# Tag Info

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I assume your question was asked with the implicit "and everything else is kept the same" (still GR + standard model, just with one parameter tweaked). This would have a large effect, because now the neutron would be much more stable! The neutron is already quite stable (~ 10 minute half life), due to the tight energy constraints in the reaction decaying ...

4

Javier, brings up some interesting points. However, protons and neutrons get most their mass from relativistic quarks. If the quarks could be slowed down they would weigh a few electron masses. So what ever is responsible for giving the electrons mass its value seems to be giving the quarks their rest mass. I just checked the up and down,they are around 4 ...

3

In order for a current to flow steadily, you have to connect the conductor (copper in your case) to positive and negative poles of a battery. Then the electrons go from the copper to the positive pole of the battery - but - they are replaced by the electrons which come from the negative pole of the battery. Thus, the free electrons in copper are only needed ...

2

What are phonons? Phonons aren't particles like electrons or protons are, phonons are quasi particles, these type of particles are just used to describe excitations of a field: in phonons case, phonons are used to describe elementary lattice vibrations which have certain frequency. Electron-Phonon Interaction: Basically Cooper pairs are just pairs of ...

2

Note that Sommerfeld's model simply generalizes Drude's theory of metals by taking into account the fact that electrons are fermions, so Pauli exclusion becomes a very important factor. In Sommerfeld's model, there's no effective mass to talk about, as one basically ignores the atoms(nuclei) in the system and considers free moving fermions. So there, your ...

2

The electrons in a metal can be described surprisingly well as a gas of free electrons. So let me rephrase your question as: If I take a container with a gas in and rapidly partition it into two, will the pressure be the same on both side? If we look at a gas on the atomic scale it's a mass of atoms/molecules whizzing around at random. So on the large ...

2

Maybe a beginning of answer to your question could be found in Lindhard theory. Considere a fermionic field $$\Psi(\textbf{x},t)=\frac{1}{\Omega}\sum_{\textbf{k}_1,\textbf{k}_2}e^{\mathrm{i}(\textbf{k}_\alpha-\textbf{k}_\beta)\cdot\textbf{x}+\mathrm{i}(E_{\textbf{k}_\alpha}-E_{\textbf{k}_\beta})t/\hbar}a_{\textbf{k}_\alpha}^\dagger a_{\textbf{k}_\beta}$$ ...

2

The electron does not move - it has no well-defined position in the orbital state, and hence no well-defined momentum. Neither does it "teleport" around - as long as it is not interacting with something that forces it to be at a definite position, its state is "smeared" all over the electron as an electron cloud. Yes, this is essentially the Bohr model, ...

2

When a charged particle comes into the vicinity of another, it's path is deflected. It decelerates in one direction, and accelerates in another. All charged particles that are accelerated/decelerated by another charged particle, or a magnetic field, emit radiation. See: Bremsstrahlung. Synchrotron radiation. Cyclotron radiation.

1

The change in velocity of the electron give rise to emission of X-rays. The electrons arrive at the anode with very high velocity and end up at thermal velocities - which must mean they slowed down. Both statements are therefore true.

1

The fast electrons slow down in the cathode, mostly due to interactions with atomic electrons. But hard X-rays are produced mostly due to deflection to large angles in the field of atomic nuclei. Roughly speaking, an atomic electron can stop the projectile electron in a head-on collision, but a nucleus can "reflect" the projectile back, so here the ...

1

Not at all. Space is expanding, as in space is constantly being added. Although space might be added between the electron and nucleus, that does not effect the atom to significant degree. Its like having an atom in flatland and turning the flatland into a ball. the atom is not going to know much of a difference. If the sphere is returned to flat land the ...

1

If you think about the infinite square well problem, the states with higher energy have higher momentum, (and also a higher velocity). However, it is better to think of the higher energy states as higher frequency standing waves. Because they have a higher frequency, the have to "travel faster", which is where the large velocity comes from in the Fermi ...

1

In a Fermi-Dirac distribution, the relationship between temperature and the speed of particles is not intuitive. Even at cold temperatures, fermions can have high speeds simply because of degeneracy - the lower momentum states "fill up", leaving only states with large momentum available, and this is true even at very cold temperatures. However, the heat ...

1

To start with the electric field of the electron is as far as possible to measure symmetric, the electric dipole moment is very small. In this article The electron's EDM must be collinear with the direction of the electron's magnetic moment (spin). Within the standard model of elementary particle physics, such a dipole is predicted to be non-zero but ...

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The frequencies are the same but they are 180 degrees out of phase with each other.

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Given two like charges -- two electrons for example -- does moving them farther apart release a photon? Photons are released when charged particles are accelerated. . Moving them apart may generate photons if there is acceleration. If the velocity is constant, no radiation. Electrons in conduction bands of metals are in a quantum mechanical state and ...

1

Your instincts are spot on. While it’s still common for people to refer to electricity and magnetism as different phenomena, they’ve been formally unified since Maxwell’s 1873 paper on the subject, and they were known to be intimately related for decades before that through Faraday’s work among others. “Electromagnetism” covers all of the behavior of ...

1

In presence of external electric fields, If you cut it fast enough (at a speed faster than the conduction speed, you can have the two alved ending up with different charges. This is because the external field redistributes the charges on the conductor' surface to annulate the field there. so the charges will not be uniformly distributed. In absence of ...

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