what is quantum electro dynamics?
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Quantum electrodymanics is the relativistic quantum theory of electromagnetism.  it was developed by Richard Feynman, Julian Schwinger, and Sin-Itiro Tomonaga in the 1940's and they shared a Nobel prize in 1965 for its development. It is, arguably, the most precisely verified scientific theory yet devised, making predictions (of atomic energy levels and of the magnetic moment of the electron - R. Van Dyck, Jr., P. Schwinberg, and H. Dehmelt, Phys Rev. Lett. 59, 26 (1987); P. Milonni, p. 108, The Quantum Vacuum\nAcademic Press, San Diego, CA, 1994) that have been experimentally validated to 1 part in 10^12!  \n\n1 part in 10^12 is about the ratio of the diameter of a large bacterial cell to the diameter of the Earth.
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It depends on what you mean by a "quantum field."\n\nOne sense, which is wrong, is used by various cranks to add the illusion of scientific accuracy. They use it more or less randomly to spice up their descriptions. Other popular words are: vibration, frequency, and zero-point energy (all of which are actual terms when used in the right context.)\n\nThe other (correct) sense is used in modern physics. But while there is Quantum Field Theory there is not  a physical entity called a simply a "quantum field." You need to have a field of something, for instance electromagnetism, and then treat it using the precepts of Quantum Mechanics. Other more complicated quantum fields are used to describe electrons inside a superconductor.\n\nAs for Tesla he was an excellent inventor who was unlucky in business and due to the machinations of rivals. He was correct in understanding the AC was superior to DC for transmitting electrical current (contrary to Edison), and did a lot of early work in Radio - probably before Marconi. \n\nUnfortunately today various crank scientific theories and crackpot "free energy" inventions toss his name around, using his reputation as being "right but unrewarded" to someone make their own theories seem right. (In other words, "people didn't listen to Tesla, so when they say I am a crank they are just a wrong" - common crank logic.)\n\nSo, I don't think there is anything here to investigate, I'm afraid. Tesla didn't pull energy from a "quantum field."
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Quantum mechanics is a mathematical theory that can describe the behavior of objects that are roughly 10,000,000,000 times smaller than a typical human being. Quantum particles move from one point to another as if they are waves. However, at a detector they always appear as discrete lumps of matter. There is no counterpart to this behavior in the world that we perceive with our own senses. One cannot rely on every-day experience to form some kind of "intuition" of how these objects move. The intuition or "understanding" formed by the study of basic elements of quantum mechanics is essential to grasp the behavior of more complicated quantum systems. \n\n\nPlease visit the below url for moe information
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It's a measure of energy where one electron volt is equal to 1.6 x 10^-19 Joules or 0.00000000000000000016 Joules.\n\nIt is the energy required to move an electron along a potential difference of 1 volt
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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.
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Quantum physics... Try those links in the way I'm ordering them...\nhttp://www.jracademy.com/~jtucek/science/what.html\n\nhttp://www.hpwt.de/Quantene.htm\n\nhttp://en.wikipedia.org/wiki/Quantum_theory\n\nhttp://www.pa.msu.edu/courses/1997spring/PHY232/lectures/quantum/quantum_def.html
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I hate to admit it, but only one of these theories existed when I was in school.  SHMO is in the realm of computer assisted quantum chemistry that has sprung up in the last few decades.  I'm too old of a dog for this level of stuff anymore.\n\nPlease accept my apologies!
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Quantum mechanics is fascinating, as Einstein's famous quote that "God does not play dice with the universe" is turned on its head.  The random nature associated with the inner workings of atoms and quarks is astonishing when one considers that despite all of the unpredictability of subatomic activity, things in the macroscopic world follow predictable patterns that seem to defy common sense.
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Newtownian mechanics deals with behavior of macroscopic objects; quantum mechanics deals with the behavior of microscopic objects.  It’s called “quantum” because energy comes in discrete, tiny quantities (quanta) that radically affect the behavior of objects such as atoms or protons or electrons.  Instead of being able to describe reality as straightforward cause-and-effect (à la Newton), quantum mechanics ends up taking one down twisted roads of probability in terms of “wave functions,” which could be considered oscillations of a sort, but not exactly oscialltions like waves in a pond or even electric fields in light.\n\nEinstein made contributions to quantum mechanics (most notably his work regarding the quantization light into packets subsequently dubbed “photons,” for which he was awarded a Nobel Prize), but he never quite trusted its non-causal nature.\n\n\nRyan Wyatt\nRose Center for Earth & Space\nNew York, New York
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This is one of those wierd questions in Quantum Mechanics where there is no way to visualize the answer. Our brains, understandably, have evolved to handle falling rocks, jumping tigers, and other macroscopic objects. We have numerous hardwired responses to these things which follow classical, Newtonian Physics.\n\nOn the atomic and subatomic scales where objects behave according to the laws of Quantum Mechanics things are different. An electron can behave like a wave in this experiment, but a particle in another experiments. According the classical physics (and our macroscopic-loving brain's "common sense) nothing can be *both* a particle and a wave. \n\nSo what is an electron? A wavicle? A partiave? \n\nNope. An electron is a, well, an electron. Sometime it will behave *exactly* like a wave, other times it will behave *exactly* like a particle. Never will it behave like some intermeditate or mixed state.\n\nThe problem - to the extent there is a problem - is that we cannot visiualize this. There is no way to form a picture in our heads the same way we can form a picture of a ball flying though the air. Our brains are meant to operate on macroscopic phenomena, and subatomic phenomena just behave differently.\n\nPresumably some other alien species could have some sort of mind, or mind-like thing, for which the whole wave-particle duality thing just makes perfect sense! But presumably this aliens would be confused by what are to us the simple motions of a ball flying through the air.\n\nSo, in the Copenhagen Interpretation of Quantum Mechanics, there is no sense in which the "other forms" of an object change after a wavefunction is collapsed. That this seems to be a problem is more a function of our brains and how they have evolved.\n\n\n(As an aside, it should be said that it is possible to understand the mathematics underlying Quantum Mechanics. And to be able to use this math to make extremely accurate predictions of how electrons, atoms, etc. will behave. These predictions can be tested experimentally and Quantum Mechanics holds up extremely well. \n\nSo while QM is very wierd, there is an enormous amount of evidence that it is correct.)
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It is the quantum mechanical description of conservation of energy principle.
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This is because the nuclear attraction over the electrons increases.\nRemember Coulombs law of electro_nuclear forces.
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the hamiltonian is the fundamental quantity in hamiltonian dynamics, which is a rather advanced form of basic, classical mechanics.  the essence of hamiltonian dynamics is that energy is the fundamental quantity of motion, whereas in a newtonian system, forces and momenta are the fundamental quantities.  neither is more correct - if you use them properly, both should give you the same results.  however sometimes one form is easier to use than the other.\n\nessentially the hamiltonian itself is a description of the total energy of a system in any given configuration.  the basic way of defining a hamiltonian is H = L + V, where L is the total kinetic energy of the system and V is the total potential energy of the system.  of course, L and V are themselves functions of other variables - V is often a function of position, if you are talking about a conservative potential.  L is a function of the momentum or velocity.\n\nif you have a real, complex system with many atoms and many degrees of freedom, the hamiltonian is a very large and complex quantity.  usually you see hamiltonians writen down for very simple or oversimplified systems.  \n\nalso, many physical systems are "non-hamiltonian", which means that energy is not conserved within the system.  so, for example, you cannot write a hamiltonian for something that radiates heat away and out of the system.  hamiltonian dynamics are insufficient to describe that kind of thing.\n\nanyway, the Hamiltonian is called an operator because it acts on something.  in the case of the quantum-mechanical hamiltonian, the form of this operator is:  H = h^2/2m * del^2 + V\nwhere del is the differential operator d/dx + d/dy + d/dz (in cartesian coordinates).  obviously something has to come after H, because d/dx doesn't mean anything on its own!\n\nin the languages of matrices and operators, a system can be described by a *vector* where each element in the vector is some physical property - the location in space on some coordinate axis, or velocity, for example.  \n\nif you multiply some vector of size N by a matrix of size NxN, you get out another vector of size N.  so, this is like the matrix performs some "operation" on the vector and transforms it into something else.  of course the transformation depends on what's in the matrix.\n\nso, the hamiltonian is a way of describing the time evolution of something.  it is used this way in quantum mechanics - if you have some quantum mechanical system in a state, and you operate on it with a hamiltonian, you get back the state of the system at some later time.  if you look at the basic form of the schroedinger equation (- d/dt Psi = H Psi, if you leave out all the constants etc), you can read out what the meaning is:  "the rate of change of the wavefunction equals the hamiltonian acting on the wavefunction".  this means the hamiltonian tells you how the wavefunction or state of the system changes with time.\n\nyou can see an example of what the hamiltonian matrix looks like for a very simple system, the quantum mechanical simple harmonic oscillator, here:\nhttp://scienceworld.wolfram.com/physics/HamiltonianOperator.html\n\nif you are interested in learning more about hamiltonians, i would suggest you first learn about lagrangian mechanics, which is closely related, and the notion of "generalized coordinates".\n\ncheers!
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Quantum mechanics is a fundamental physical theory that replaces Newtonian mechanics and classical electromagnetism at the atomic and subatomic levels and is the underlying framework of many fields of physics and chemistry, including condensed matter physics, quantum chemistry, and particle physics. Often, it is the answer to questions when general relativity fails.
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the theory that light, and all electromagnetic radiation (radio waves, x-rays, microwaves) travels as a wave, like the ripples on a plucked string. these waves look like sine and cosine graphs.\n\n\nthis was proved to be an incomplete picture by eistein's analysis of the photoelectric effect, for which he won the nobel prize. this showed light was in fact made of particles called photons. however, quantum wave theory now tells us that all matter is both a particle and aa wave; the matter is contained in a particle, but the location of the particle is determined by a wave.
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people have this picture in their head of what an atomic electron is like - it's a little ball and it whizzes around the nucleus really fast.  but it's not really like that.  \n\nyou have to divorce from your mind the notion that the electron has a single, fixed, localized position.  instead the electron is "spread out" over space, like a big smear in three dimensions.  a lot of chemistry teachers like to fudge this bit by saying that the electron spends "more time" in areas with higher electron-cloud density, but that's not really correct.  if it were, i could see where your confusion might come from - if it was spending some time on one side of the nucleus, it must spend some time getting back to the other side.\n\nthe truth is, in quantum mechanics an electron is "delocalized".  this means that it has no real, fixed position - instead it is spread out over a region or regions of space, and in fact those regions of space need not be connected.  the electron is quite literally in both places at once, not in one place or the other.\n\nthis is a rather small effect in atomic electrons, but if you consider a conducting metal like copper, the "free electrons" that carry electricity are extremely delocalized.  every single electron is basically spread out over the entire piece of copper.  it's kind of hard to picture, but that's why quantum mechanics is hard.\n\nhope this helps.  feel free to email if you'd like to discussit more.
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It work off of Einstein's photoelectric effect. Light is an electromagetic wave propagating through space, but due to Quantum Mechanics it can also be viewed as particles. The energy of these particles, called photons, is dependent upon the frequency of the light. The higher the frequency the higher the energy. If the frequency and thus the energy of a photon is high enough it can knock an electron out of its atomic orbital. \n  Now the problem is that one can not predict in which direction the electron is going to travel, however there are special transitionary elements between the metals and non metals called semiconductors. These semiconductors are divided into two classes p-type and n-type. Now if one places a film of n-type semiconductor against a film of p-type semiconductor they produce a diode which allows electric current to only flow in one direction from the n-type side to the p-type side. So only the electrons that are knocked from the n-type side to the p-type side are compelled to stay put, but as more and more electrons are knocked over to the p-type side a a voltage potential starts to develope.