The simplest type of black hole in which the core does not rotate and is just a singularity and an event horizon, after the German physicist Carl Schwarzschild, is known as Schwarzschild Black Hole, which leads a very early principle behind the black hole. In 1910, with Albert Einstein. In 1958, David Finkelstein published a paper, which was based on the work of Einstein and Schwarzschild, in which the idea of "one-way membrane" was described, which created a renewed interest in black hole theory ( However this phrase was not prepared until a lecture by John Wheeler. In 1967).

In 1963, New Jodender Roy Kerr discovered a solution for field equations of Einstein's general relativity, in which a spinning object was described, and suggested that whatever fell would ultimately fit into a spinning black hole. It revolves because the star that formed it revolves, and it is now thought that it is actually possible to be the most common form in nature. Due to a rotating black hole moving around from outside its equator (faster spin, more bulge).

In the mid-1960s, young English mathematician Roger Penrose devoted himself to the study of black holes, and in 1965, he proved to be an important theorem, which showed that the gravitational gravitation of a large dying star was in a singularity Should be transformed, where space-time cannot be continued and classical general relativity is broken. Penrose and Wheeler proved that any non-rotating star, although its initial shape and complex of the internal structure, will be eliminated after the fall of gravity in the form of a fully spherical black hole, whose size is completely Depends on its mass.

In the late 1960s, Penrose collaborated with his Cambridge friend and colleague, Stephen Hawking, to further investigate this subject. He applied a new, complex mathematical model derived from Einstein's theory of general relativity, which in 1970 gave Hawking the proof of the first of many singular theorems. Such theorems provided a set of circumstances enough for the existence of a gravitational specificity in space-time, and showed that, away from mathematical curiosities, which only appear in special cases, the singularity is actually a great deal of general relativity The general feature is:

Although it can be a very complex, strange and perhaps counter-intuitive object, a black hole can essentially be described by three quantities: how much mass is gone in it, how fast it is moving (Its angular momentum) and its electrical charge This is known as "no hair theorem" after John Wheeler's comment, "black holes do not have hair", by which they meant that any other information about the matter that formed a black hole ( For which "hair" is one metaphor) is permanently inaccessible to external observers within its event horizon, and all are irrelevant.

In the early 1970s, Brandon Carter and Stephen Hawking mathematically proved a no-hair theorem that the shape and size of a rotating black hole would depend only on the rate of mass and rotation, not on the nature of the body. Make it up He proposed four laws of black hole mechanics, related to temperature by gravity, the entropy of the field, and gravity of the surface.

In 1974, Hawking jolted the world of physics, showing that black holes should actually create and emit sub-atomic particles, which are today known as Hawking radiation until they end their energy Do not do and are completely evaporated. According to this principle, black holes are not completely black, nor do they remain forever.

Hawking showed how strong gravitational field around a black hole could affect the production of particles and antioxidants, as per quantum theory, that is happening all the time in the empty space. If the particles are made just outside of the event horizon of the black hole, then it is possible that the positive member of the pair (say, an electron) can survive - while the heat from the black hole is observed as the thermal radiation - while Negative particles (say, a position, with its negative energy and negative mass) may fall back into black holes, and thus black holes will gradually lose the mass. This was probably one of the first examples of the theory that synthesized, at least to some degree, quantum mechanics and general relativity.

However, there is a so-called "information paradox" or "Hawking paradox", from which physical information (which means the distinctive identity and attributes of particles entering a black hole) is completely lost for the universe. In violation of accepted laws of physics (sometimes referred to as "the law of protection of information"). Hawking strongly opposed this contradiction against Leoard Susskind and the arguments of others for nearly thirty years, until he withdrew his claim in 2004, Second suffered defeat, "black hole" War "was known. The latest line of Hawking's logic is that the information is actually preserved, though perhaps not in our observable universe, but in the multiverse as a whole, in other parallel universes.

Unfortunately, the proposed solution of Suskind is even more difficult, and it is almost impossible to think or interpret in an understandable way. He suggests that, as an object falls into a black hole, a copy of the information that makes it is like a frozen and blotch in two dimensions around the edge of the black hole. In addition, Szckind believes that a similar process is accomplished in the universe, which gives rise to this dangerous idea that what we perceive as a three-dimensional reality is actually a holographic representation of "real" reality. There is something that is actually rooted in the two dimensions around the edge of the universe.

It is also theoretically possible that in the early moments after the "primorial" or "mini" black hole after the Big Bang, it could have been born in situations, possibly in large numbers. Such a small black hole has never been seen, though - in fact, it would be very difficult to spot them - and they are quite speculative. It is probable that all but the biggest of them have already been evaporated since they leak to Hawking radiation. According to the theory of Hawking, the amount of lost mass is more for small black holes, and therefore quantum-shaped black holes develop on a very short time scale. But it is hoped that such mini black holes can be experimentally created in extreme conditions of the Large Hadron Collider in CERN, which will lend much-needed evidence to some of the current theoretical predictions of superstring theory, among other things. Gravity

HAWKING RADIATION & BLACK HOLE THEORY Reviewed by Know It All on March 05, 2019 Rating:

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