Einstein in 1916:" On the Quantum Theory of Radiation"
... Wien’s displacement law. In addition, the latter implies that the energy difference εn − εm between two internal energy states of the atoms in equilibrium with thermal radiation has to satisfy Bohr’s frequency condition: εn − εm = hνnm . Einstein was very pleased by this derivation, about which he w ...
... Wien’s displacement law. In addition, the latter implies that the energy difference εn − εm between two internal energy states of the atoms in equilibrium with thermal radiation has to satisfy Bohr’s frequency condition: εn − εm = hνnm . Einstein was very pleased by this derivation, about which he w ...
Chapter 14 Neutron Stars and Black holes
... 1. Has the existence of neutron stars been sufficiently tested to be called a theory, or should it be called a hypothesis? What about the existence of black holes? 2. Why would you expect an accretion disk around a star the size of the sun to be cooler than an accretion disk around a compact object? ...
... 1. Has the existence of neutron stars been sufficiently tested to be called a theory, or should it be called a hypothesis? What about the existence of black holes? 2. Why would you expect an accretion disk around a star the size of the sun to be cooler than an accretion disk around a compact object? ...
Which is it: Dark Matter or Modified Gravity?
... At the time of big-bang-nucleosynthesis (BBN), we have guaranteeing that the production of elements agrees with observation. After decoupling until stellar and galaxy formation when and the MOG non-relativistic acceleration law sets in to explain the rotation curves of galaxies and the dynamics of ...
... At the time of big-bang-nucleosynthesis (BBN), we have guaranteeing that the production of elements agrees with observation. After decoupling until stellar and galaxy formation when and the MOG non-relativistic acceleration law sets in to explain the rotation curves of galaxies and the dynamics of ...
NCEA Level 2 Earth and Space Science (91192) 2015
... leftover gas and dust particles. These particles rotate around the young star and flatten into a gaseous protoplanetary disk around the star. A protoplanetary disk is a flattened disk shape. This contains rocky particles that condense together due to gravity. The disk is swirling (to conserve angula ...
... leftover gas and dust particles. These particles rotate around the young star and flatten into a gaseous protoplanetary disk around the star. A protoplanetary disk is a flattened disk shape. This contains rocky particles that condense together due to gravity. The disk is swirling (to conserve angula ...
Coding Einstein`s Legacy - the Neukom Institute
... a lot of radio signals. The object became known as Sagittarius A* (pronounced “A-star”), or Sgr A* for short. Improved resolution of images of this region showed that Sgr A* was black, not emitting any light, but surrounded by many stars. From 1992 to 2002, a group led by Rainer Schödel of the Max ...
... a lot of radio signals. The object became known as Sagittarius A* (pronounced “A-star”), or Sgr A* for short. Improved resolution of images of this region showed that Sgr A* was black, not emitting any light, but surrounded by many stars. From 1992 to 2002, a group led by Rainer Schödel of the Max ...
Introduction to Galaxies and Cosmology Exercises 2
... 7. For every mass m which is swallowed by a black hole (via an accretion disk, say), an amount of energy νmc2 is liberated, where ν is the efficiency of the process. A value of ν = 0.1 is realistic. At what rate Ṁ would a supermassive black hole have to swallow mass to produce the luminosity L = 10 ...
... 7. For every mass m which is swallowed by a black hole (via an accretion disk, say), an amount of energy νmc2 is liberated, where ν is the efficiency of the process. A value of ν = 0.1 is realistic. At what rate Ṁ would a supermassive black hole have to swallow mass to produce the luminosity L = 10 ...
Modave Lectures on Fuzzballs and Emission from the D1
... Our strategy to see the Hawking effect is to look at the infalling vacuum and study how it looks in terms of the outgoing modes at late times in a collapsing black hole spacetime. This is most easily done by looking at the ‘time reversed’ situation, that is, by propagating outgoing waves backward i ...
... Our strategy to see the Hawking effect is to look at the infalling vacuum and study how it looks in terms of the outgoing modes at late times in a collapsing black hole spacetime. This is most easily done by looking at the ‘time reversed’ situation, that is, by propagating outgoing waves backward i ...
Word doc - UC-HiPACC - University of California, Santa Cruz
... postdoctoral researcher Ke-Jung Chen stumbled on the unanticipated discovery that some primordial supermassive stars could explode without leaving any black hole or other stellar remnant behind. Chen had been fascinated by supermassive black holes since grad school at the University of Minnesota. Ev ...
... postdoctoral researcher Ke-Jung Chen stumbled on the unanticipated discovery that some primordial supermassive stars could explode without leaving any black hole or other stellar remnant behind. Chen had been fascinated by supermassive black holes since grad school at the University of Minnesota. Ev ...
black holes are created when stars collapse and die from burning its
... • the process of pulling matter into its core releases a giant amount of energy, which causes surrounding material to disperse, so it doesn’t grow as fast • once all the starts burn out in 100000000000000000000000000000000000000000000000000000000000000000 years (100 vigintillion years), then black h ...
... • the process of pulling matter into its core releases a giant amount of energy, which causes surrounding material to disperse, so it doesn’t grow as fast • once all the starts burn out in 100000000000000000000000000000000000000000000000000000000000000000 years (100 vigintillion years), then black h ...
powerpoint
... 2) Very careful studies of the velocities of galaxies should be able to reveal if the rate of expansion is slowing down. However, the latest studies found a big surprise: the rate of expansion is increasing! If true, the universe will probably expand forever, but the results are only a couple of yea ...
... 2) Very careful studies of the velocities of galaxies should be able to reveal if the rate of expansion is slowing down. However, the latest studies found a big surprise: the rate of expansion is increasing! If true, the universe will probably expand forever, but the results are only a couple of yea ...
Lecture 2: Gravitational wave sources
... have produced tensor modes that generate nonzero curl in the polarization from low-ℓ modes in the cosmic microwave background. The expected levels will be such that ground-based detectors should see them in the next few years (if Planck doesn’t see them first, which is possible but not at all guaran ...
... have produced tensor modes that generate nonzero curl in the polarization from low-ℓ modes in the cosmic microwave background. The expected levels will be such that ground-based detectors should see them in the next few years (if Planck doesn’t see them first, which is possible but not at all guaran ...
Characteristics Of The Universe Origin Of Universe
... of stars that were so small and massive that particles of light could not escape. Thus, the star would be black. How Can Astronomers Find Black Holes If They Cannot See Them? The key to finding black holes is their immense gravitational power. One way to find black holes is to observe matter moving ...
... of stars that were so small and massive that particles of light could not escape. Thus, the star would be black. How Can Astronomers Find Black Holes If They Cannot See Them? The key to finding black holes is their immense gravitational power. One way to find black holes is to observe matter moving ...
Lecture 6
... Sources of radiation Most important type of radiation is blackbody radiation. This is radiation that is in thermal equilibrium with matter at some temperature T. Lab source of blackbody radiation: hot oven with a small hole which does not disturb thermal equilibrium inside: ...
... Sources of radiation Most important type of radiation is blackbody radiation. This is radiation that is in thermal equilibrium with matter at some temperature T. Lab source of blackbody radiation: hot oven with a small hole which does not disturb thermal equilibrium inside: ...
Research Powerpoint - Department of Astronomy
... surveys to binary stars to the shape of dark matter halos. Pictured above are recently discovered “binary” stars. Such very wide systems are easily perturbed and possibly disrupted by passing stars and, possibly, dark-matter subhalos. The constellation of Ursa Major (top middle) contains six bright ...
... surveys to binary stars to the shape of dark matter halos. Pictured above are recently discovered “binary” stars. Such very wide systems are easily perturbed and possibly disrupted by passing stars and, possibly, dark-matter subhalos. The constellation of Ursa Major (top middle) contains six bright ...
CHAPTER 13 Neutron Stars and Black Holes Clickers
... Question 9 The equivalence between an accelerating windowless elevator in space and a stationary elevator in a gravity field is a prediction of Newton’s theory of gravity. explains why elevators don’t work in space. explains why E = mc2 is true. helps explain Einstein’s theory of gravity. e) All of ...
... Question 9 The equivalence between an accelerating windowless elevator in space and a stationary elevator in a gravity field is a prediction of Newton’s theory of gravity. explains why elevators don’t work in space. explains why E = mc2 is true. helps explain Einstein’s theory of gravity. e) All of ...
The flashy disappearance of a star falling behind the horizon of a
... section 2, and section 3 describes the properties of the star as the light source. The results of numerical simulations are shown in 26 figures and some phenomena responsible for their appearance are discussed in section 4. It is possible that such phenomena are relevant for the description of certa ...
... section 2, and section 3 describes the properties of the star as the light source. The results of numerical simulations are shown in 26 figures and some phenomena responsible for their appearance are discussed in section 4. It is possible that such phenomena are relevant for the description of certa ...
Chapter 5 The Nature of Light
... Although Isaac Newton suggested that light was made of tiny particles 130 years earlier, Thomas Young demonstrated in 1801 that light has wave-like properties. He passed a beam of light through two narrow slits which resulted in a pattern of bright and dark bands on a stream. This is the ...
... Although Isaac Newton suggested that light was made of tiny particles 130 years earlier, Thomas Young demonstrated in 1801 that light has wave-like properties. He passed a beam of light through two narrow slits which resulted in a pattern of bright and dark bands on a stream. This is the ...
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.