A black hole: The ultimate space
... The horizon of a black hole When light particles (photons) are emitted from a black hole, they perform work against gravity. This work reduces the energy of the photons. The lower energy implies a red-shift. There is a sphere around a black hole called the horizon, where the photons lose all of the ...
... The horizon of a black hole When light particles (photons) are emitted from a black hole, they perform work against gravity. This work reduces the energy of the photons. The lower energy implies a red-shift. There is a sphere around a black hole called the horizon, where the photons lose all of the ...
A black hole
... How do we know about black holes ? • We can’t see a black hole directly, because light cannot escape from it. However, if a nearby star orbits around the black hole we can detect the black hole by its gravity. • The mass of a black hole is obtained from the orbit and the velocity of the visible sta ...
... How do we know about black holes ? • We can’t see a black hole directly, because light cannot escape from it. However, if a nearby star orbits around the black hole we can detect the black hole by its gravity. • The mass of a black hole is obtained from the orbit and the velocity of the visible sta ...
File
... Purity? Absence of drama? EFT outside the horizon? Something else, like quantum mechanics for the infalling observer? ...
... Purity? Absence of drama? EFT outside the horizon? Something else, like quantum mechanics for the infalling observer? ...
Apparent versus Event Horizon
... away from it. However, some light rays that are moving away at a given instant of time may find themselves trapped later if more matter or energy falls into the black hole, increasing its gravitational pull. The event horizon is traced out by "critical" light rays that will never escape or fall in. ...
... away from it. However, some light rays that are moving away at a given instant of time may find themselves trapped later if more matter or energy falls into the black hole, increasing its gravitational pull. The event horizon is traced out by "critical" light rays that will never escape or fall in. ...
Black Hole
... – All objects moving at constant velocity have the same laws of physics – The speed of light is constant for all observers ...
... – All objects moving at constant velocity have the same laws of physics – The speed of light is constant for all observers ...
Solution Set
... The easiest way to tell if it is a black hole is if the mass of the object is measured to be larger than 3 solar masses. To measure this, Alice would need to know the orbital velo ...
... The easiest way to tell if it is a black hole is if the mass of the object is measured to be larger than 3 solar masses. To measure this, Alice would need to know the orbital velo ...
NOVA - Black Holes
... If an object is much, much more massive than the Earth or the Sun it could warp the fabric so much, it would create an actual ____________ in space-time. hole Space, itself, is ______________ inside the black hole. falling What happens to the matter that goes inside the surface of the black hole? It ...
... If an object is much, much more massive than the Earth or the Sun it could warp the fabric so much, it would create an actual ____________ in space-time. hole Space, itself, is ______________ inside the black hole. falling What happens to the matter that goes inside the surface of the black hole? It ...
Slides2 - WordPress.com
... fluctuations, vacuum space is full of particle-antiparticles which are created and rapidly annihilate by recombining. This may happen also near the black hole horizon where one of the created pairs may fall into the black hole and the other one has to escape toward infinity because of momentum conse ...
... fluctuations, vacuum space is full of particle-antiparticles which are created and rapidly annihilate by recombining. This may happen also near the black hole horizon where one of the created pairs may fall into the black hole and the other one has to escape toward infinity because of momentum conse ...
Black Holes!
... source of the name – a black hole looks dark because no light (or anything else) can come from it. ...
... source of the name – a black hole looks dark because no light (or anything else) can come from it. ...
Neutron Stars and Black Holes - School
... Black Holes Before any evidence of black holes existed they were known to be a theoretical possibility. After a supernova explosion there remains an incredibly dense neutron star. If the mass of the Sun from which it originated was great enough then the neutron star could be a black hole. The gravit ...
... Black Holes Before any evidence of black holes existed they were known to be a theoretical possibility. After a supernova explosion there remains an incredibly dense neutron star. If the mass of the Sun from which it originated was great enough then the neutron star could be a black hole. The gravit ...
Facts - short version
... In the centre of some galaxies is a black hole. Everything nearby gets pulled into a black hole; stars, dust clouds, even light – it all gets sucked in and disappears. ...
... In the centre of some galaxies is a black hole. Everything nearby gets pulled into a black hole; stars, dust clouds, even light – it all gets sucked in and disappears. ...
Supermassive black holes
... density as the Earth, and whose diameter should be two hundred and fifty times larger than that of the Sun, would not, in consequence of its attraction, allow any of its rays to arrive at us; it is therefore possible that the largest luminous bodies in the universe may, through this cause, be invisi ...
... density as the Earth, and whose diameter should be two hundred and fifty times larger than that of the Sun, would not, in consequence of its attraction, allow any of its rays to arrive at us; it is therefore possible that the largest luminous bodies in the universe may, through this cause, be invisi ...
ppt
... Idea of an object with gravity so strong that light cannot escape first suggested by Rev. John Mitchell in 1783. ...
... Idea of an object with gravity so strong that light cannot escape first suggested by Rev. John Mitchell in 1783. ...
90737_RQ_BlackHole12A
... ____16. Once you cross the ____________ of a black hole, there is no escape. a. event horizon b. disk c. core d. singularity ____17. At the __________ of a black hole, space and time come to an end. a. event horizon b. disk c. core d. singularity ...
... ____16. Once you cross the ____________ of a black hole, there is no escape. a. event horizon b. disk c. core d. singularity ____17. At the __________ of a black hole, space and time come to an end. a. event horizon b. disk c. core d. singularity ...
763620S STATISTICAL PHYSICS Solution Set 8 Autumn
... wherepA = 4πR2 is the surface area of the black hole, with R = 2GM/c2 the Schwarzschild radius, and lP = h̄G/c3 is the Planck length, and the gravitation constant G = 6.673 × 10−11 Nm2 /(kg)2 . (a) Calaculate the temperature of the black hole as a function of mass using thermodynamical identities. ( ...
... wherepA = 4πR2 is the surface area of the black hole, with R = 2GM/c2 the Schwarzschild radius, and lP = h̄G/c3 is the Planck length, and the gravitation constant G = 6.673 × 10−11 Nm2 /(kg)2 . (a) Calaculate the temperature of the black hole as a function of mass using thermodynamical identities. ( ...
black holes blog
... Black Holes Black holes don’t really represent what their name implies. They are not just a collection of empty space. They are a great amount of matter packed into a very small area. It’s like a star ten times more massive than the sun that is condensed into a sphere the size of a large city. This ...
... Black Holes Black holes don’t really represent what their name implies. They are not just a collection of empty space. They are a great amount of matter packed into a very small area. It’s like a star ten times more massive than the sun that is condensed into a sphere the size of a large city. This ...
Hawking radiation
Hawking radiation is black body radiation that is predicted to be released by black holes, due to quantum effects near the event horizon. It is named after the physicist Stephen Hawking, who provided a theoretical argument for its existence in 1974, and sometimes also after Jacob Bekenstein, who predicted that black holes should have a finite, non-zero temperature and entropy.Hawking's work followed his visit to Moscow in 1973 where the Soviet scientists Yakov Zeldovich and Alexei Starobinsky showed him that, according to the quantum mechanical uncertainty principle, rotating black holes should create and emit particles. Hawking radiation reduces the mass and energy of black holes and is therefore also known as black hole evaporation. Because of this, black holes that lose more mass than they gain through other means are expected to shrink and ultimately vanish. Micro black holes are predicted to be larger net emitters of radiation than larger black holes and should shrink and dissipate faster.In September 2010, a signal that is closely related to black hole Hawking radiation (see analog gravity) was claimed to have been observed in a laboratory experiment involving optical light pulses. However, the results remain unverified and debatable. Other projects have been launched to look for this radiation within the framework of analog gravity. In June 2008, NASA launched the Fermi space telescope, which is searching for the terminal gamma-ray flashes expected from evaporating primordial black holes. In the event that speculative large extra dimension theories are correct, CERN's Large Hadron Collider may be able to create micro black holes and observe their evaporation.