BLACK HOLES
A black hole or black hole is a region of space-time caused by a large concentration of mass inside, with huge increase in density , resulting in an field gravity such that no particle or energy, such as light, can escape from that region.
The curvature of space-time or "gravity of a black hole" causes a singularity surrounded by a closed surface, called the event horizon . This is due to the large amount of energy the celestial object. The event horizon separates black hole region from the rest of the universe and is the boundary of space from which no particle can leave, including light . This curvature is studied by the general relativity , which predicted the existence of black holes and was its first indication. In the 70's , Hawking and Ellis [1] proved several important theorems on the occurrence and geometry of black holes. Previously, in 1963, Roy Kerr had shown that in a space-time four-dimensional black holes all had to have a quasi-spherical geometry determined by three parameters: its mass M, electric charge e and its total angular momentum L.
is believed that in the center of most galaxies , including the Milky Way there supermassive black holes. The existence of black holes is supported by astronomical observations, particularly through the X-ray emission by binary stars and active galaxies .
formation process
The origin of black holes is proposed by astrophysicist Stephen Hawking in his book Black Holes and the history of time. There he same comments about the process that gives rise to the formation of black holes.
This process begins subsequent to the death of a red giant (massive star), call it death to the total extinction of its energy. Subsequent to spend several billion years of the gravitational force star begins to exert force on itself, causing a mass concentrated in a small volume, thereby becoming a white dwarf . At this point the process can continue until the collapse of the star by the gravitational attraction car ends up turning to the white dwarf into a black hole. This process eventually assemble a force attraction so strong that light traps to at this time we can speak of infinite mass trapped without volume, which is the center of the black hole called the singularity . Over time this black hole could develop attractive forces sufficient to eat and even solar systems surrounding galaxies. Lately
has proven the existence of a black hole in the center of the galaxy where our solar system, Milky Way . History
black hole
The concept of a body so dense that even light could escape, was described in a paper submitted in 1783 the Royal Society for a English geologist named John Michell . At the time, Newton's theory of gravitation and the concept of escape velocity were well known. Michell computed that a body with a radio 500 times that of Sol and the same density would, on its surface escape velocity equal to that of light and be invisible. In 1796, the French mathematician Pierre-Simon Laplace explained in the first two editions of his book Exposition du Systeme du Monde the same idea though, to gain the idea that light was a wave massless in the nineteenth century was dropped in later editions.
In 1915 , Einstein developed general relativity and showed that the light was influenced by the gravitational interaction . A few months later, Karl Schwarzschild found a solution to the Einstein equations , where a heavy body would absorb the light. It is now known that the Schwarzschild radius is the radius of the event horizon of a black hole does not rotate, but this was not well understood at the time. Schwarzschild himself thought it was just a mathematical solution, not physical. In 1930, Subrahmanyan Chandrasekhar body showed that a critical mass (now known as the Chandrasekhar limit ) and does not emit radiation, would collapse under its own gravity because there was nothing to be known that he might hold ( for this mass the gravitational attraction would be greater than that provided by the Pauli exclusion principle ). However, Eddington opposed the idea that the star would reach a size zero, implying a naked singularity of matter, and should be something that will inevitably put a brake on collapse, line adopted by most scientists.
In 1939 , Robert Oppenheimer predicted that a massive star could suffer a gravitational collapse and, therefore, black holes could be formed in nature. This theory was not given much attention to the 60's because, after World War II, there was more interest in what was happening at the atomic scale.
In 1967 , Stephen Hawking and Roger Penrose proved that black holes are solutions to Einstein's equations and in some cases could not prevent a black hole be created from collapse. The black hole idea gained momentum with experimental and other scientific advances that led to the discovery of pulsars . Shortly thereafter, the term "black hole" was coined by John Wheeler . Classification
theoretical
Depending on their origin, can theoretically be at least three kinds of black holes:
primordial black holes
Those that were created early in the history of the Universe . Their masses can be varied and none has been observed. According
mass Supermassive black holes, with masses of several million solar masses. They are the heart of many galaxies. Form in the same process that gives rise to the spherical components of galaxies.
stellar-mass black holes . They form when a star mass greater than 2.5 solar masses becomes a supernova and implodes. Its core is concentrated in a very small volume every time is reduced more.
According to angular momentum A black hole without load angular momentum is a Schwarzschild black hole, while a rotating black hole (with angular momentum greater than 0), is called the Kerr black hole . Observable areas
Printing an artist from a black hole with a close companion star that orbits that exceeds its Roche limit . matter falls into an accretion disk shape, with some material that is ejected in highly collimated bipolar jets energy.
In the vicinity of a black hole tends to form an accretion disk . What makes up the matter with angular momentum, electric charge and mass, which is affected by the enormous gravitational pull of the same, leading inexorably to cross the event horizon and, therefore, increase it.
As for the light passing through the area of \u200b\u200bthe disc, is also affected, as provided by the Theory of Relativity . The effect is visible from Earth the momentary deviation occurs in stellar positions known, when the light beams passing from the same zone.
Until today it is impossible to describe what happens inside a black hole can only imagine, assume and observe their effects on matter and energy in the external areas and close to event horizon and ergosphere .
One of the most controversial effects imply the existence of a black hole is its apparent ability to decrease the entropy the Universe, which would violate the fundamentals of thermodynamics because all matter and energy electromagnetic passing through the event horizon, are associated with a level of entropy. Stephen Hawking proposes in his latest book that the only way that entropy would not increase the information of everything that crosses the event horizon continues to exist in some form. Another
implications of a supermassive black hole is the probability that it was capable of generating its complete collapse, becoming a naked singularity of matter.
Entropy black holes
According to Stephen Hawking on black holes violates the second law of thermodynamics , which gave rise to speculations about travel in space-time wormholes . The issue is being cause for review and now Hawking has recanted his initial theory and admitted that the entropy of matter remains inside a black hole (see external link). According to Hawking, despite the physical impossibility of escape from a black hole, they can end the call evaporating by Hawking radiation , an X-ray source escaping from the horizon event.
delivering Hawking's legacy in this area is of those who infrequently in physics, are described as beautiful. Delivery mathematical elements to understand that black holes have intrinsic gravitational entropy. This implies that gravity introduces an additional level of unpredictability over the quantum uncertainty. It appears, based on the current theoretical capacity of observation and experimental, as if nature took random decisions or, indeed, far from precise laws more generally.
The hypothesis that black holes contain an entropy and, moreover, it is finite, required to be consistent such holes emit thermal radiation, which at first seems unbelievable. The explanation is that the radiation escapes from the black hole, a region from which the outside observer knows only its mass, angular momentum and electric charge. That means they are equally likely all combinations or configurations of radiation particles that have energy, angular momentum and electric charge equal. There are many possibilities of bodies, if you want even the most exotic, which can be emitted by a black hole, but this corresponds to a small number of configurations. The largest number of configurations corresponds to an emission lot with a spectrum that is almost heat. Physical and
Jacob D. Bekenstein been linked to black holes and entropy with information theory.
black holes in the current physical
physical phenomena are explained by two theories that contradict each other, the quantum mechanics, which explains the nature of "very small", where chaos prevails and statistics, and general relativity , which explains the nature of "the very heavy" and that states that any time you can tell exactly where a body. Any of these theories are experimentally confirmed but, in trying to explain the nature of a black hole, it is necessary to discern whether to apply the quantum to be something very small or relativity to be as heavy. It is clear that until they have a more advanced physics not get really explain the nature of this phenomenon. Recent discoveries
In 1995 a team of researchers at UCLA led by Andrea Ghez computer simulation showed the possibility of the existence of supermassive black holes at the center of galaxies. After these calculations using the adaptive optics system verified something distorted light rays emitted from the center of our galaxy (the Milky Way ). Such deformation is due to an invisible black hole that has been called Sgr.A (or Sagittarius A ), while it is a mass 4.5 million times the Sun's supermassive black hole the center of our galaxy would be very active now as it has consumed much of the baryonic matter , located in the immediate area of \u200b\u200bits gravitational field and emits large amounts of radiation. In December 2008 a team of Max Planck Institute led by Reinhard Genzel confirms existence of such supermassive black hole at the center of the Milky Way calculándosele a mass of 4 million suns and considering a distance of 27,000 light years (about 254,000 million km from Earth). Meanwhile
astrophysics Feryal Özel likely explained some characteristics around a black hole: any, including space, which enters the tidal force caused by a black hole would be accelerated to extreme speeds as in a vortex and the whole time within the area of \u200b\u200battraction of a black hole would head into the black hole itself. This
is considered that, despite the destructive view that black holes have, they condense in the area around him serve in part to the formation of galaxies and the formation of new stars.
In June 2004 astronomers discovered a supermassive black hole, the Q0906 +6930 in the center of a galaxy located about 12,700 million light years . This observation indicated rapid creation of supermassive black holes in the young Universe.
The formation of micro black holes in particle accelerators has been informed [2] but not confirmed. So far, no candidate seen to be primordial black holes.
The biggest
In 2007 black hole was discovered, called IC 10 X-1 is in the constellation Cassiopeia near galaxy IC 10, a distance of 1, 8 million light years from Earth with a mass between 24 and 33 times that of our Sun, and is considered the largest to date. [3] Later in April 2008 the journal Nature published a study in University of Turku (Finland ) by a team of scientists led by Mauri Valtonen discovered a binary system, a blazar called OJ287 , such a system consists of a smaller black hole that orbits the larger, more mass would be 18,000 million times that of our Sun implies that for each rotation interval smaller the black hole ergosphere hits twice the largest generating a quasar .
The lowest possible Excluding black microholes almost siemper are ephemeral subatomic scales to be produced; macroscopically April 2008 the team coordinated by Nikolai Saposhnikov and Lev Titarchuk has identified the smallest black holes known so far, has been named 1650 J is located in the constellation Ara (or Altar ) of the Milky Way (same Galaxy which is part of the Earth). 1650 J has a mass equivalent to 3.8 soles and only 24 km diameter have been formed by the collapse of a star, such dimensions were provided by the equations of Einstein. They are considered almost the minimum dimensions that can have a black hole and a star to collapse and produce a lower mass phenomenon would become a star neutrons. It is considered that there may be many more black holes of similar dimensions.
plasma jets
In April 2008 Nature magazine published a study in the Boston University led by Alan Marscher explains jets of plasma start from collimated magnetic fields located close to the edge of black holes. In specific areas of such magnetic fields of plasma jets are aimed and accelerated to speeds close to C ( speed of light), such a process is comparable to the particle acceleration create a jet stream (jet stream ) in a reactor. When the jets of plasma that are caused by a black hole is observable from Earth that type of black hole falls into the category of blazar.
That a black hole emits "radiation seems a contradiction, however it is explained that all objects (assume a star) is trapped by the gravitational pull of a black hole before being completely" swallowed ", before going after event horizon is so hard pressed by the tidal forces black hole in the ergosphere of a small part of its subject matter shot out at speeds close to that of light (as when you squeeze an orange strongly Some of the material ejected out of the orange in the jets of juice, in the case of objects trapped by a black hole of its mass centrifugally shoots in the form of radiation outside the gravitational field of the singularity ).
Star Formation by the influx of black holes
New stars can form from elliptical discs around black holes, such discs are produced by old elliptical gas clouds previously broken by the same black holes, the stars produced by condensation or accretion of these discs appear to have elliptical orbits Highly Elliptical about supermassive black holes.
The curvature of space-time or "gravity of a black hole" causes a singularity surrounded by a closed surface, called the event horizon . This is due to the large amount of energy the celestial object. The event horizon separates black hole region from the rest of the universe and is the boundary of space from which no particle can leave, including light . This curvature is studied by the general relativity , which predicted the existence of black holes and was its first indication. In the 70's , Hawking and Ellis [1] proved several important theorems on the occurrence and geometry of black holes. Previously, in 1963, Roy Kerr had shown that in a space-time four-dimensional black holes all had to have a quasi-spherical geometry determined by three parameters: its mass M, electric charge e and its total angular momentum L.
is believed that in the center of most galaxies , including the Milky Way there supermassive black holes. The existence of black holes is supported by astronomical observations, particularly through the X-ray emission by binary stars and active galaxies .
formation process
The origin of black holes is proposed by astrophysicist Stephen Hawking in his book Black Holes and the history of time. There he same comments about the process that gives rise to the formation of black holes.
This process begins subsequent to the death of a red giant (massive star), call it death to the total extinction of its energy. Subsequent to spend several billion years of the gravitational force star begins to exert force on itself, causing a mass concentrated in a small volume, thereby becoming a white dwarf . At this point the process can continue until the collapse of the star by the gravitational attraction car ends up turning to the white dwarf into a black hole. This process eventually assemble a force attraction so strong that light traps to at this time we can speak of infinite mass trapped without volume, which is the center of the black hole called the singularity . Over time this black hole could develop attractive forces sufficient to eat and even solar systems surrounding galaxies. Lately
has proven the existence of a black hole in the center of the galaxy where our solar system, Milky Way . History
black hole
The concept of a body so dense that even light could escape, was described in a paper submitted in 1783 the Royal Society for a English geologist named John Michell . At the time, Newton's theory of gravitation and the concept of escape velocity were well known. Michell computed that a body with a radio 500 times that of Sol and the same density would, on its surface escape velocity equal to that of light and be invisible. In 1796, the French mathematician Pierre-Simon Laplace explained in the first two editions of his book Exposition du Systeme du Monde the same idea though, to gain the idea that light was a wave massless in the nineteenth century was dropped in later editions.
In 1915 , Einstein developed general relativity and showed that the light was influenced by the gravitational interaction . A few months later, Karl Schwarzschild found a solution to the Einstein equations , where a heavy body would absorb the light. It is now known that the Schwarzschild radius is the radius of the event horizon of a black hole does not rotate, but this was not well understood at the time. Schwarzschild himself thought it was just a mathematical solution, not physical. In 1930, Subrahmanyan Chandrasekhar body showed that a critical mass (now known as the Chandrasekhar limit ) and does not emit radiation, would collapse under its own gravity because there was nothing to be known that he might hold ( for this mass the gravitational attraction would be greater than that provided by the Pauli exclusion principle ). However, Eddington opposed the idea that the star would reach a size zero, implying a naked singularity of matter, and should be something that will inevitably put a brake on collapse, line adopted by most scientists.
In 1939 , Robert Oppenheimer predicted that a massive star could suffer a gravitational collapse and, therefore, black holes could be formed in nature. This theory was not given much attention to the 60's because, after World War II, there was more interest in what was happening at the atomic scale.
In 1967 , Stephen Hawking and Roger Penrose proved that black holes are solutions to Einstein's equations and in some cases could not prevent a black hole be created from collapse. The black hole idea gained momentum with experimental and other scientific advances that led to the discovery of pulsars . Shortly thereafter, the term "black hole" was coined by John Wheeler . Classification
theoretical
Depending on their origin, can theoretically be at least three kinds of black holes:
primordial black holes
Those that were created early in the history of the Universe . Their masses can be varied and none has been observed. According
mass Supermassive black holes, with masses of several million solar masses. They are the heart of many galaxies. Form in the same process that gives rise to the spherical components of galaxies.
stellar-mass black holes . They form when a star mass greater than 2.5 solar masses becomes a supernova and implodes. Its core is concentrated in a very small volume every time is reduced more.
According to angular momentum A black hole without load angular momentum is a Schwarzschild black hole, while a rotating black hole (with angular momentum greater than 0), is called the Kerr black hole . Observable areas
Printing an artist from a black hole with a close companion star that orbits that exceeds its Roche limit . matter falls into an accretion disk shape, with some material that is ejected in highly collimated bipolar jets energy.
In the vicinity of a black hole tends to form an accretion disk . What makes up the matter with angular momentum, electric charge and mass, which is affected by the enormous gravitational pull of the same, leading inexorably to cross the event horizon and, therefore, increase it.
As for the light passing through the area of \u200b\u200bthe disc, is also affected, as provided by the Theory of Relativity . The effect is visible from Earth the momentary deviation occurs in stellar positions known, when the light beams passing from the same zone.
Until today it is impossible to describe what happens inside a black hole can only imagine, assume and observe their effects on matter and energy in the external areas and close to event horizon and ergosphere .
One of the most controversial effects imply the existence of a black hole is its apparent ability to decrease the entropy the Universe, which would violate the fundamentals of thermodynamics because all matter and energy electromagnetic passing through the event horizon, are associated with a level of entropy. Stephen Hawking proposes in his latest book that the only way that entropy would not increase the information of everything that crosses the event horizon continues to exist in some form. Another
implications of a supermassive black hole is the probability that it was capable of generating its complete collapse, becoming a naked singularity of matter.
Entropy black holes
According to Stephen Hawking on black holes violates the second law of thermodynamics , which gave rise to speculations about travel in space-time wormholes . The issue is being cause for review and now Hawking has recanted his initial theory and admitted that the entropy of matter remains inside a black hole (see external link). According to Hawking, despite the physical impossibility of escape from a black hole, they can end the call evaporating by Hawking radiation , an X-ray source escaping from the horizon event.
delivering Hawking's legacy in this area is of those who infrequently in physics, are described as beautiful. Delivery mathematical elements to understand that black holes have intrinsic gravitational entropy. This implies that gravity introduces an additional level of unpredictability over the quantum uncertainty. It appears, based on the current theoretical capacity of observation and experimental, as if nature took random decisions or, indeed, far from precise laws more generally.
The hypothesis that black holes contain an entropy and, moreover, it is finite, required to be consistent such holes emit thermal radiation, which at first seems unbelievable. The explanation is that the radiation escapes from the black hole, a region from which the outside observer knows only its mass, angular momentum and electric charge. That means they are equally likely all combinations or configurations of radiation particles that have energy, angular momentum and electric charge equal. There are many possibilities of bodies, if you want even the most exotic, which can be emitted by a black hole, but this corresponds to a small number of configurations. The largest number of configurations corresponds to an emission lot with a spectrum that is almost heat. Physical and
Jacob D. Bekenstein been linked to black holes and entropy with information theory.
black holes in the current physical
physical phenomena are explained by two theories that contradict each other, the quantum mechanics, which explains the nature of "very small", where chaos prevails and statistics, and general relativity , which explains the nature of "the very heavy" and that states that any time you can tell exactly where a body. Any of these theories are experimentally confirmed but, in trying to explain the nature of a black hole, it is necessary to discern whether to apply the quantum to be something very small or relativity to be as heavy. It is clear that until they have a more advanced physics not get really explain the nature of this phenomenon. Recent discoveries
In 1995 a team of researchers at UCLA led by Andrea Ghez computer simulation showed the possibility of the existence of supermassive black holes at the center of galaxies. After these calculations using the adaptive optics system verified something distorted light rays emitted from the center of our galaxy (the Milky Way ). Such deformation is due to an invisible black hole that has been called Sgr.A (or Sagittarius A ), while it is a mass 4.5 million times the Sun's supermassive black hole the center of our galaxy would be very active now as it has consumed much of the baryonic matter , located in the immediate area of \u200b\u200bits gravitational field and emits large amounts of radiation. In December 2008 a team of Max Planck Institute led by Reinhard Genzel confirms existence of such supermassive black hole at the center of the Milky Way calculándosele a mass of 4 million suns and considering a distance of 27,000 light years (about 254,000 million km from Earth). Meanwhile
astrophysics Feryal Özel likely explained some characteristics around a black hole: any, including space, which enters the tidal force caused by a black hole would be accelerated to extreme speeds as in a vortex and the whole time within the area of \u200b\u200battraction of a black hole would head into the black hole itself. This
is considered that, despite the destructive view that black holes have, they condense in the area around him serve in part to the formation of galaxies and the formation of new stars.
In June 2004 astronomers discovered a supermassive black hole, the Q0906 +6930 in the center of a galaxy located about 12,700 million light years . This observation indicated rapid creation of supermassive black holes in the young Universe.
The formation of micro black holes in particle accelerators has been informed [2] but not confirmed. So far, no candidate seen to be primordial black holes.
The biggest
In 2007 black hole was discovered, called IC 10 X-1 is in the constellation Cassiopeia near galaxy IC 10, a distance of 1, 8 million light years from Earth with a mass between 24 and 33 times that of our Sun, and is considered the largest to date. [3] Later in April 2008 the journal Nature published a study in University of Turku (Finland ) by a team of scientists led by Mauri Valtonen discovered a binary system, a blazar called OJ287 , such a system consists of a smaller black hole that orbits the larger, more mass would be 18,000 million times that of our Sun implies that for each rotation interval smaller the black hole ergosphere hits twice the largest generating a quasar .
The lowest possible Excluding black microholes almost siemper are ephemeral subatomic scales to be produced; macroscopically April 2008 the team coordinated by Nikolai Saposhnikov and Lev Titarchuk has identified the smallest black holes known so far, has been named 1650 J is located in the constellation Ara (or Altar ) of the Milky Way (same Galaxy which is part of the Earth). 1650 J has a mass equivalent to 3.8 soles and only 24 km diameter have been formed by the collapse of a star, such dimensions were provided by the equations of Einstein. They are considered almost the minimum dimensions that can have a black hole and a star to collapse and produce a lower mass phenomenon would become a star neutrons. It is considered that there may be many more black holes of similar dimensions.
plasma jets
In April 2008 Nature magazine published a study in the Boston University led by Alan Marscher explains jets of plasma start from collimated magnetic fields located close to the edge of black holes. In specific areas of such magnetic fields of plasma jets are aimed and accelerated to speeds close to C ( speed of light), such a process is comparable to the particle acceleration create a jet stream (jet stream ) in a reactor. When the jets of plasma that are caused by a black hole is observable from Earth that type of black hole falls into the category of blazar.
That a black hole emits "radiation seems a contradiction, however it is explained that all objects (assume a star) is trapped by the gravitational pull of a black hole before being completely" swallowed ", before going after event horizon is so hard pressed by the tidal forces black hole in the ergosphere of a small part of its subject matter shot out at speeds close to that of light (as when you squeeze an orange strongly Some of the material ejected out of the orange in the jets of juice, in the case of objects trapped by a black hole of its mass centrifugally shoots in the form of radiation outside the gravitational field of the singularity ).
Star Formation by the influx of black holes
New stars can form from elliptical discs around black holes, such discs are produced by old elliptical gas clouds previously broken by the same black holes, the stars produced by condensation or accretion of these discs appear to have elliptical orbits Highly Elliptical about supermassive black holes.
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