Please explain the Quantum Theory of light?
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Light shows dual behavior as both wave and particle. The wave behavior is observed when we see defraction of light when it passes through slits. Also, we can observe light showing particle behavior. These small packets of light are called quanta, hence the lable quantum.
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Heisenberg's Uncertainty Principle is science.  Allow me to explain why.\n\nIt was observed that there were limits on measurements made at the smallest levels.  When Planck pointed out that light acted as if it were small particles--quantum, in the singular, and quanta in the plural--Heisenberg used some of the stuff inherent in the physics developed from Planck's work to explain the uncertainties of the measurement, and indeed to go one step farther and show how using electromagnetic radiation to sense things imposed specific limits on how well you could measure things, a developement that matched what had been observed.\n\nSO!  We have observation; we have development of theory; we have measuring of theory against observation, and seeing whether or not it matched, which it did.\n\nAt the level of abstraction in that last paragraph, this is pretty much the same as science elsewhere...
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Yes...thus far, it IS the simplest and best explanation of gravity...quantum mechanics doesn't explain gravity at all.  What is NOW needed is a theory of "everything" that can link relativity to QM so that they're BOTH compatible.
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Quantum theory and its relation with general theory of relativity
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Hi, \n\nThat's too much like real work, but think about it like breaking pool balls in classical, and wave interference with quantum. \n\nHope that helps, \nMatt
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A good website on quantum mechanics: http://en.wikipedia.org/wiki/Quantum_mechanics\n\nAlso, if you are intrigued by the cosmological theory of the universe, The Life of the Cosmos by Lee Smolin is an excellent read.
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This is almost a semantic question - what do we mean by "digital"\n\nBut the answer would have to be digital since photons are "individual" quanta. Molecules (in your eye) absorb one quantum of energy at a time; send one nerve impulse at a time etc.\n\nOn the other hand, quanta of differing wavelengths seem to excite the same molecules leading to a rather analog interpretation of color!
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When the light speeds up it gains mass, so it should loose mass when it slows down.\n\nSo you are right. Light has zero rest mass. So it will be as if it was non existant when its at rest. But we know when light hits any other particles it converts to energy and reveals its presense ( We humans also detect light with eyes, but its similar process of how objects get hot in summer with light ).\n\nNewton's Corpslcular theory can be very good classical explantion of mass/energy relation of light if every were normal classical photon. But we all know that Newton was wrong, and light will not change its direction slowly to conserve energy, but when it hits any smooth surface it retracts immediately. So its velocity at that point of hitting is zero for very very very short periods of time, and again its back to light speed. So your question does not have a classical or quantum explantion, but reltivity theory can be used to understand it.
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its like we have developed the properties of particles and waves much before than we be knowing that actually everthing in the universe is having both properties.\n\nlight has a nature which can neither be defined as of wave and nor that of particle. hence, in old science terms light is both the particle and wave. \n\nif you are much intrested in this phenomenon then read about string theory which states that there are two things important\n1. the object\n2. the relation \n\nwe in neutoneon science have concentrated on 1st. but actually the nature can only be studied with the help of 2nd.
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Light is both a wave and a particle at the same time.\n\nLight is a form of energy, and depending on how you observe it, it exibits both properties of an electromagnetic wave or a particle (photon).\n\nElectromagnetic waves do not require a medium in which to propigate, they are a self propigating electric and magnetic field, allowing it to travel through a vacuum.\nEvidence of this can been seen in diffraction patterns, such as when you look at the rainbow effect on a CD.\n\nPhotons are a "quantized" amount of light.  These light partciles are absorbed or given off by atoms in something called the "photoelectric effect" (which Einstien received a nobel prize for).\nEvidence for this can be seen in things like LEDs or when you study the structure of the atom.
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The basic physics behind a laser was thought up by Einstein (that guy was everywhere!) but the first ones were not actually built until the middle of the 20th century.\n\nLaser is an acronym for Light Amplification via Stimulated Emission of Radiation. "Radiation" just means light, and "Stimulated Emission" is a property of some gases because of Quantum Mechanics.\n\nIn QM we know that electrons can only be in certain "orbit" in an atom, more properly called energy levels. When an electron makes a quantum leap from one energy level to another lower level (assuming there is a lower level) It will release a photon (sort of a piece of light) with a very specific frequency. (Frequency and wavelegth are inversely proportion, so one frequency corresponds to one wavelength.)\n\nFor example in hydrogen if an electron in the second lowest energy level drops down to the very lowest level it will emit a photon with a wavelength of 656.3 nanometers, which turns out to be reddish light. From the third lowest to the lowest the photon wavelength is 486.1 nm, which is blue green.\n\nThe point being that an atom can emit light only in very precise frequencies, and not any old frequency.\n\nEinstein developed the concept of "stimulated emission" which is a much more complicated consequence of Quantum Mechanics. It says that if a photon with a transition wavelengh passes close to an excited atom, it will "stimulate" the excited atom to also emit at that frequency.\n\nSo in the hydrogen example, lets say the electron is in the 3rd level. If it were to drop to the lowest level the photon would be 486 nm. While the electron is just hanging around on the third level, if some random photon comes flying past with a wavelength of 486 nm this will stimulate the electron to drop and emit its own photon of that frequency. From the outside it looks like one photon went past an atom and then there were two photons.\n\nTherefore the idea in a laser is to get a lot of atoms into an excited state - which is hard, they would rather be in their ground state - and then wait for one of the atoms to emit a photon. This will prompt more atoms to emit photons, and all those will prompt even more to emit photons, etc. etc. The result being "light amplification via the process stimulated emission."\n\nThe benefits of a laser include the light being all very nearly at one wavelength, and all the light being in phase.\n\nFor a CO2 laser the output light has a wavelength of 10,600 nm, which is in the infrared part of the spectrum and not visible to the human eye. The gas inside a CO2 laser consists of, well, CO2 and also Nitrogen and Helium. The transitions are not simple atomic ones as in the example of hydrogen I gave, but molecular transitons of the CO2 molecule. The basic physics is the same, though.\n\nThese other gases are needed as part of the difficult process of getting a lot of the CO2 molecules into an excited state and keep them there long enough so that they will emit photons via the stimulated emission process.
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The frequency of light and its wavelength have an inverse relationship.  As the frequency of light increases, the wavelength decreases.\nThe frequency is the number of 'cycles' per unit time, and the wavelength is how far the wave propagates in that same time.  At a constant speed, the shorter the higher the frequency (very short time durations between cycles), the smaller the wavelength.\n\nThe energy contained within a single photon of light is given by Planck's equation,\nE = hv\nwhere E is the energy, h is Planck's constant, and v is the frequency of light.\nThe equation can be re-written as,\nE = h * c / lambda\nWhere c is the speed of light in a vacuum, and lambda is the wavelength of light.\n\nYou can see that as the frequency of the light increases (or when the wavelength decreases), the energy contained within a photon of light increases.  The higher the frequency of light, the more energy the light carries.  For example, high frequency X-rays carry much more energy than low frequency radio waves.\n\nh = 6.626 E-34 J s
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Mit has open courseware on their website.  They've been videotaping the classes, but they don't have this for the quantum physics classes yet.  If you just want basic information, then you can check out some of the other physics.
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Believe it or not, we already have it and use it everyday. I want to answer this in detail, but I cant disclose the true nature of how light travels until I publish.\nI will say that light that is propagated within a closed system can and does move at superluminal speeds relative to a location outside the closed system.\n\nI know-Everybody has a theory, but I can also explain why light bends at every instance without once referring to the fabric of space/time.\n\nWhat if Einstein was WRONG...errr...ok... (just so I dont offend anyone) not completely correct? What if light actually didnt travel by propelling itself into the electromagnetic field created by....itself? What if there was no such thing as a pure vacuum with zero atomic content? (by the way, there is no such vacuum.)\nResearch it, its true, there are always atoms left over to fill the space left by the vacated ones.\nDon't you find that at least a little interesting?  No such thing as a pure vacuum?
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Light of a form of energy. Energy is the only thing in universe. There are different forms for energy. Light is just another form of energy - A radiation. \n\n   Hope you know that matter (whatever it is) is just Energy got trapped in space. Matter produces energy in-order to maintain its stability. That may be a chemical reaction, a nuclear reaction or even annihilation. This released energy may contain light energy and so light is produced.\n\n  There are different theories to explain what is light.\n\n1. Newtons Corposcular theory - Light is a stream of corpusles (small balls) - and thus exhibit a particle nature.\n\n2. Hygen's Wave theory - Light is comprised of compressions and rare-fractions and thus exhibit a wave nature.\n\n3. Maxwell's Electro-Magnetic theory - Light is a combination of electrical and magnetic field perpendicular to each other - travells in a straight line in a constant speed.\n\n4. Max- Plank's Quantum theory - Light cotains packets of energy - called photons. The packets are called Quanta\n\nThese theories are quite old and some how relevent even in theses days. Today we know that light exhibits both particle and wave nature.\n\nLight exists for ever. - It is never created nor destroyed.\nIt only changes its form.
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Think of Einstiens theory of relitivity E=((MC)squared) Where C = the speed of light and M = th electrons flowing from the electric source to the bulb = E (the ability to do work) wich results in theroy the light bending around the vehicle eirgo the light bends becaus both the light and the vechile are travling at the same speed.
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Quantum Theory, also quantum mechanics, in physics, a theory based on using the concept of the quantum unit to describe the dynamic properties of subatomic particles and the interactions of matter and radiation. The foundation was laid by the German physicist Max Planck, who postulated in 1900 that energy can be emitted or absorbed by matter only in small, discrete units called quanta. Also fundamental to the development of quantum mechanics was the uncertainty principle, formulated by the German physicist Werner Heisenberg in 1927, which states that the position and momentum of a subatomic particle cannot be specified simultaneously.