Can Black Holes Evaporate?
Astrophysical black holes are objects so large, that have a gravity so high, that their escape velocity (about seven miles per second on Earth) exceeds the ultimate cosmic speed limit – the speed of light (186,000 miles per second). Because he can not travel faster than the speed of light, nothing (hardware and / or energy) once in a black hole never to leave – or if the logic seems to go tighter.
However, this is all according to classical physics. A physicist named Jacob Bekenstein came with the idea of ??applying quantum physics to the object (as suggested by his mentor John Wheeler – who coined the term “Black Hole”), and once that is done, well, here, these things suggest the entropy, and therefore the temperature and must therefore issue and because he can throw the goods. His ideas were pondered several times and finally agreed to expand and by astrophysicist / cosmologist Stephen Hawking famous. This thing that the black hole can spit now run under the name of Hawking radiation, or give credit where credit is due to the Bekenstein-Hawking radiation technique. However, it is usually just called Hawking radiation so I’ll stick with this convention.
Of course, if the black hole has a temperature, then they should follow the same laws as other objects with the thermodynamic temperature. A key point in thermodynamics is that energy exchange between the object at least partially determined by the temperature of an object other than the temperature of the object. The temperature of a cup of hot coffee stays hot longer, the ambient temperature around the hot cup of coffee. The temperature of a black hole should be compared with any object surrounding temperature when considering the fate of the black hole. So how to get the temperature of a black hole?
In retrospect, how this happens is clear (as are all great ideas when applied to the back).
There is no such thing as a perfect vacuum. This can be performed at a temperature of absolute zero where and when everything is 100% frozen. Unfortunately, such circumstances a violation of our most fundamental principles of quantum physics – the Heisenberg uncertainty principle – in which it is impossible to know both the momentum and position of anything with a 100% accuracy. If something is absolute zero, chilled and motionless, you will know both the momentum (which would be zero) and position (off), there is something with absolute precision.
Because there is always a minimum energy state anywhere in the universe (anything above absolute zero), and because energy and mass are equivalent (Einstein’s famous formula / equation) , then the energy state, false vacuum not quite absolute zero, a * vacuum energy, can produce a mass – a virtual particle. However, the particles come in a few matter-antimatter pairs, which are usually destroyed immediately and return to their former state of pure energy. BUT, and there is always a BUT – there are exceptions to the rule – that the normal state of affairs could not be defeated.
The vacuum energy, that can produce particle-antiparticle pairs, it is wherever his life has meaning. Part of the existence of an area called the event horizon **, which is a concept related to the notion that we call black holes. These objects all have a cosmic event horizon that surrounds them.
The event horizon surrounding the black hole is that vague area between the region (below the event horizon) whose rules of gravity on the speed of light, and the area (the above the event horizon) during which the exhaust velocity gravitational can not be sufficient to dominate this the speed of the speed of light. I say “vague” because it was not razor sharp, even if roughly.
The vacuum energy is part of the space around the event horizon, high, low and spot-on. Now, if the vacuum energy which produces a pair of virtual particles, each of which came into existence on the event horizon, one below the event horizon. Then, the particles will not be able to recombine and annihilate into pure energy. We will stay in the black hole. The other is above the event horizon, can be treated with “out of jail” card. And thus, slowly, very slowly, but still surely, this mass loss sink cosmic energy, and they evaporate.
Here’s an overview. Black holes can emit event horizon area, in a vast cosmic sink would be very cool, because it does not emit much, that it is primarily as a mass breakout of less photons. Assuming no one is going to indemnify, shrinking cosmic sink, and it warms a bit smaller (it’s the things that tends to shrink) and emit particles with small masses – such as neutrinos. When a cosmic sink is a small, very friendly, in a relative sense, and can not go out with a “bang”, can emit electrons or positrons that are much larger. When there is no more black holes, the vacuum energy still generates a random pair of virtual particles, but no more than the event horizon to separate pairs of virtual particles and therefore all back in the normal – and destroy the two returned to their state of vacuum energy. This is where the popular account of the end. End of story. The ultimate fate of black holes would evaporate through Hawking radiation, even if it does not take billions of years.
Unfortunately, the written texts forgot to mention that the emission of radiation (and other forms of property that are issued) is a two way street, not a one way street. A black hole can get the goods and products from. If withdrawals exceed deposits, the sink will always be a cosmic balance of “goods” is positive and therefore will not boil dry. Now this may be why Hawking radiation has not been observed. Small amount of radiation Hawking (outgoing) will be covered by an order of magnitude more, the amount of incoming radiation and other things that impact the black hole.
Remember this well universal (and their extreme gravity) for a while and concentrate on planet Earth. Even at night, you see lots of sun – a star. You see them because they emit photons – particles of electromagnetic energy of visible light, which is only a small part. In fact, you are only a fraction of photons detected visually because your visual detection equipment (eye) is not as effective. Optical telescopes take a more many of them, but they are still real. You also hit by the photons in the infrared, ultraviolet, the wavelength of the radio, X-ray photons, the photons of gamma rays, etc. While the Earth’s atmosphere protects us from some of the photons ( ultraviolet photons is much larger in numbers beyond our atmosphere than at the bottom), you can still be influenced by the multi-billions of them, the Earth is several orders of magnitude. Some of the photons can be reflected back into space, it does not add to a balanced energy / mass of the Earth. Overall, there are about a billion photons for every elementary particle with a mass, like electrons and neutrinos.
Also present on the Earth (and you) get hit by cosmic rays, neutrinos, and cosmic dust. Even if you’re lucky, Earth will be affected by meteors and space debris on the other, sometimes debris large enough to not only hit the surface, but cause considerable damage. Increase the mass of the Earth by one tonne per day, due to the Earth sweeps interplanetary dust and small rocks that intersect Earth’s orbit. Trillions of neutrinos that hit us so little that almost all of the past right, you and the entire planet and even if they have a small amount of mass, provided that our planet is concerned, they are of minor importance .
Now what about the black hole? Of course, these objects are not isolated from the cosmos and other objects inside. If you’re outside the event horizon, you “see” the photons (all wavelengths) because you will see stars and galaxies, etc. as you can on site. Neutrinos pass right through you will always be on their way to their fate after crossing the event horizon. Universe is full of intergalactic and interstellar atoms and molecules and dust, and certainly much more of a black hole can be a snack. Black holes will not sweep things like Earth, only more because it has more of gravity with which grab things with, and also because after being captured there is no way out for fish cosmic. Unlike Earth, everything that crosses the event horizon, the most striking cosmic sink, not to be returned (like photons). Neutrinos can pass through light years worth of solid lead without the “breathing” will be jailed when they tried to deceive the inner sanctum of a black hole there. And of course the atomic bomb, molecular, interstellar dust, chunks will also be imprisoned.
But we can imagine an ideal cosmos in which all the black hole has swallowed all existing radiation particles (photons), all atoms, molecules, dust and all great things – all the stars and planets, asteroids and comets, whatever mysterious “dark matter”. So, you just sink cosmos universal and cosmic vacuum energy (and perhaps a few bits and pieces from escaping, but so little to be inconsequential). Of course, there is an additional logical extensions. sink can swallow another cosmic cosmic sink. Black holes can merge to form larger black holes. The final product is that the cosmos consists of a black hole – Mother of all wells cosmic – and the vacuum energy! So you end up with a black hole is still standing with nothing to eat.
Okay, so now perhaps a new scenario is that it is the mother of all black holes evaporate by Hawking radiation. It could take billions of billions of years, but it does not evaporate. Because matter and energy can neither be created nor destroyed, after the hole Black Mother finally went “poof”, the universe is back where he started from – full of goods from photons to the particles they undergo chemical basis for the atomic and molecular form and the star-star and planet and possibly life – and the new black hole!
Maybe this is a new and improved version of the universe is cyclical / oscillating! – But then again, maybe not. There are obstacles that (but I’ll be you some time there!). That the “ideal cosmos” is just “what if” thought experiment.
First, it’s actually very, very unlikely that all black holes in the universe would never unite as long as the universe continues to expand. Because galaxies farther away from each other due to the expansion, a collection of black holes contained in each galaxy get more out of the other cluster of black holes in other galaxies. It’s like a passenger in a car to get more and more away from the passenger in another car when the car would each with different speeds and in different directions.
Now, the collection of all black holes in a galaxy can also merge into a single supermassive black hole galaxy. You have a galaxy containing billions of stars and not debris and particles now consists of one black hole – a single-occupant car. You have a pure galaxy black hole, or a galaxy-sized black hole.
People can end up with the universe consists only of galaxies with black holes pure, all spread out more and more infrequent.
But second, there is another obstacle. All the space that separates the pure galactic black holes from each other is not a perfect vacuum, regardless of the vacuum energy. All the stars shine and things could have been eaten in each galaxy, but the space between the planets, all of interstellar space, and all of intergalactic space, and not a pure vacuum. Still there ‘is ubiquitous, it is everywhere “cosmic background radiation (CMBR).
CMBR So what is it? If you have a heat stroke (like the Big Bang is thought to have), and all the energy of the heat expands and expands and then you wait until the temperature of the surface occupied by the energy goes down, the temperature continues to decrease as the volume which occupies a limited amount of energy increases. As energy grows, so cool it would be diluted, but it can never reach absolute zero temperature for the reasons already mentioned. And that’s exactly what we find on a universal scale. There is subtle microwave energy “sizzle” is the temperature a few degrees above absolute zero is really everywhere in the cosmos. This heat energy from the Big Bang diluted extremely hot – both have been long since the Big Bang (13.7 billion years the value of time) and energy is now spread throughout much of cosmic volume. The microwave “sizzling”, called the CMBR, it is estimated how it was discovered before. There is no doubt that it exists.
Since the CMBR is only photons of wavelength is very long, black holes can suck as photons of light photons CMBR easy. Elimination of RMC photons, already only a little on the theoretical minimum temperature – absolute zero – it would mean the universe will be cooler, which will remain, since the universe is expanding and therefore the electromagnetic energy available ( photons), which had cleared up. Combining these two effects and the universe is indeed a cool and cools.
However, it may not be possible for a collective black hole swallowing all the CMBR because there will come a point of diminishing returns. What happens when the temperature of black holes at the temperature of the universe in general – the CMBR? The answer is the thermal equilibrium such as when your cup of hot coffee to cool to room temperature. Put into a black hole is equal to the output of the Hawking radiation CMBR. For each photon is emitted by Hawking radiation, a CMBR photons will be sucked in. What does this mean? This means that a black hole can not evaporate.
How about a very small (micro) black holes are relatively “hot”? Could they go “poof” before thermal equilibrium is reached? The contents of the black hole evaporation in the surrounding cosmos before they can be the same as the ambient temperature? An analogy could be like a drop of hot water can evaporate into the atmosphere to cool before the drop of liquid water can reach temperatures of the environment.
Nevertheless, I still think in terms of the present universe and the radiation dominated, the entry will always be greater than the output.
Of course, if you can take the Black Hole, insulate and protect the entire cosmos and everything in it, so all you have is a black hole and internal energy (including the vacuum energy is ubiquitous in the it). A black hole is isolated in an equivalent put into the environment of absolute zero temperature. If this happens, it will be over because there can not enter, and therefore that the black hole and then spread gradually disappeared and finally went “poof”. BUT, and there is always a BUT, I can not imagine a scenario in which the black hole could theoretically exist in such isolation. Thus, Professor Hawking is very true – in theory. In practice, here and now, the input is greater than the output of Hawking radiation, and even the balance of a future unimaginable there is much to be formed in which the same input to output.
* If it helps to understand the concept of vacuum energy, an analogy here. Think of the atmosphere but invisible energetic than the vacuum energy. Part of the atmosphere is composed of invisible water vapor. But, suddenly, and for a specific reason for the mysterious ancestors, part of the atmosphere undergo a phase change into something you see, in something solid – like a particle. You get a mist / fog (cloud), drops of rain, snow, sleet, hail, etc. Then, just as mysteriously, the other bit dense eventually undergo a phase change (evaporation to replace the extermination) back to invisible water vapor in the atmosphere are also invisible. And if you have a vacuum energy which produces invisible particle-antiparticle pair annihilate back into the vacuum energy.
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