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  • What's inside a black hole?

  • Black holes are mysterious and bizarre objects in the universe that really have no explanation.

  • In fact, we hardly know anything about what lies inside of a black hole?

  • We know and understand what we see on the outside of a black hole

  • But we have no way of going inside one to take a look at what is really happening.

  • Even if we sent a probe inside a black hole,

  • it would not survive the journey.

  • And there would be no way that the probe could transmit a signal outside once it had been sucked inside.

  • 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.

  • That is so strong that not even light can escape its grasp.

  • 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.

  • You may notice that when you see a photo of a spiral galaxy

  • such as the Milky Way in the center of the galaxy is a giant mass of light?

  • Which many people would think looks like a massive Sun, but this is not light coming from the black hole itself.

  • Remember that life cannot escape the heavy gravitational pull.

  • Instead the light we see comes from magnetic fields near a spinning black hole that propel electrons outward in a jet

  • Along the rotation axis the electrons produce bright radio waves.

  • Quasars are believed to produce their energy from massive black holes in the center of the galaxies in which the quasars are located.

  • But quasars are so bright they drown out the light from all the other stars in the same galaxy. You're probably asking well

  • What's a quasar a quasar is the short name for quasi stellar object and is a very highly energetic object?

  • Surrounding an actively feeding supermassive black hole in more basic terms the supermassive black hole in the middle of a galaxy feeds

  • intermittently as it feeds gas swirls around it at incredible speeds and

  • 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

  • They are essentially fueled by the black holes they orbit

  • some supermassive black hole giants release an extraordinarily

  • Large amount of light when they rip apart stars in devour matter and are likely the driving force behind these quasars

  • When material gets too close to a black hole it forms that bright hot accretion disk around the black hole

  • That accretion disk heats up to millions of degrees

  • Blasting out an enormous amount of radiation

  • The magnetic environment around the black hole forms twin Jets of material which flow out into space for millions of light years

  • This becomes what is called an active galactic nucleus

  • Or a GN the diet of known black holes consists mostly of gas and dust which fill the otherwise empty space throughout the universe

  • black holes can also consume material torn from nearby stars in fact the most massive black holes can swallow stars whole

  • Black holes can also grow by colliding and merging with other black holes

  • This growth process is what can and usually does reveal the presence of a black hole?

  • 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

  • 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

  • Galaxy is all out of food or space material to consume

  • It lies completely dormant for the time being a sleeping giant, so it doesn't have an active galactic nucleus

  • And so there is no quasar emitting light however

  • 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

  • Our supermassive black hole may roar back to life as a quasar as it begins to consume part of this new galaxy

  • Now it might sound like black holes are dangerous and that anything that even remotely comes close to a black hole

  • 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

  • You'd never get that object back, but black holes are actually remarkably bad at pulling material close to them

  • There are a couple of reasons for this one black holes aren't actually attractive to anything for any reason other than gravity

  • Much like our solar system is in a stable orbits around the Sun the vast

  • 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

  • The galaxy the second reason that black holes are bad at being astronomical vacuum cleaners is that they're really?

  • Really inefficient at getting material close enough to them to cross the event horizon and add to the mass of the black hole

  • 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

  • Growing their own size by consuming the star hole so despite their reputation

  • Black holes will not actually suck in objects from large distances a black hole can only capture objects that come very close to it

  • They're more like venus flytraps than cosmic vacuum cleaners for example imagine replacing the Sun by a black hole of the same mass

  • permanent darkness would fall on earth

  • But the planets would continue to revolve around the black hole at the same distance and speed as they do now

  • None of the planets would be sucked into the black hole our earth would be in danger

  • Only if it came within some 10 miles of the black hole

  • Much less than the actual distance of the Earth from the Sun which is a comforting 93 million miles away

  • So after knowing all of this do we have any idea, what is inside of a black hole?

  • Current theories predict that all the matter in a black

  • Hole is piled up in a single point at the center

  • 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

  • With the theory that describes the behavior of matter on the smallest scales called quantum mechanics

  • This unifying theory has already been given a name quantum gravity, but how it works is still unknown

  • This is one of the most important unsolved problems in physics

  • Studies of black holes may one day provide the key to unlock this mystery

  • Einstein's theory of general relativity allows unusual characteristics for black holes

  • For example the central singularity might form a bridge to another universe. This is similar to a so-called wormhole

  • Which is a mysterious solution of Einstein's equations that has no event horizon?

  • Bridges and wormholes might allow travel to other universes or even time travel, but without observational and experimental data

  • This is mostly speculation

  • We do not know whether bridges or wormholes exist in the universe or could even have formed in principle

  • By contrast black holes have been observed to exist and we understand how they form

  • What is actually inside of a black Cole is still a mystery?

  • So does a black hole live forever if there is nothing for a black hole to consume then no in

  • Fact a very surprising thing happens you might have heard of Stephen Hawking

  • He is a theoretical physicist in cosmologists, and is at the forefront on the study of black holes

  • He came up with a theoretical prediction that black holes emit radiation this of course is now known as Hawking radiation

  • Hawking radiation reduces the mass and energy of black holes and is therefore also known as black hole evaporation

  • Because of this black holes that do not gain mass through other means are expected to shrink and ultimately vanish

  • What it means is that if the black hole has nothing to eat it?

  • Eventually evaporates the energy and mass that the black hole pulled inside of itself

  • Evaporates back out into space in the form of radiation. It is almost as if a black

  • Hole is a universe recycling machine Stephen Hawking proved this in

  • 1974 by using the laws of quantum mechanics to study the region close to a black hole horizon

  • The quantum theory describes the behavior of matter on the smallest scales it predicts that tiny particles and light are

  • continuously created and destroyed on subatomic scales

  • Some of the light thus created actually has a very small chance of escaping before it is destroyed to an outsider

  • 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

  • This surprising new insight show that there is still much to learn about black holes

  • However, Hawking's glow is completely irrelevant for any of the black holes known to exist in the universe

  • For them the temperature of the glow is almost zero and the energy loss is negligible

  • The time needed for the black holes to lose much of their mass is

  • unimaginably long however if much smaller black holes ever existed in the universe

  • Then Hawking's findings would have been catastrophic a black

  • hole as massive as a cruise ship would disappear in a bright flash in less than a second as

  • You can see black holes are incredible and mysterious things perhaps one day

  • We will know exactly what lies inside of a black

  • Hole, maybe we will find out that they are gates to another dimension such as wormholes

  • Or maybe we will never know and just come to accept their existence as they are

What's inside a black hole?

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ブラックホールの中には何があるの? (What's Inside A Black Hole?)

  • 88 4
    Jerry Liu に公開 2021 年 01 月 14 日
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