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動画の字幕をクリックしてすぐ単語の意味を調べられます！
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It turns out the strongest material in the universe isn't steel, it isn't graphene,
and it's not even that ever-so fictional vibranium.
It's….pasta?
Nuclear pasta to be exact.
Ok it's not actually pasta, but it is a material so dense that it's approximately
10 billion times stronger than steel.
And yes, scientists have named it after their favorite food.
It all has to do with neutron stars.
A neutron star is what's left after a massive star explodes into a supernova--it's essentially
the small, leftover, burnt-out core of that explosion--maybe 20 kilometers wide, extremely dense, and collapsing in on itself.
The inner part of the star actually collapses so much that some of its electrons and protons
get squeezed together to form more neutrons...hence the name 'neutron star'.
The density part is key here--neutron stars are so dense that a single teaspoon of them would weigh a billion tons.
So if you were to dig about a kilometer below the surface of a neutron star, what do you think you'd find?
New scientific work has simulated just that.
The pressure inside a neutron star is so extreme that the material inside clumps together in
unique patterns, many of which are vaguely reminiscent of pasta shapes...which is what they're named after.
You've got your gnocchi, which looks like little blobs, and its inverse, the anti gnocchi.
Long string-like tubes are called spaghetti and anti spaghetti, there's the good old
sheet-like lasagna, and….waffles?
That's a little outside the pasta family, but I'll take it.
These shapes were unveiled via computer simulation, since such high pressures and the resulting
high densities are very difficult to replicate here on earth.
Previous work had already demonstrated that the surface of a neutron star is incredibly
strong, but these new simulations show that the nuclear pasta that lies beneath is even stronger.
A 2013 publication had hypothesized that nuclear pasta exists, but there were no simulations
at the time that could show us what it was like.
These new findings reveal a high level of detail about the shape and nature of nuclear
pasta, and suggest that the shapes are actually quite disorderly and complex.
Why does this matter?
Well, neutron stars spin.
The explosion of the massive star that will eventually become the neutron star gives the
whole thing a rotation, and as the neutron star collapses, that rotation gets even faster.
This spinning means that neutron stars may be emitting gravitational waves--ripples in
spacetime that we could potentially detect.
Here's where the nuclear pasta becomes important--neutron stars would only generate gravitational waves
as they spin if their crusts have some kind of irregularity.
The experts in this field call bumps on the surface of a neutron star 'mountains',
even though they're only a couple of centimeters tall.
These lumps would be caused by mounds of dense materials inside the star.
Sounds like gnocchi to me!
So if nuclear pasta does indeed exist the way scientists have now simulated it, that
would mean neutron stars are generating gravitational all the time!
So, this is where real-world observation and simulation come together.
The various nuclear pasta types proposed by this research could be the reason behind neutron
stars creating gravitational waves.
Scientists think that these 'mountains' on the stars' surface need to be pretty
big (by neutron star mountain standards) to produce waves we can detect.
These new details about nuclear pasta's nature reveal that the pasta could be causing
'mountains' tens of centimeters tall, big enough that we could spot them with the
observational equipment we already have--like LIGO.
And observing the gravitational waves of neutron stars would, in turn, experimentally confirm
the existence of nuclear pasta--which is quite probably the strongest known material in the universe.
Sorry, vibranium.
For your updates on exciting space hardware, watch this video to learn more about the delay
in the James Webb Space Telescope, and subscribe to Seeker for more SPACE.
Thanks for watching.
コツ：単語をクリックしてすぐ意味を調べられます！

読み込み中…

中級 米

We May Have Just Found the Strongest Material in the Universe

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Jerry Liu 2019 年 5 月 23 日 に公開

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