Black Holes
Stars - are in constant development. Gradually, the thermonuclear fuel is burned in them, and star of "aging". The greater the mass of the star, the shorter its life, the faster it becomes a red giant and then could turn into a white dwarf, very slow to cool down, or under contract to the gravitational field of the nuclear density, becoming a neutron star, or explode as a supernova Or become a star, invisible under the name "black hole".
From Einstein's relativity theory the existence of these unusual objects to be the inevitable. Gravitational forces associated with the physical properties of space itself. It turns out that any body not just exists in space itself, but changes around its geometry.
In everyday life we do not notice a curved space, because we have to deal with relatively small masses, but in outer space objects can have an enormous weight - hence the powerful gravitational field that bends space, just as a massive ball bends taut fabric.
On such a surface some light items will slide in the direction of the ball, as though attracted to him. Powerful gravitational field of a massive star so much squeezes her stuff, which not only matter, but even the radio waves can not escape from the star, and it ceases to be visible. Everything - the substance of any kind of radiation - will be like to fall into an invisible hole.
In a black hole can become massive stars (larger than our sun in a few times!) For their catastrophic compression - the collapse. Star collapsar, it is a black hole, picks up radiation from the outside, but she does not let out any radiation. Time and space in the collapsar get amazing properties: They shrink to one point, in fact, cease to exist. To an observer, would be the "edge" of a black hole, there is no distance around, there is no past, no present or future.
Group of Italian scientists in the lab received the radiation of a black hole, which was first predicted by physicist Stephen Hawking in 1974.
According to existing ideas, the universe is filled permanently nascent pairs of particles and antiparticles. Shortly after birth, they annihilate each other, and the balance is not disturbed. However, close to black holes, the situation may change.
Black holes arising from gravitational collapse of massive stars have such strong gravity that it can not be overcome, not exceeding the speed of light. No facilities or radiation can not escape from overseas impact of the black hole, which was called the event horizon.
Hawking has predicted that the fate of the particles produced near the event horizon, can be very different - one of the pair can get for it and disappear from our world, while the second may be left at liberty. Thus, black holes should be the source of the stream of elementary particles, which is known as Hawking radiation. Because of this emission black holes may slowly evaporate.
However, so far no traces of radiation in nature is not found.
Franco Belgiorno from the University of Milan and his colleagues said they were able to obtain the Hawking radiation, firing powerful pulses of infrared laser models the so-called metamaterial, in which the bulk refractive index changes.
Experimenters have picked up the optical properties of this material in such a way that due to the growth of the refractive index of light slows down.
By choosing appropriate parameters, you can make light waves to stay in place" - the scientists say. Thus, the experiment created an artificial event horizon, which light can not overcome.
Pairs of particles that will be born next to the horizon should behave like a particle next to this black hole - one particle of the pair may fall into the trap of the event horizon, and the second - to go farther.
In the experiment, Belgiorno and his colleagues have actually observed the radiation with a wavelength of 850 nanometers, although the initial laser radiation had a wavelength of 1055 nm.
The authors note that they have excluded all other possible nehokingovskie radiation sources, and they actually saw an artificial radiation of black holes.
Astrophysicists have discovered a galaxy that has a super massive black hole is not located in the center, as predicted by theory, but little to the side. Article scientists outlining the discovery appears in the Journal of The Astrophysical Journal Letters, and its summary is provided in a press release from the Florida Institute of Technology, whose staff participated in.
The object of research of astrophysicists served galaxy M87, which is located at a distance of 60 million light-years from Earth in the constellation Virgo. Analysis of surveillance data obtained Hubble Space Telescope, has revealed that the central black hole of the galaxy is not exactly in the center, as predicted by theory.
Scientists offer several possible explanations for this phenomenon. Thus, according to one version, the wrong location hole is the result of merging galaxy M87 with a smaller neighbor. During the merger, super massive black holes in galactic centers are also merged. The resulting hole in this process, "withdrew" the correct position.
According to another version, the central hole can shift the emission of matter - jets - in the vicinity of the black hole (in this galaxy observed jets of a few thousand light-years). According to researchers, when scientists discovered the effect will be quite common in the
From Einstein's relativity theory the existence of these unusual objects to be the inevitable. Gravitational forces associated with the physical properties of space itself. It turns out that any body not just exists in space itself, but changes around its geometry.
In everyday life we do not notice a curved space, because we have to deal with relatively small masses, but in outer space objects can have an enormous weight - hence the powerful gravitational field that bends space, just as a massive ball bends taut fabric.
On such a surface some light items will slide in the direction of the ball, as though attracted to him. Powerful gravitational field of a massive star so much squeezes her stuff, which not only matter, but even the radio waves can not escape from the star, and it ceases to be visible. Everything - the substance of any kind of radiation - will be like to fall into an invisible hole.
In a black hole can become massive stars (larger than our sun in a few times!) For their catastrophic compression - the collapse. Star collapsar, it is a black hole, picks up radiation from the outside, but she does not let out any radiation. Time and space in the collapsar get amazing properties: They shrink to one point, in fact, cease to exist. To an observer, would be the "edge" of a black hole, there is no distance around, there is no past, no present or future.
Group of Italian scientists in the lab received the radiation of a black hole, which was first predicted by physicist Stephen Hawking in 1974.
According to existing ideas, the universe is filled permanently nascent pairs of particles and antiparticles. Shortly after birth, they annihilate each other, and the balance is not disturbed. However, close to black holes, the situation may change.
Black holes arising from gravitational collapse of massive stars have such strong gravity that it can not be overcome, not exceeding the speed of light. No facilities or radiation can not escape from overseas impact of the black hole, which was called the event horizon.
Hawking has predicted that the fate of the particles produced near the event horizon, can be very different - one of the pair can get for it and disappear from our world, while the second may be left at liberty. Thus, black holes should be the source of the stream of elementary particles, which is known as Hawking radiation. Because of this emission black holes may slowly evaporate.
However, so far no traces of radiation in nature is not found.
Franco Belgiorno from the University of Milan and his colleagues said they were able to obtain the Hawking radiation, firing powerful pulses of infrared laser models the so-called metamaterial, in which the bulk refractive index changes.
Experimenters have picked up the optical properties of this material in such a way that due to the growth of the refractive index of light slows down.
By choosing appropriate parameters, you can make light waves to stay in place" - the scientists say. Thus, the experiment created an artificial event horizon, which light can not overcome.
Pairs of particles that will be born next to the horizon should behave like a particle next to this black hole - one particle of the pair may fall into the trap of the event horizon, and the second - to go farther.
In the experiment, Belgiorno and his colleagues have actually observed the radiation with a wavelength of 850 nanometers, although the initial laser radiation had a wavelength of 1055 nm.
The authors note that they have excluded all other possible nehokingovskie radiation sources, and they actually saw an artificial radiation of black holes.
Astrophysicists have discovered a galaxy that has a super massive black hole is not located in the center, as predicted by theory, but little to the side. Article scientists outlining the discovery appears in the Journal of The Astrophysical Journal Letters, and its summary is provided in a press release from the Florida Institute of Technology, whose staff participated in.
The object of research of astrophysicists served galaxy M87, which is located at a distance of 60 million light-years from Earth in the constellation Virgo. Analysis of surveillance data obtained Hubble Space Telescope, has revealed that the central black hole of the galaxy is not exactly in the center, as predicted by theory.
Scientists offer several possible explanations for this phenomenon. Thus, according to one version, the wrong location hole is the result of merging galaxy M87 with a smaller neighbor. During the merger, super massive black holes in galactic centers are also merged. The resulting hole in this process, "withdrew" the correct position.
According to another version, the central hole can shift the emission of matter - jets - in the vicinity of the black hole (in this galaxy observed jets of a few thousand light-years). According to researchers, when scientists discovered the effect will be quite common in the
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