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What's inside a black hole?
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Black holes are mysterious and bizarre objects in the universe that really have no explanation.
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In fact, we hardly know anything about what lies inside of a black hole?
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We know and understand what we see on the outside of a black hole
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But we have no way of going inside one to take a look at what is really happening.
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Even if we sent a probe inside a black hole,
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it would not survive the journey.
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And there would be no way that the probe could transmit a signal outside once it had been sucked inside.
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This is because a black hole is the product of mass being squeezed together, so densely and so tightly that it creates a gravitational pole.
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That is so strong that not even light can escape its grasp.
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Supermassive black holes with masses millions to billions of times that of the Sun are thought to lurk at the hearts of all galaxies in the universe.
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You may notice that when you see a photo of a spiral galaxy
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such as the Milky Way in the center of the galaxy is a giant mass of light?
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Which many people would think looks like a massive Sun, but this is not light coming from the black hole itself.
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Remember that life cannot escape the heavy gravitational pull.
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Instead the light we see comes from magnetic fields near a spinning black hole that propel electrons outward in a jet
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Along the rotation axis the electrons produce bright radio waves.
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Quasars are believed to produce their energy from massive black holes in the center of the galaxies in which the quasars are located.
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But quasars are so bright they drown out the light from all the other stars in the same galaxy. You're probably asking well
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What's a quasar a quasar is the short name for quasi stellar object and is a very highly energetic object?
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Surrounding an actively feeding supermassive black hole in more basic terms the supermassive black hole in the middle of a galaxy feeds
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intermittently as it feeds gas swirls around it at incredible speeds and
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Forms an insanely bright hot orbiting disc and if the black hole is swallowing a large amount of material this feeding is accomplished by gigantic jets of gas these are called quasar
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They are essentially fueled by the black holes they orbit
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some supermassive black hole giants release an extraordinarily
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Large amount of light when they rip apart stars in devour matter and are likely the driving force behind these quasars
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When material gets too close to a black hole it forms that bright hot accretion disk around the black hole
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That accretion disk heats up to millions of degrees
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Blasting out an enormous amount of radiation
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The magnetic environment around the black hole forms twin Jets of material which flow out into space for millions of light years
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This becomes what is called an active galactic nucleus
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Or a GN the diet of known black holes consists mostly of gas and dust which fill the otherwise empty space throughout the universe
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black holes can also consume material torn from nearby stars in fact the most massive black holes can swallow stars whole
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Black holes can also grow by colliding and merging with other black holes
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This growth process is what can and usually does reveal the presence of a black hole?
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But supermassive black holes aren't always feeding if a black hole runs out of food the Jets run out of power and shut down
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Right up until something gets too close and the whole system starts up again the supermassive black hole at the center of our Milky Way
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Galaxy is all out of food or space material to consume
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It lies completely dormant for the time being a sleeping giant, so it doesn't have an active galactic nucleus
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And so there is no quasar emitting light however
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We are on a collision course with another galaxy and in 10 billion years or so when the Milky Way collides with the Andromeda galaxy
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Our supermassive black hole may roar back to life as a quasar as it begins to consume part of this new galaxy
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Now it might sound like black holes are dangerous and that anything that even remotely comes close to a black hole
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Would get sucked inside and be crushed and while it's true that if you manage to carefully drop an object into a black hole
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You'd never get that object back, but black holes are actually remarkably bad at pulling material close to them
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There are a couple of reasons for this one black holes aren't actually attractive to anything for any reason other than gravity
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Much like our solar system is in a stable orbits around the Sun the vast
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majority of a galaxy is in a stable orbit around the black hole with no real reason to go plunging towards the very center of
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The galaxy the second reason that black holes are bad at being astronomical vacuum cleaners is that they're really?
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Really inefficient at getting material close enough to them to cross the event horizon and add to the mass of the black hole
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Even small black holes which exist in great numbers in the galaxy are much better at tearing a companion star apart than they aren't actually
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Growing their own size by consuming the star hole so despite their reputation
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Black holes will not actually suck in objects from large distances a black hole can only capture objects that come very close to it
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They're more like venus flytraps than cosmic vacuum cleaners for example imagine replacing the Sun by a black hole of the same mass
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permanent darkness would fall on earth
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But the planets would continue to revolve around the black hole at the same distance and speed as they do now
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None of the planets would be sucked into the black hole our earth would be in danger
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Only if it came within some 10 miles of the black hole
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Much less than the actual distance of the Earth from the Sun which is a comforting 93 million miles away
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So after knowing all of this do we have any idea, what is inside of a black hole?
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Current theories predict that all the matter in a black
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Hole is piled up in a single point at the center
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But we do not understand how this central singularity works to properly understand the black hole center requires a fusion of the theory of gravity
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With the theory that describes the behavior of matter on the smallest scales called quantum mechanics
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This unifying theory has already been given a name quantum gravity, but how it works is still unknown
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This is one of the most important unsolved problems in physics
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Studies of black holes may one day provide the key to unlock this mystery
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Einstein's theory of general relativity allows unusual characteristics for black holes
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For example the central singularity might form a bridge to another universe. This is similar to a so-called wormhole
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Which is a mysterious solution of Einstein's equations that has no event horizon?
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Bridges and wormholes might allow travel to other universes or even time travel, but without observational and experimental data
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This is mostly speculation
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We do not know whether bridges or wormholes exist in the universe or could even have formed in principle
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By contrast black holes have been observed to exist and we understand how they form
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What is actually inside of a black Cole is still a mystery?
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So does a black hole live forever if there is nothing for a black hole to consume then no in
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Fact a very surprising thing happens you might have heard of Stephen Hawking
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He is a theoretical physicist in cosmologists, and is at the forefront on the study of black holes
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He came up with a theoretical prediction that black holes emit radiation this of course is now known as Hawking radiation
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Hawking radiation reduces the mass and energy of black holes and is therefore also known as black hole evaporation
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Because of this black holes that do not gain mass through other means are expected to shrink and ultimately vanish
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What it means is that if the black hole has nothing to eat it?
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Eventually evaporates the energy and mass that the black hole pulled inside of itself
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Evaporates back out into space in the form of radiation. It is almost as if a black
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Hole is a universe recycling machine Stephen Hawking proved this in
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1974 by using the laws of quantum mechanics to study the region close to a black hole horizon
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The quantum theory describes the behavior of matter on the smallest scales it predicts that tiny particles and light are
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continuously created and destroyed on subatomic scales
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Some of the light thus created actually has a very small chance of escaping before it is destroyed to an outsider
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It is as though the event horizon glows the energy carried away by the glow decreases the black hole's mass until it is completely gone
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This surprising new insight show that there is still much to learn about black holes
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However, Hawking's glow is completely irrelevant for any of the black holes known to exist in the universe
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For them the temperature of the glow is almost zero and the energy loss is negligible
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The time needed for the black holes to lose much of their mass is
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unimaginably long however if much smaller black holes ever existed in the universe
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Then Hawking's findings would have been catastrophic a black
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hole as massive as a cruise ship would disappear in a bright flash in less than a second as
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You can see black holes are incredible and mysterious things perhaps one day
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We will know exactly what lies inside of a black
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Hole, maybe we will find out that they are gates to another dimension such as wormholes
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Or maybe we will never know and just come to accept their existence as they are