Is it possible to create a perfect vacuum? - Rolf Landua and Anais Rassat

1,095,274 views ใƒป 2017-09-12

TED-Ed


ืื ื ืœื—ืฅ ืคืขืžื™ื™ื ืขืœ ื”ื›ืชื•ื‘ื™ื•ืช ื‘ืื ื’ืœื™ืช ืœืžื˜ื” ื›ื“ื™ ืœื”ืคืขื™ืœ ืืช ื”ืกืจื˜ื•ืŸ.

ืชืจื’ื•ื: Ido Dekkers ืขืจื™ื›ื”: Sigal Tifferet
00:06
The universe is bustling with matter and energy.
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ื”ื™ืงื•ื ืจื•ื—ืฉ ื—ื•ืžืจ ื•ืื ืจื’ื™ื”.
00:09
Even in the vast apparent emptiness of intergalactic space,
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ืืคื™ืœื• ื‘ืจื™ืงื ื•ืช ืœื›ืื•ืจื” ื‘ืžืจื—ื‘ ื”ื‘ื™ืŸ ื’ืœืงื˜ื™,
00:12
there's one hydrogen atom per cubic meter.
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ื™ืฉ ืื˜ื•ื ืžื™ืžืŸ ืื—ื“ ืœืžื˜ืจ ืจื‘ื•ืข.
00:14
That's not the mention a barrage of particles
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ื•ื–ื” ื‘ืœื™ ืœื”ืชื™ื™ื—ืก ืœื—ืœืงื™ืงื™ื
00:17
and electromagnetic radiation
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ื•ืงืจื™ื ื” ืืœื˜ืจื•ืžื’ื ื˜ื™ืช
00:19
passing every which way from stars, galaxies, and into black holes.
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ืฉืขื•ื‘ืจื™ื ืœื›ืœ ื›ื™ื•ื•ืŸ ืžื›ื•ื›ื‘ื™ื, ื’ืœืงืกื™ื•ืช, ื•ืœืชื•ืš ื—ื•ืจื™ื ืฉื—ื•ืจื™ื.
00:23
There's even radiation left over from the Big Bang.
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ื™ืฉ ืืคื™ืœื• ืงืจื™ื ื” ืฉื ืฉืืจื” ืžื”ืžืคืฅ ื”ื’ื“ื•ืœ.
00:26
So is there such thing as a total absence of everything?
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ืื– ื”ืื ื™ืฉ ื“ื‘ืจ ื›ื–ื” ื—ื•ืกืจ ื›ืœืœื™ ื‘ื”ื›ืœ?
00:30
This isn't just a thought experiment.
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ื–ื” ืœื ืจืง ื ื™ืกื•ื™ ืžื—ืฉื‘ืชื™.
00:32
Empty spaces, or vacuums, are incredibly useful.
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ื—ืœืœื™ื ืจื™ืงื™ื, ืื• ื•ืืงื•ื, ื”ื ืžืื•ื“ ืฉื™ืžื•ืฉื™ื™ื.
00:36
Inside our homes, most vacuum cleaners work
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ื‘ืชื•ืš ื”ื‘ืชื™ื ืฉืœื ื•, ืจื•ื‘ ืฉื•ืื‘ื™ ื”ืื‘ืง ืขื•ื‘ื“ื™ื
00:38
by using a fan to create a low-pressure relatively empty area
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ืขืœ ื™ื“ื™ ืฉื™ืžื•ืฉ ื‘ืžืื•ื•ืจืจ ื›ื“ื™ ืœื™ืฆื•ืจ ืื™ื–ื•ืจ ืจื™ืง ืขื ืœื—ืฅ ื ืžื•ืš ื™ื—ืกื™ืช
00:42
that sucks matter in to fill the void.
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ืฉืฉื•ืื‘ ื—ื•ืžืจ ื›ื“ื™ ืœืžืœื ืืช ื”ื—ืœืœ.
00:45
But that's far from empty.
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ืื‘ืœ ื–ื” ืจื—ื•ืง ืžืื•ื“ ืžืจื™ืง.
00:47
There's still plenty of matter bouncing around.
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ื™ืฉ ืขื“ื™ื™ืŸ ื”ืจื‘ื” ื—ื•ืžืจ ืฉื–ื– ืœื›ืœ ื”ื›ื™ื•ื•ื ื™ื.
00:49
Manufacturers rely on more thorough, sealed vacuums
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ื™ืฆืจื ื™ื ืžืกืชืžื›ื™ื ืขืœ ื•ืืงื•ื ื™ื•ืชืจ ืื˜ื•ื ื•ืžืฉืžืขื•ืชื™
00:52
for all sorts of purposes.
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ืœื›ืœ ืžื™ื ื™ ืกื•ื’ื™ื ืฉืœ ืžื˜ืจื•ืช.
00:54
That includes vacuum-packed food that stays fresh longer,
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ื–ื” ื›ื•ืœืœ ืื•ื›ืœ ืฉืืจื•ื– ื‘ื•ืืงื•ื ืฉื ืฉืืจ ื˜ืจื™ ื™ื•ืชืจ ื–ืžืŸ,
00:57
and the vacuums inside early light bulbs that protected filaments from degrading.
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ื•ื”ื•ืืงื•ื ื‘ืชื•ืš ื ื•ืจื•ืช ืžื•ืงื“ืžื•ืช ืฉืžื ืข ืžื—ื•ื˜ ื”ืœื”ื˜ ืœื”ืฉืจืฃ.
01:02
These vacuums are generally created with some version
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ื”ื•ืืงื•ืžื™ื ื”ืืœื” ื‘ืื•ืคืŸ ื›ืœืœื™ ื ื•ืฆืจื™ื ืขื ื›ืžื” ื’ืจืกืื•ืช
01:05
of what a vacuum cleaner does
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ืฉืœ ืžื” ืฉืฉื•ืื‘ื™ ืื‘ืง ืขื•ืฉื™ื
01:07
using high-powered pumps that create enough suction
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ื‘ืฉื™ืžื•ืฉ ื‘ืžืฉืื‘ื•ืช ื—ื–ืงื•ืช ืฉื™ื•ืฆืจื•ืช ืžืกืคื™ืง ืฉืื™ื‘ื”
01:10
to remove as many stray atoms as possible.
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ื›ื“ื™ ืœื”ื•ืฆื™ื ื›ืžื” ืฉื™ื•ืชืจ ืื˜ื•ืžื™ื ืžืฉื•ื˜ื˜ื™ื ืฉืืคืฉืจ.
01:12
But the best of these industrial processes
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ืื‘ืœ ื’ื ื”ื˜ื•ื‘ื™ื ื‘ืชื”ืœื™ื›ื™ื ื”ืชืขืฉื™ื™ืชื™ื™ื ื”ืืœื”
01:15
tends to leave hundreds of millions of atoms
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ื ื•ื˜ื™ื ืœื”ืฉืื™ืจ ืžืื•ืช ืžืœื™ื•ื ื™ ืื˜ื•ืžื™ื
01:17
per cubic centimeter of space.
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ืœืกื ื˜ื™ืžื˜ืจ ืžืขื•ืงื‘ ืฉืœ ื—ืœืœ.
01:19
That isn't empty enough for scientists who work on experiments,
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ื–ื” ืœื ืจื™ืง ืžืกืคื™ืง ืœืžื“ืขื ื™ื ืฉืขื•ื‘ื“ื™ื ืขืœ ื ื™ืกื•ื™ื™ื,
01:22
like the Large Hadron Collider,
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ื›ืžื• ืžืจืกืง ื”ื”ื“ืจื•ื ื™ื ื”ื’ื“ื•ืœ,
01:24
where particle beams need to circulate at close to the speed of light
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ื‘ื• ืืœื•ืžื•ืช ื—ืœืงื™ืงื™ื ืฆืจื™ื›ื•ืช ืœื”ืงื™ืฃ ืงืจื•ื‘ ืœืžื”ื™ืจื•ืช ื”ืื•ืจ
01:27
for up to ten hours without hitting any stray atoms.
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ืขื“ 10 ืฉืขื•ืช ื‘ืœื™ ืœืคื’ื•ืข ื‘ืืฃ ืื˜ื•ื ืชื•ืขื”.
01:31
So how do they create a vacuum?
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ืื– ืื™ืš ื”ื ื™ื•ืฆืจื™ื ื•ืืงื•ื?
01:33
The LHC's pipes are made of materials, like stainless steel,
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ืฆื™ื ื•ืจื•ืช ื” LHC ืขืฉื•ื™ื™ื ืžื—ื•ืžืจ ื›ืžื• ืคืœื“ืช ืืœ ื—ืœื“,
01:36
that don't release any of their own molecules
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ืฉืœื ืžืฉื—ืจืจืช ืืฃ ืื—ืช ืžื”ืžื•ืœืงื•ืœื•ืช ืฉืœื”
01:38
and are lined with a special coating to absorb stray gases.
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ื•ืžืฆื•ืคื” ื‘ืฆื™ืคื•ื™ ืžื™ื•ื—ื“ ื›ื“ื™ ืœืกืคื•ื’ ื’ื–ื™ื ืชื•ืขื™ื.
01:42
Raising the temperature to 200 degrees Celsius
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ื”ืขืœืืช ื”ื˜ืžืคืจื˜ื•ืจื” ืœ 200 ืžืขืœื•ืช
01:45
burns off any moisture,
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ืฉื•ืจืคืช ืืช ื›ืœ ื”ืœื—ื•ืช,
01:46
and hundreds of vacuum pumps take two weeks to trap enough gas and debris
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ื•ืžืื•ืช ืžืฉืื‘ื•ืช ื•ืืงื•ื ื“ื•ืจืฉื•ืช ืฉื‘ื•ืขื™ื™ื ืœื”ื•ืฆื™ื ืžืกืคื™ืง ื’ื– ื•ืคืกื•ืœืช
01:50
out of the pipes for the collider's incredibly sensitive experiments.
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ืžื—ื•ืฅ ืœืฆื™ื ื•ืจื•ืช ืขื‘ื•ืจ ื”ื ื™ืกื•ื™ื™ื ื”ืžืื•ื“ ืจื’ื™ืฉื™ื ืฉืœ ื”ืžืื™ืฅ.
01:54
Even with all this,
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ืขื ื›ืœ ื–ื”,
01:56
the Large Hadron Collider isn't a perfect vacuum.
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ื‘ืžืจืกืง ื”ื”ื“ืจื•ื ื™ื ื”ื’ื“ื•ืœ ืื™ืŸ ื•ื•ืืงื•ื ืžื•ืฉืœื.
01:59
In the emptiest places, there are still
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ื‘ืžืงื•ืžื•ืช ื”ื›ื™ ืจื™ืงื™ื, ืขื“ื™ื™ืŸ ื™ืฉ
02:01
about 100,000 particles per cubic centimeter.
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ื‘ืขืจืš 100,000 ื—ืœืงื™ืงื™ื ืœืกื ื˜ื™ืžื˜ืจ ืžืขื•ืงื‘.
02:05
But let's say an experiment like that could somehow get every last atom out.
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ืื‘ืœ ื‘ื•ืื• ื ื’ื™ื“ ืฉื ื™ืกื•ื™ ื›ื–ื” ื™ื•ื›ืœ ืื™ื›ืฉื”ื• ืœื”ื•ืฆื™ื ื›ืœ ืื˜ื•ื ื•ืื˜ื•ื.
02:09
There's still an unfathomably huge amount of radiation all around us
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ื™ืฉ ืขื“ื™ื™ืŸ ื›ืžื•ืช ื‘ืœืชื™ ื ื™ืชื ืช ืœืชืคื™ืฉื” ืฉืœ ืงืจื™ื ื” ืกื‘ื™ื‘ื ื•
02:13
that can pass right through the walls.
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ืฉื™ื›ื•ืœื” ืœืขื‘ื•ืจ ื™ืฉืจ ื“ืจืš ืงื™ืจื•ืช.
02:15
Every second, about 50 muons from cosmic rays,
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ื›ืœ ืฉื ื™ื”, ื‘ืขืจืš 50 ืžื•ืื•ื ื™ื ืžืงืจื ื™ื™ื ืงื•ืกืžื™ื•ืช,
02:18
10 million neutrinos coming directly from the Big Bang,
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10 ืžืœื™ื•ืŸ ื ื™ื•ื˜ืจื™ื ื• ืฉืžื’ื™ืขื™ื ื™ืฉื™ืจื•ืช ืžื”ืžืคืฅ ื”ื’ื“ื•ืœ,
02:21
30 million photons from the cosmic microwave background,
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30 ืžืœื™ื•ืŸ ืคื•ื˜ื•ื ื™ื ืžืงืจื™ื ืช ื”ืจืงืข ื”ืงื•ืกืžื™ืช,
02:25
and 300 trillion neutrinos from the Sun pass through your body.
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ื• 300 ื˜ืจื™ืœื™ื•ืŸ ื ื™ื•ื˜ืจื™ื ื• ืžื”ืฉืžืฉ ืขื•ื‘ืจื™ื ื“ืจืš ื”ื’ื•ืฃ ืฉืœื›ื.
02:29
It is possible to shield vacuum chambers with substances,
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ืืคืฉืจ ืœื”ื’ืŸ ืขืœ ืชืื™ ื•ืืงื•ื ืขื ื—ื•ืžืจื™ื,
02:32
including water,
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ื›ื•ืœืœ ืžื™ื,
02:33
that absorb and reflect this radiation,
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ืฉืกื•ืคื’ื™ื ื•ืžื—ื–ื™ืจื™ื ืืช ื”ืงืจื™ื ื”,
02:36
except for neutrinos.
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ื—ื•ืฅ ืžื ื™ื•ื˜ืจื™ื ื•.
02:37
Let's say you've somehow removed all of the atoms
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ื‘ื•ืื• ื ื’ื™ื“ ืฉืื™ื›ืฉื”ื• ื ื•ืฆื™ื ืืช ื›ืœ ื”ืื˜ื•ืžื™ื
02:40
and blocked all of the radiation.
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ื•ื ื—ืกื•ื ืืช ื›ืœ ื”ืงืจื™ื ื”.
02:42
Is the space now totally empty?
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ื”ืื ื”ื—ืœืœ ืจื™ืง ืœื—ืœื•ื˜ื™ืŸ ืขื›ืฉื™ื•?
02:44
Actually, no.
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ืœืžืขืฉื”, ืœื.
02:45
All space is filled with what physicists call quantum fields.
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ื›ืœ ื”ื—ืœืœ ืžืœื ืžื” ืฉืžื“ืขื ื™ื ืงื•ืจืื™ื ืœื• ืฉื“ื•ืช ืงื•ื•ืื ื˜ื™ื™ื.
02:49
What we think of as subatomic particles,
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ืžื” ืฉืื ื—ื ื• ื—ื•ืฉื‘ื™ื ืขืœื™ื• ื›ื—ืœืงื™ืงื™ื ืชืช ืื˜ื•ืžื™ื™ื,
02:51
electrons and photons and their relatives,
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ืืœืงื˜ืจื•ื ื™ื ื•ืคื•ื˜ื•ื ื™ื ื•ื”ืงืจื•ื‘ื™ื ืฉืœื”ื,
02:53
are actually vibrations in a quantum fabric
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ื”ื ืœืžืขืฉื” ืจื˜ื™ื˜ื•ืช ื‘ืžืืจื’ ื”ืงื•ื•ืื ื˜ื™
02:56
that extends throughout the universe.
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ืฉืคืจื•ืฉ ื‘ื›ืœ ื”ื™ืงื•ื.
02:58
And because of a physical law called the Heisenberg Principle,
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ื•ื‘ื’ืœืœ ื—ื•ืง ืคื™ืกื™ืงืœื™ ืฉื ืงืจื ืขื™ืงืจื•ืŸ ื”ื™ื™ื–ื ื‘ืจื’,
03:01
these fields never stop oscillating,
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ื”ืฉื“ื•ืช ื”ืืœื” ืืฃ ืคืขื ืœื ืžืคืกื™ื“ื™ื ืœืจื˜ื•ื˜,
03:03
even without any particles to set off the ripples.
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ืืคื™ืœื• ื‘ืœื™ ื—ืœืงื™ืงื™ื ืฉื™ืชื—ื™ืœื• ืืช ื”ื’ืœื™ื.
03:06
They always have some minimum fluctuation called a vacuum fluctuation.
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ืชืžื™ื“ ื™ืฉ ืœื”ื ื›ืžื” ืจื˜ื™ื˜ื•ืช ืžื™ื ื™ืžืœื™ื•ืช ืฉื ืงืจืื•ืช ืจื˜ื™ื˜ื•ืช ื•ืืงื•ื.
03:10
This means they have energy, a huge amount of it.
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ื–ื” ืื•ืžืจ ืฉื™ืฉ ืœื”ื ืื ืจื’ื™ื”, ื›ืžื•ืช ืขืฆื•ืžื” ืžืžื ื”.
03:13
Because Einstein's equations tell us that mass and energy are equivalent,
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ื‘ื’ืœืœ ืฉื”ืžืฉื•ื•ืื•ืช ืฉืœ ืื™ื™ื ืฉื˜ื™ื™ืŸ ืื•ืžืจื•ืช ืœื ื• ืฉืžืืกื” ื•ืื ืจื’ื™ื” ื”ื ืฉืงื•ืœื™ื,
03:17
the quantum fluctuations in every cubic meter of space
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ืœืจื˜ื™ื˜ื•ืช ื”ืงื•ื•ืื ื˜ื™ื•ืช ื‘ื›ืœ ืžื˜ืจ ืจื‘ื•ืข ืฉืœ ื—ืœืœ
03:20
have an energy that corresponds to a mass of about four protons.
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ื™ืฉ ืื ืจื’ื™ื” ืฉืฉื•ื” ืœืžืืกื” ืฉืœ ื‘ืขืจืš ืืจื‘ืขื” ืคืจื•ื˜ื•ื ื™ื.
03:24
In other words, the seemingly empty space inside your vacuum
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ื‘ืžื™ืœื™ื ืื—ืจื•ืช, ื”ื—ืœืœ ืฉื ืจืื” ืจื™ืง ื‘ืชื•ืš ื”ื•ืืงื•ื ืฉืœื›ื
03:27
would actually weigh a small amount.
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ื™ืฉืงื•ืœ ืœืžืขืฉื” ืžืขื˜.
03:30
Quantum fluctuations have existed since the earliest moments of the universe.
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ืจื˜ื™ื˜ื•ืช ืงื•ื•ืื ื˜ื™ื•ืช ื”ื™ื• ืงื™ื™ืžื•ืช ืžืื– ื”ืจื’ืขื™ื ื”ืจืืฉื•ื ื™ื ืฉืœ ื”ื™ืงื•ื.
03:34
In the moments after the Big Bang,
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ื‘ืจื’ืขื™ื ืื—ืจื™ ื”ืžืคืฅ ื”ื’ื“ื•ืœ,
03:36
as the universe expanded,
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ื›ืฉื”ื™ืงื•ื ื”ืชืจื—ื‘,
03:38
they were amplified and stretched out to cosmic scales.
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ื”ื ื”ืชื’ื‘ืจื• ื•ื ืžืชื—ื• ื‘ืงื ื” ืžื™ื“ื” ืงื•ืกืžื™.
03:42
Cosmologists believe that these original quantum fluctuations
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ืงื•ืกืžื•ืœื•ื’ื™ื ืžืืžื™ื ื™ื ืฉื”ืจื˜ื™ื˜ื•ืช ื”ืงื•ื•ืื ื˜ื™ื•ืช ื”ืžืงื•ืจื™ื•ืช ื”ืืœื•
03:45
were the seeds of everything we see today:
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ื”ื™ื• ื”ืžืงื•ืจ ืœื›ืœ ืžื” ืฉืื ื—ื ื• ืจื•ืื™ื ื”ื™ื•ื:
03:48
galaxies and the entire large scale structure of the universe,
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ื’ืœืงืกื™ื•ืช ื•ืžื‘ื ื™ื ืฉืœืžื™ื ื‘ืงื ื” ืžื™ื“ื” ืขืฆื•ื ืฉืœ ื”ื™ืงื•ื,
03:51
as well as planets and solar systems.
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ื›ืžื• ื’ื ืคืœื ื˜ื•ืช ื•ืžืขืจื›ื•ืช ื›ื•ื›ื‘ื™ื.
03:54
They're also the center of one of the greatest scientific mysteries of our time
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ื”ืŸ ื’ื ื‘ืžืจื›ื–ื” ืฉืœ ืื—ืช ื”ืชืขืœื•ืžื•ืช ื”ื›ื™ ื’ื“ื•ืœื•ืช ืฉืœ ื”ืžื“ืข
03:58
because according to the current theories,
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ื›ื™ ืœืคื™ ื”ืชืื•ืจื™ื•ืช ื”ื ื•ื›ื—ื™ื•ืช,
04:01
the quantum fluctuations in the vacuum of space
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ื”ืจื˜ื™ื˜ื•ืช ื”ืงื•ื•ืื ื˜ื™ื•ืช ื‘ื•ืืงื•ื ืฉืœ ื”ื—ืœืœ
04:03
ought to have 120 orders of magnitude more energy than we observe.
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ืฆืจื™ื›ื•ืช ืœื”ื™ื•ืช ืื ืจื’ื˜ื™ื•ืช ื‘ 120 ืงื ื™ ืžื™ื“ื” ืžืžื” ืฉืื ื—ื ื• ืจื•ืื™ื.
04:08
Solving the mystery of that missing energy
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ืคืชื™ืจืช ื”ืชืขืœื•ืžื” ื”ื–ื• ืฉืœ ื”ืื ืจื’ื™ื” ื”ื—ืกืจื”
04:10
may entirely rewrite our understanding of physics and the universe.
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ืื•ืœื™ ืชืฉื›ืชื‘ ืœื’ืžืจื™ ืืช ื”ื”ื‘ื ื” ืฉืœื ื• ืฉืœ ื”ืคื™ื–ื™ืงื” ื•ื”ื™ืงื•ื.
ืขืœ ืืชืจ ื–ื”

ืืชืจ ื–ื” ื™ืฆื™ื’ ื‘ืคื ื™ื›ื ืกืจื˜ื•ื ื™ YouTube ื”ืžื•ืขื™ืœื™ื ืœืœื™ืžื•ื“ ืื ื’ืœื™ืช. ืชื•ื›ืœื• ืœืจืื•ืช ืฉื™ืขื•ืจื™ ืื ื’ืœื™ืช ื”ืžื•ืขื‘ืจื™ื ืขืœ ื™ื“ื™ ืžื•ืจื™ื ืžื”ืฉื•ืจื” ื”ืจืืฉื•ื ื” ืžืจื—ื‘ื™ ื”ืขื•ืœื. ืœื—ืฅ ืคืขืžื™ื™ื ืขืœ ื”ื›ืชื•ื‘ื™ื•ืช ื‘ืื ื’ืœื™ืช ื”ืžื•ืฆื’ื•ืช ื‘ื›ืœ ื“ืฃ ื•ื™ื“ืื• ื›ื“ื™ ืœื”ืคืขื™ืœ ืืช ื”ืกืจื˜ื•ืŸ ืžืฉื. ื”ื›ืชื•ื‘ื™ื•ืช ื’ื•ืœืœื•ืช ื‘ืกื ื›ืจื•ืŸ ืขื ื”ืคืขืœืช ื”ื•ื•ื™ื“ืื•. ืื ื™ืฉ ืœืš ื”ืขืจื•ืช ืื• ื‘ืงืฉื•ืช, ืื ื ืฆื•ืจ ืื™ืชื ื• ืงืฉืจ ื‘ืืžืฆืขื•ืช ื˜ื•ืคืก ื™ืฆื™ืจืช ืงืฉืจ ื–ื”.

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