# Tag Info

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You appear to have some impression of the electric field which has given you the idea that it's some sort of bubble or something around an electron, for example. It's not. There's no real way to answer your question other than that that I can think of. It doesn't somehow fit itself through the slit or anything like that really.

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One has to distinguish between, on one hand, an orbit and an orbital motion, which are classical notions; and on the other hand, an orbital, which is a quantum mechanical notion, cf. above comment by dmckee. If the question is really Why quantum mechanics?, then have a look at e.g. this Phys.SE post and links therein. Here we will assume that OP accepts ...

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Electron in a ground state hydrogen atom has zero angular momentum $L^2$, l=0. Moon has a huge angular momentum. Therefore it is a poor comparison. If moon would have zero angular momentum, in classical physics, it would fall down and hit earth. Electron in an hydrogen atom, in l=0 state gets constantly pulled to the center, but this is countered by the ...

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In effect, it's done all the time in a transmission electron microscope. Usually it's not a simple double slit but rather a multiple slit (in the form of a crystalline lattice). This is happening in the presence of a strong and rather inhomogeneous magnetic field, produced by the microscope's objective lens. The interaction (and remember, it is an ...

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If you would measure the electron at one of the slits, then the interference patterns would no longer be formed. That is because the pattern is produced by interference of an electron amplitudes diffraction from slits 1 and 2. If you know that electron is at slit 1, it is of course no longer at slit 2, and therefore you wouldn't get the interference pattern. ...

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That is quite much the point, isn't it. Claus Jönsson of the University of Tübingen did this with electrons in 1961. In 1974 the Italian physicists Pier Giorgio Merli, Gian Franco Missiroli, and Giulio Pozzi repeated the experiment using single electrons, showing that each electron interferes with itself as predicted by quantum theory.

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I can't understand your question thoroughly. But if you connect the negative terminal of the battery to any conducting body like a metal can, then there will be a flow of charge till the potential of the negative terminal and the metal are equal because the metal body and the negative terminal are a single conducting body and a conducting body has a ...

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People have certainly measured the electron's charge and mass more than once in the last 100 years. See for example this table from the Particle Data Group, where you can find the constants you want to around 8 significant digits, much more than what was possible for Millikan. For comparison, Wikipedia claims that Millikan and Fletcher measured $e$ to be ...

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The principal advantage of using electrons is that the electron is a fundamental particle so electron-electron (or electron-positron) collisions are are well defined process that is relatively eay to describe mathematically, and very accurate measurements can be made. By contrast the proton is a composite particle. We normally describe the proton as being ...

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Very good answers above! I would just add one simple point to be more specific to your question. The LHC uses anything it can smash together just to see whats inside. The other Synchrotrons use electrons because its easy to shake radiation out of them and Synchrotron radiation is what they want to produce. The same way bumping electrons will produce photons ...

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I'm researching synchrotrons for a class project, but I can't seem to find a decent answer to one of my questions. It appears that most synchrotrons use electrons as opposed to some other charged particle, while the Large Hadron Collider uses protons instead.. The first thing that you should know is that there are two completely different uses for ...

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The quantity that determines what a particle beam may be used for is called gamma ($\gamma$). It is defined as $$\gamma = \frac{1}{\sqrt{1-\left(\frac{v}{c}\right)^2}}.$$ As $v$ gets closer to $c$, $\gamma$ gets larger without bound and equals infinity when $v = c$. Since particles in a synchrotron are moving at very close to the speed of light ...

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Even if you could cool down to absolute zero which is impossible due to third law of thermodynamics. there would still be quantum fluctuation. electron would not stop moving. it would still orbit around atom. Heisenberg uncertainty principle states that we can never precisely know the position of an electron and momentum simultaneously. so therefore ...

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Take the commutator acting on a function $f$. Then \begin{split} [ P_i , P_j ] f &= [ - i \partial_i - q A_i , - i \partial_j - q A_j ]f \\ &= ( i \partial_i + q A_i )( i \partial_j + q A_j ) f -( i \partial_j + q A_j ) ( i \partial_i + q A_i ) f \\ &= - \partial_i \partial_j + i q A_i \partial_j \, f + i q \partial_i ( ...

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Madelung's Rule: Orbitals fill from lowest energy to highest energy, so for example $\mathrm{1s,2s,2p,3s,3p,4s,}$ etc. Pauli's Exclusion Principle: No two electrons can have the same set of four quantum numbers, in the same orbital. In practice this means atomic (or molecular) orbitals can only accomodate 2 electrons, one with spin quantum number ...

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There are really two main ways of thinking about [electrons]. Quantum Mechanics describes an electron by a wave function who's squared magnitude gives the probability of finding the electron in a certain position or with a certain momentum. QFT ... describes the electron as an excitation of the electron field. Both of these models describe the ...

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Ionizing radiation is radiation that is strong enough so that, when it hits an atom or molecule, will knock off electrons. This happens even if the target object doesn't have freely mobile electrons, which leaves free radicals and broken bonds, both of which are harmful to complex biological processes. There's no selection based on electron binding energy; ...

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One has to keep in mind 1) that it is the complex conjugate square of the eigenfunction that gives the probability of finding the electron with energy E at a specific radius. 2) There are no fixed orbits in the quantum mechanical solution, only a locus of probability called orbital 3)orbitals overlap in space, it is the energy that is keeping the electron ...

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Potential energy is wrong. Even in Newtonian Mechanics it only works if the force is 1) purely a function of position and also 2) is conservative. Magnetic forces depend on velocity so they fail. And electric forces are not conservative if you aren't in statics. What you really have is kinetic energy and rest energy for the charged particle, some energy ...

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Don't forget about the rest energy, $E=mc^2$. Since a particle's intrinsic spin cannot be changed, it doesn't make sense to distinguish "intrinsic spin energy" $\frac12 I\omega^2$ (as you would compute for, say, a spinning flywheel) and the rest energy. A particle which is moving in an electric field will see a motional magnetic field. Charged particles ...

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If an electron is an excitation of the electron field, what causes the excitation to be stable? I think the best way to say it is to take a tip from topological quantum field theory: "Although TQFTs were invented by physicists, they are also of mathematical interest, being related to, among other things, knot theory and the theory of four-manifolds in ...

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The electron is stable because there is no allowed process in the quantum field theory it can undergo that would lead to its decay. Its mass is the smallest among the electron/muon/tauon, so it doesn't have enough energy on its own to turn into one of those, and all other processes you could imagine are forbidden by conservation laws - either those of energy ...

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The reason I give is simply that attraction from some opposite charge induces motion in an electron. The resistance to its flow is caused by the medium. If the medium was empty, there would be no resistance, hence empty space should conduct electricity better than copper wires! A metal wire is conductive because metals have lots of energy levels near ...

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The options 1,2 are actually physically identical because the electrons are identical particles. Once we have two electrons, we can't say which of them is "Paul" and which of them is "Peter". When the addition is slow etc., the option 1=2 violates the conservation law for the angular momentum. So it is indeed 3 that has to happen: the ion will refuse to ...

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Electrons (charge carriers in a wire) move from high electric potential (high voltage) to low electric potential(low voltage). While electrons are travelling, it is the resistors which pick the amount of electrical energy they want (per their electrical capacity) and it is not the electrons that determine how much they should drop off at each of the ...

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Observables like quantised energy levels and quantised angular momentum of an atom are obtained by finding eigensolutions of the Schrödinger Equation (here for the Hydrogen atom). Separation into three parts allows to obtain the Colatitude and Azimuthal equations which allows to calculate the quantised angular momentum of the hydrogen atom, giving rise to ...

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The question is ill-posed; the electrons "know" nothing, and voltage is not a property of the electron (other than e.g. charge, which is a property). In fact, voltage is a pretty abstract concept; it is energy divided by charge. And that means explaining an abstract term by another abstract term. Let's be more fundamental: nature shows that charges exert ...

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BEWARE THE SANDWICHES!!! :) In the spirit of math-avoidance sandwich-juggling, here's a better analogy, a visible one. The movable charges within conductive circuits are like silver bead-chains, like those little chains which attach the pens to desks in old-school banks. (Growing up I always played with these when mom was in the teller line. Do those ...

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I agree with what John Rennie said, "A photon doesn't interact with a single electron, it interacts with the entire molecule." The 'probabilistic process' is a better way of stating 'Give it a shot, and see what happens.' The probability between relaxing and splitting, or whether the photon and the molecule reacts at all, sounds good to me. Please ...

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When a molecule absorbs a photon it reaches to an excited state and there are various mechanisms in which the molecule can relax. Dissociation of the molecule is just one of the possibilities. It is not necessary to ionize (to separate the electron from) the molecule for dissociation to occur. What is necessary is to excite a bonding electron, that is, an ...

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This isn't really how it works. A photon doesn't interact with a single electron, it interacts with the entire molecule. Suppose you take the example of ozone photolysis to $O_2$ and an oxygen atom. We can do a calculation for ozone and come up with a series of molecular orbitals, then put two electrons in each orbital. So far so good. But if you remove an ...

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Electron degeneracy does not lead to an infinitely hard equation of state. The Pauli exclusion principle does not say that two fermions cannot occupy the same space; it says they cannot occupy the same quantum state. What this means is that as you squish the electrons together they have to occupy higher and higher momentum states. It is this non-zero ...

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If you read further on stellar evolution, if the mass of the original star is large enough electron degeneracy is overcome and the star becomes a neutron star, stable because of neutron degeneracy. This degeneracy is due to the Pauli exclusion principle which does not allow fermions of the same mass and charge to be in a single quantum state. What happens ...

1

It depends on what you want how you choose the polarization of the light. The polarization of your light determines the recoil of your electron and your ion. In photoelectron vmi you would like to see the angular distribution of how the electron detaches from the molecule, so you should select the polarization of your light such that the velocity vector of ...

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Use the equation E=hc/λ. In case you don't know, h is Planck's constant and λ is the wavelength in nano meters. convert electron volts to joules (E) using 1 electron volt = 1.60217662 × 10^-19 joules. Planck's constant is 6.62607004 × 10^-34 m2 kg / s

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Frequency of anything is infinitely variable up to the point of fusion. And then again Infinitely variable to to the next densest element order of matter. frequency of anything cannot be truly calculated as gravitational forces from its most central particle outward lowers in destiny Infinitely as well from one state of matter to the next. The best one can ...

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From the classical view there are electric and magnetic fields throughout space. And they have their own energy. And the energy in the fields changes as the fields change. And when there are charges the fields change differently there. They change in a way where energy flows from the fields into the charges where the electric field points the same ...

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It might not take a particular path at all. Some transitions might be strongly forbidden based on the difference of angular momentum of the states. But you can also have double photon transitions directly between two states, or have multiple transitions that have the final state of one transition be the starting state of the other. And if you take that ...

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Electrons move because they are in a region of space with a non-zero electric field. They don't accelerate to high speed in a wire because they keep bumping into things; a kind of friction which dissipates energy much like the friction you are used to that explains why resistors get hot. In effect their speed depends on the strength of the local electric ...

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'Path' is perhaps a misleading word to use here. Path typically means a physical path through space - a trajectory. You can use path in the context of a path through a sequence of energy states, talking about which energy states an electron is in in which order, but you have to establish the context to use the word like that before hand. Back to the actual ...

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In its rest frame an electron is always equal parts left- and right-handed chirality.

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As long as you provide a power source to a circuit, whether it is closed or not, electrons will definitely begin to move to a small amount. There are two specific cases which I think would best demonstrate this point. Case 1: A circuit with a capacitor. A simple capacitor contains two electrically conducting plates separated by an insulator, which could ...

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The electrons from the battery are not in the ends of the wires, no. The wires do contain electrons, however. Conductors have free electrons which can "float" around in the metal. There is an electric field between the two terminals of the battery. The electrons experience a force due to this field. When the wire is not connected, the electrons don't go ...

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I was told that electrons do not begin flowing unless the circuit is closed. This is true. Broadly speaking. The electrons from the battery are not in the ends of wire when it is open, The electrons involved in electric current are present throughout the metal wire. They are not supplied by the battery into an "empty" wire. The metal in the wire ...

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To answer in a more simple fashion: the electrons in the wires feel repulsion from the other electrons. When no current in moving around, they are in a state called equilibrium. Essentially, the electrons in front of and behind our electron - let's call him the "test electron" - are stationary, so he's roughly stationary too. The forces from his neighbors ...

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You are basically asking when current does happen. In a macroscopic level, the answer is simple: $$\mathbf J = \sigma\mathbf E$$ We can have this equation applied to a circuital point of view, thus arriving at Ohm's Law: $$V = RI,\quad\quad I = GV.$$ The value $R$ is known as resistance, and $G$ is known as conductance. When there is not current? ...

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The claim "Entangled electrons share the same quantum state" is not correct. In an entangled state there is no well-defined notion of the states of the individual components, this is the very definition of an entangled state: A composite state $\chi\in\mathcal{H}_1\otimes\mathcal{H}_2$ is called entangled, if it cannot be written as $\chi=\psi\otimes\phi$ ...

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Due to the chemical potential in the battery incitating charges to migrate, one battery end somehow suck electrons, yielding some "tension" of free electrons in the wire (slight loss in electrons). The other end somehow push, yielding some "pression" of free electrons in the wire (slight excess in electrons). If both ends are not connected because the ...

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