Black Holes

somewhere in our galaxy at some point in the future Earth's spaceship will encounter the most dangerous object in the universe this is an object that is not made of ordinary matter it is not made for antimatter it does not matter that it has matter at all it is made from a pure warp of space and time nothing comes out of things it only goes into them it's that unidirectional nature that probably bothers the people the most that really disturbs us the most, in fact, it disturbs many scientists Matt Reich was quite surprising when The Astronomers discovered that there were very good reasons to suspect that the universe should be full of these extraordinary objects.

At some point in the future, a spacecraft from Earth will encounter an extraordinary universe full of

black

holes

. We have all heard about

black

holes

. Nobody has really seen. them, the spaceship of our dreams has not reached a solid object but the edge of a region of space where gravity has gone crazy waiting below like a black hole in space, this is where a powerful star has died and left a bottomless pit from which there is no escape welcome to the edge of the universe and the end of space and time phil charles not only dreams of black holes, but hunts them for a living, he has found the strongest evidence yet of a black hole lurking in our own galactic backyard looking for these things is the most wonderful way to push the frontiers of modern physics, the most exciting thing modern scientists can do during the day Phil Charles lectures on astrophysical theory at the University of Oxford, overnight, at the forefront of the search for astrophysical facts to be a successful black hole hunter you must have easy access to the largest ground-based telescopes we have to travel around the world from Palmer and Hawaii in the northern hemisphere to South Africa Chile and Australia and the southern hemisphere around the world Phil Charles and his Our fellow astronomers draw on the world's most sophisticated astronomical arsenal to explore the depths of space in search of these mysterious objects, from X-ray satellites and the Telescope Hubble Space in orbit to the best radio telescopes and optical telescopes on the ground.

Today's destination is La Palma, in the Canary Islands. Nepal is definitely one of my favorite places. I have been studying black holes on La Palma for more than seven years. The very nature of black holes makes them, by definition, lucid quarries if they cannot be seen and the material falls into its only place. In the 1990s, when mainstream science reached a consensus that black holes could really exist, theory tells us that deep inside black holes, everything we know about the universe will come to an end, the real universe, but the math is unambiguous when a massive star dies.

He will have no choice but to form a black for astronomers like Phil Charles. Black holes are still the big game of the universe, but how do you capture a tiny, invisible nothingness that may be hundreds of thousands of light-years away across the noisy ocean of space with more stars in the sky than all the world? grains of sand on all the beaches in the world, how do you look for that dark star that swallows well instead of shining like a lighthouse? Astronomers should not look for black holes themselves, but for the effects they generate in the space around them.

For them, Phil Charles looks for visible stars that black holes could have trapped in orbit, but even they can be difficult to find. When you look for a needle in a haystack, we need the needle to scream that they were here and that, in fact, we do it. In the late 1980s, the Japanese launched an X-ray satellite called Ginga that had what we call an all-sky monitor to detect X-rays from anywhere in the sky. It is the X-rays that alert us to the presence of this needle. the needle in the haystack they were looking for while sweeping the skies in 1989 the Ginga satellite reported a mysterious burst of X-rays in our own galactic neighborhood the source of the radiation was an invisible object three thousand light years away around which a faint the star appeared to be spinning the star had the catalog name V 404 Sydney was simply the full star Charles has been searching for Phil Charles the meddling weapon in the search for black holes is the enormous William Herschel telescope perched on the edge of a volcano extinct two and a half kilometers above the Atlantic Ocean, well, actually the loaded grids said they were working for the last seven years.

Charles has pointed the telescope at the star V 404 trying to determine what type of highly compact object must be orbiting the star the most. The likely candidate is a stellar-mass black hole, the most common type according to theory. Such a black hole would have to weigh ten times more than a star like our Sun, but would only be about the diameter of the center of London. Less common is a second type of black hole. Supermassive hole heavyweights are believed to lurk at the heart of galaxies, but to understand any blackness, you must start with gravity, for within this darkness gravity is in complete control.

Our modern quest to understand gravity and, ultimately, black holes was born in this room on Christmas Day 1642. But it was a shaky start. The great Isaac Newton was premature and barely survived his first day of life, showing little promise as farmer young Isaac Newton was sent to Cambridge University as an academic who would formulate laws of physics that still form the basis of modern science fate played its part in 1665 the plague swept through England Cambridge was closed to help contain the spread of contagion Anoop, who was forced to flee, sought refuge at Woolsthorpe mansion for the next 18 months here he would discover the mathematics of calculus to formulate laws for the movement of planets and unravel the spectral nature of light and one day a The falling apple interrupted his thoughts and led him to reflect on gravity itself.

Newton was the first person to give us a really detailed mathematical understanding. of one of the basic forces of nature and of course it was the first great triumph of mathematical physics, it told us that the force that keeps us here on earth and that allows an apple to fall is the same force that keeps the moon instead. its orbit around the Earth and causes the planets to move in its courses Nutan reasons that all matter in the universe has gravity, which is a force that extends from one body to another and attracts everything in words, the more mass it has. an object, the more gravity it has.

This is stronger inward, as the first person to combine this notion of the inward pull of gravity with the knowledge that the speed of light was finite was John Mitchell as rector of Thornhill church in Yorkshire and one of the great forgotten scientists of the 18th century. Mitchell adopted Newton's view of gravity to its ultimate dark conclusion. Mitchell's great leap was to imagine a ray of light leaving a star in the same way we think today of a rocket leaving the planet to escape the attraction entirely. gravity of the Earth and travel to space. A rocket needs to propel itself upward at 11 kilometers per second faster than gravity tries to pull it down Mitchell didn't know anything about rockets to the Moon, but he did know that, in theory, a massive star could have so much gravity that it would pull into its clutches. even light rays traveling at 300,000 kilometers per second John Mitchell discovered that if you had a body that weighed a hundred million times as much, the light from the Sun couldn't even escape from it and then went on to say that for that reason perhaps the most The universe could be invisible to us.

Mitchell had explained how gravity could turn a star black, but not how it could turn it into a whole. A complete understanding of the life and death of stars awaited the nuclear age. Every star we see in the heavens has a giant star. The nuclear reaction that is triggered in its core is what makes a star like our Sun shine so hot and bright. Only the nuclear reaction keeps gravity at bay. The energy that pushes outward prevents the Sun from attracting itself more and more. It is smaller and denser. It's a precarious balance that gravity will create.

In the end we always win when the Sun runs out of nuclear fuel, its own gravity will crush it into a small ball the size of the Earth but a hundred thousand times denser, but our Sun has very little mass and therefore very little gravity to become a black hole, on the other hand, astronomers call such a weak ember a white dwarf, but when a giant star goes out, an explosion occurs while we see the explosion outward as a supernova, this masks the implosion that occurs within the call has been given such extreme severity. that all atoms have been compressed into a ball of super-dense subatomic particles called neutrons.

It has become a neutron star barely 20 kilometers in diameter. We know that ordinary stars like the Sun will become white doors. We know that there are neutron stars. which are a little bit heavier and the question is what lies beyond that and we think that black hole theory suggests that when a neutron star is more than three times heavier than our Sun, not even the neutrons can resist gravity, collapse occurs. irrevocable mass density becomes so great at the center that gravity overwhelms space itself distorting it so horribly but and joining it begins to tear itself away from the outer universe its darkness forms in the heart of the collapsing star and moves relentlessly towards out as the the star's brightness is absorbed as the star dies, a black hole is born Mask of computers, find out what you can about it, we judge this is a bit about black holes, they are stars that have collapsed onto The forces within a black Sun are inconceivable, they are capable of anything, they can bend space, even time, turning both upside down.

How a black hole can manifest itself so powerfully in the vacuum of space is something that weighs heavily on Professor Stephen Hawking, born exactly 300 years later. Isaac Newton Hawking now occupies Newton's old job at the University of Cambridge Hawking's mind wanders freely not in Newton's universe but in Albert Einstein's universe towards the Earth but ruling the Earth towards the Sun brilliant idea that gravity could be caused by the curvature of space and time Einstein realized that nothing can exist at a point in space without also existing at a particular moment. Space and time seemed to be interwoven to form the flexible four-dimensional fabric of the universe, the so-called space-time.

Space-time is almost impossible to contemplate because our entire sensory existence is limited to the three dimensions of everyday experience. The easiest way for us to enter Stein's universe is to imagine that space and time are like a sheet of rubber. This curvature is Einstein's concept of gravity. The more mass a star or planet has. has the more sharply it bends space-time around it and therefore the more gravity it has, throw something extremely heavy like a collapsing star onto the sheet and you soon end up with a universe full of holes. Look at it Coney, oops as an acid cools and contracts that will slow down the space-time around it eventually when it contracts to a certain critical size that will literally create a black hole in space-time things can fall into a black hole but nothing can be cut so much I don't know about astrophysics I wish I had read that book by that guy in a wheelchair the most terrifying concept in astrophysics hides at the bottom of a black hole the singularity everything that has ever fallen into the hole is destroyed In the singularity crushed into a point of infinite density and infinite smallness even space and time disappear all that remains in the outer universe is a perfect sphere of absolute darkness the gravitational ghost of the star that died this fear is called the horizon of events and marks the edge of the abyss this event The horizon is not made of matter, in a sense it is almost not even made of a warp of space-time, it is just a location, it is that unique location where gravity becomes so strong and It is so deep inside that nothing can escape, while the event horizon may only be a few kilometers in diameter the immense gravity of the singularity will have sucked a hole inside that is impossible to measure, at the center is the so-called singularity which is a place where according to Einstein's theory everything becomes infinite where if we do calculations, so to speak, smoke comes out of the computer and something goes wrong and what that means is that deep inside the black hole we have black holes, we have asign that we need some fundamentally new physics to understand what's going on, slit astronomer girl.

Phil Charles believes he has proven that such intangible objects are found in the real universe. The telltale sign was the sudden burst of unexplained X-rays that alerted Phil to V 404, a faint star trapped in orbit around an invisible compact object. These are signatures. from a star not unlike the Sun and represents more than 80% of the light here that we can track and use the velocities we measure to determine the mass of the object we cannot see. An excellent analogy is that of a large and strong man on a very small and light woman as they balance around each other, the man barely moves and the woman, despite the balance of her weight, moves much more.

Calculations show that V 404 orbits a heavy, mysterious companion once every six and a half days to reach speeds like these, the companion must be very heavy, in fact the mass we measure through this process is 12 solar masses, twelve times the mass of the Sun, meaning it is substantially heavier than what we think is the largest mass of a neutron star we know of. We're virtually certain it's a black hole: the black hole has embraced V 404 in a deadly dance, ripping gas from the hapless star and feeding it into a large disk of cannibalized matter as this material spirals toward the hole, heating up. and sends one last desperate x. -Ray signal to the outside world Nearly a dozen similar objects have had their presence betrayed to astronomers in the same way by X-ray signals.

One of the first was Cygnus x1. I made a bet with Stephen Hawking on whether Cygnus x1 was a private individual. The object of which the X-rays were visible was a black hole. Stephen Hawking told me that it was not because he wanted an insurance policy. He had done a lot of work on black holes and it would all have been in vain if it had turned out that black holes didn't exist, but at least he would have done it. He had had the consolation of winning with a pet when Hawking and Thorne made the bet in 1974, the evidence was slim, but as the years went by and the evidence mounted, Hawking felt it was safe to concede the bet in 1990.

Stephen Hawking was visiting Los Angeles. Angeles, he barged into my office and gave the thumbs up to this bet. His wife argued. This handwritten bet has come to symbolize the first real recognition by the scientific establishment that black holes really exist. All the ready robotic spaceships have explored the planets that we will one day be able to send to. An intelligent probe to a black hole in the depths of space beyond our mothership travels fast enough to insert itself into a safe orbit around the hole. A different fate awaits the probe. As I approach the black hole, I will begin to feeling a gravitational pull on myself is a different kind of gravitational pull or pull and you're used to it, normally you think you're just being pulled down as I sit here in this chair, my head is further from the center of the earth than my chest, so my head is pulling less hard than my chest, so there is actually a difference in the pull. my head is being pulled less tightly than my chest.

Gravity is actually stretching me slightly. Did you get close to a black hole? that difference in pull becomes large or larger. as you get closer to the center the gravity will become more extreme, you will be squeezed and distorted spaghettification is the name something that can be used for this experience spaghettification is an experience nothing can survive the fragments fall towards the darkness of the house in which you or I fall the black hole will stretch and our bodies will be too mutilated before we even reach the horizon it's not good, we can't free ourselves he is accelerating something stranger happens long before the event horizon is crossed not only space is The closer the probe gets to the event horizon, the harder the light coming out of it struggles to escape.

The mothership sees the probes slow down until they appear to stop. Time doesn't change for the probe because gravity is stretching its entire existence, but from the mothership's perspective. the probe has been frozen in time, destroyed in an instant and floats for eternity depending on your point of view. However, if you are inside that spaceship looking at me, you can wave at me, you can see me, you can think I can see you, but I can't and you enter the event horizon you can still see outside you can still see me outside until the point where you die You can still see me outside You'll have to jump He's the king What happened?

Well, we ran into a bit of a problem when the universe collapsed in on itself. We really don't know exactly what would happen deep inside a black hole if you fell directly into it. It could be that something even stranger happens to space under these conditions. like what turns out to be any part of the universe, and in fact some people have speculated that it may generally be possible to avoid the complete singularity and emerge somewhere else; Some say that if you pass through a rotating black hole you end up in a new universe. new dimension we have entered.

I remember a movie where at the end the spaceship enters the black hole and comes out the other side to another universe, that doesn't happen, it just doesn't happen at all, the fundamental laws. Physics scientists say that at the center of the black hole there is a singularity, a region where a base and time or infinitely warped, a region where when matter flows into it, the matter is destroyed, but it has to be like that, this is the worst place so far, speculation. That tamed black holes can provide a way to cheat the laws of physics has become a hallmark of science fiction.

Physicist Igor Novikov likes to speculate about what would happen if two black holes join together to form a wormhole. We can imagine a wormhole as two holes. and a kind of tunnel between them, but this tunnel is not in our space and is in some kind of hyperspace outside our dimensions. The first employee to make such a wormhole would have to design space-time, first fold it until it begins to form a black hole but not so much that a singularity is born, then join the bottom of this gravity tunnel to the bottom of a second tunnel to make two holes connected by a continuous tube through hyperspace.

The second step would be to move a hole to wherever you want it to be. Did you want to travel? One of them may be near our Earth in our galaxy, but this tunnel may be extremely short, say a few meters. The tunnel would also be very fragile and prone to collapsing as soon as a traveler attempted to pass through it. But if we could develop the technology to master the fierce forces at work, we would have opened an interstellar shortcut. He can travel from one galaxy to another galaxy for only a few seconds. We are a black hole.

It is a one-way street. with a singularity dead end, a wormhole, a highway to the stars. I have to say that they are driven by sort of romantic science fiction ideas, which is fine, I mean, a lot of science has led that way and you and you make good things. There's nothing against that directly, it's just that it seems to me that the scientific evidence is that this is not going to happen, it's just not possible. Roger Penrose of the University of Oxford takes the mathematics of black holes in a different direction. He has formulated a way to extract enormous amounts of energy from the way black holes spin while sending enormous amounts of garbage into oblivion.

In the real universe, most black holes should spin because the stars that form them would have been spinning as they collapsed their massive gravity spinning the fabric of space around them. them as water around a world The process of extracting energy from the Penh roses would require the construction of a power plant at a safe distance around the rotating hole. You could imagine shooting many particles or bodies in the vicinity of the rotating hole in the right direction. The forces of spaghettification. will tear these particles apart, a particle carries negative energy to the hole and that means the companion has more energy than the one that fell into it, so you can extract energy from a black hole through this process, the particles could be any junk that you can imagine.

I never wanted to see again half would disappear into the hole the other half would be blasted outward with a slingshot of gravitational energy that could be used to drive a turbine the source of that energy affects the slowing of the black hole's rotation because as these Particles keep falling into the hole, gradually slowing it down, but since there is normally a huge amount of rotational energy in a rotating black hole, this would be an extraordinarily efficient way to extract energy, but there is still a long way to go before that observational science reaches the wildest. speculations about the black hole theory another country another telescope the search is carried out Charles to Australia Australia has access to the southern hemisphere of the sky and there we can see the Magellanic Clouds, then the Large Magellanic Cloud is our closest neighbor galaxy and There are about half a dozen very interesting compact objects that we want to study from here we need to get maybe 20 or 30 so you can really see the population of black holes that we are looking at if they all have similar mites if there is mass distribution they all come from the same type of original stars, we could begin to solve it once we have enough time while Phil Charles turns his gaze to the stars of our neighboring galaxy, other astronomers are investigating more distant galaxies, here they are finding objects of astonishing dimensions.

The intensity was formed not from the death of a single star but from the collapse of enough matter to form millions of objects like what astronomers now believe are supermassive black holes. Since radio telescopes began spying on the skies, the strongest and most disconcerting signals have come from the hearts of human beings. distant galaxies, astronomers now suspect that these radio signals are generated by central supermassive black holes. Powerful jets of energized particles are launched into space from an invisible engine that propels these so-called radio galaxies like great wheels across the sky. Nameless stars are torn apart by immense Gravity to feed central disks of white-hot matter that shines a hundred times brighter than an entire galaxy of stars like our Milky Way is the hidden central object that powers everything, as small as our solar system, but we are enough matter to produce millions or even billions of stars have undergone a titanic gravitational collapse tonight we are looking at the radio galaxy m87 m87 is a nearby giant galaxy that is very unusual in that it has a large, powerful jet coming out of it.

The m87 jet is like a huge death ray of charge particles moving near the speed of light and with a length of six thousand light years, the jet is a signature of the way the black hole spins matter. and the space around it. Astronomers use the speed of the spinning matter to calculate the mass of the black hole. We're talking about a black hole that has a billion solar masses or more, so it's much larger than anything we're used to seeing in our own galaxy, but it's pretty typical of what we think many radio galaxies have in their core.

Astronomers suspect that radio galaxies are those galaxies that have a lot of black hole matter left to eat. If a galaxy seems calm, it's probably because the black hole has run out of food. If we look at the center of almost any galaxy there should be lurking a dark mass of millions. of solar masses at least, which may be the remnant of some past activity in that galaxy and in recent years there has been growing evidence that these dark masses really exist, but seeing them is still out of reach, even the latest images Hubble's high-resolution images can show only the bright central disk, the jets of energized particles, but not the black spot in the middle, we will never be able to appreciate the full majesty of a supermassive black hole from Earth, it is time for our spacecraft take another trip if one were to take a The trip begins on the outer part of a galaxy and moves in the sea, blows very hot gas that fills the galaxy that is being heated by some mysterious and powerful central source and finds gas orbiting in the disk spinning at almost the speed of light and getting very hot and setting. so hot that it radiates not only visible light but very energetic radiation such as X-rays.

It is one of the great cosmological contradictions that the larger theblack hole, the weaker the gravitational forces near the event horizon. This time there is no spaghetti as we approach the event horizon the intense gravitational curvature tears the light from the universe to a bright point directly above us we have reached the point of no return now we are inside the black hole but where is the singularity if you're falling into a black hole and the singularity you knew from your calculations that the singularity was out there and you're heading towards it you look at it you don't see it it's like a singularity that you're heading towards in the future and you don't actually see it the singularity It is where science ends and speculation begins.

Space and time have ceased to exist, replaced by a chaotic and boiling mass that we can call quantum foam. In this strange conjecture, all the mass and energy that has ever fallen within the horizon of space has disappeared. events this is where Einstein's laws fail this is where the laws of quantum mechanics fail this is where the secrets of the universe are hidden the singularity is an object in the nucleus of a black hole that is not governed by the ordinary laws of physics with which we are familiar, but by the laws of quantum gravity that we are only beginning to glimpse and understand, if the probe were strong enough, it would fall towards the singularity for perhaps an hour until it blindly found its future at the end of space and time, then you would experience the final crack in the center. learning in your final moments that perhaps the new physics will prevail in those moments, but you will not be able to send any signal to the outer world of the inner region, what really happens to it in the end is as unknown as what happened before the Big Bang.

It's the other end of that story, we hope to find singularities in the Big Bang, well of course that was the first one where we worried about black holes and in the Big Crunch thing, one is the virial temperature that they can have the electrons. Pretty cool, but what we have, of course, are two tornadoes orbiting inside a larger tornado and approaching each other and colliding and merging. The world's leading cosmological minds can now come together to speak with facts and figures about what not long ago were dismissed as flights of fancy showing of course it is observational it cannot be it seems that our understanding of the nature of the universe is accelerating day by day.

Today these are the facts it seems that most nearby galaxies and perhaps therefore most galaxies host a central black hole our galaxy would seem quite disadvantaged if it did not have one too, the evidence that has arrived only in the last few months ago make this a compelling case. Astronomers are virtually certain that hidden behind the dust at the center of our own Milky Way galaxy is a black hole weighing three million times the mass of the Sun, even just five years ago people thought we could get away with it. ours without having to have black holes in our own galaxy.

We could explain almost everything we see using neutron stars. No theorist now believes that When it comes to ordinary neutron stars and more, there are things out there that have to be compact and have to be explained and I think that is an extremely exciting prospect. Everyone has trouble accepting the black holes locked inside these prisons of light. secrets of the universe where it came from and where it isWe may never answer these questions, but for once we know where the answers are.