accelerator built this way is very weak.

  • Building a modern accelerator like the LHC this way

  • would take over five trillion standard D-cell batteries.

  • So scientists use much stronger batteries

  • and put them one after another.

  • An earlier accelerator used this method

  • and was about a mile long

  • and was equivalent to 30 billion batteries.

  • However, to make an accelerator

  • that is equivalent to five trillion batteries

  • would require an accelerator 150 miles long.

  • Scientists needed another way.

  • While electric fields would make a particle go faster,

  • magnetic fields make them move in a circular path.

  • If you put an electric field along the circle,

  • you don't need to use miles of electric fields,

  • you can use a single electric field over and over again.

  • The beams go around the circle,

  • and each time they gain more energy.

  • So very high-energy accelerators consist of

  • a short region with accelerating electric fields,

  • combined with long series of magnets

  • that guide the particles in a circle.

  • The strength of the magnets

  • and the radius of the circular path

  • determines the maximum energy of the beam.

  • Once the beam is zooming along,

  • then the real fun begins,

  • the smashing.

  • The reason physicists want to get

  • those particles moving so fast

  • is so that they can slam them into one another.

  • These collisions can teach us

  • about the fundamental rules that govern matter,

  • but they'd be impossible without the feat of engineering

  • that is the particle accelerator.

One of the grandest scientific tools ever made by mankind

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B1 中級

TED-ED】原子を粉砕する粒子加速器の仕組みとは?- ドン・リンカーン (【TED-Ed】How does an atom-smashing particle accelerator work? - Don Lincoln)

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    wikiHuang に公開 2021 年 01 月 14 日
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