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Everything posted by Bob_for_short
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So we arrive to the conclusion that we cannot, despite a huge number of textbooks, give an answer to the question in the frame of virtual particles. On the other hand, there is the Coulomb gauge where the Coulomb potential is clearly written. It leads to bound states an other obvious effects. That is why I have given my answer in terms of potential energy terms.
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There is no need to go outside the perturbation theory. Just fulfil the calculation to the end or make transition to the configurational space. You will obtain 1/r + magnetic terms from your propagator. That's the force terms.
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But: Also: Why to fool a poor guy? The "internal propagator" is reduced to the Coulomb and megnetic interactions in most of cases. This is more comprehensible.
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Just as a footbol gamer "absorbs" a ball: it acquires additional energy and momentum with it.
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There is no virtual particles and their absorption. But there are a Coulomb and magnetic interactions that we feel as forces.
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In the inertial reference frame where there is no acceleration a charged particle or dipole will not radiate. Falling down or rotating will cause EM radiation.
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Richard Feynman Quotes that surprised me....
Bob_for_short replied to dr.syntax's topic in Quantum Theory
I think everybody understands QM: the wave function that describes an ensemble of measurements. The problem is in a false impression that these multiple measurements are only necessary in QM and not in CM. This is a huge drawback of educational methodology. I would say: "Nobody understands Classical Mechanics", in particular where determinism comes from. It comes from averaging many measurements.- 8 replies
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So they are just long magnetic dipoles, as usual. Any long coil can be seen as a monopole at one of its ends.
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I think it will be a scalar temperature field T(r,t). Sometimes, if the electron and ion subsystems are not in "good" contact, they may have different Te anf Ti. But any temperature is a scalar.
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It only appears but does not disappears. Mathematically it means the propability to find a particle behind a barier is a growing function of time.
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Particle Physics - it matters
Bob_for_short replied to Severian's topic in Modern and Theoretical Physics
I did not read everything. You can add that the particle theory development is still in progress since the elementary particles are not really elemenatry but strongly interacting (sticky) and there are lots of pacthes and patches of patches that need to be replaced with something more compact and rational. -
Zero point fluctuations and the Casimir effect
Bob_for_short replied to Chuck Norris's topic in Quantum Theory
So why to insist on a misleading one? -
Zero point fluctuations and the Casimir effect
Bob_for_short replied to Chuck Norris's topic in Quantum Theory
If you do not believe me, read this: http://arxiv.org/abs/hep-th/0503158 -
It is a gravity force from, say, Sun.
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Richard Feynman Quotes that surprised me....
Bob_for_short replied to dr.syntax's topic in Quantum Theory
Add: "Nobody understands QM but me", and I will vote for it. Do not worry about POLL position - it is right. All we need is to read your post and vote. Comments can wait. -
Consider two interacting bodies. The Newton equations read: M1*a1 = F12 M2*a2 = F21 = -F12 So the action and reaction appear in different equations. The firs body feels only the force from the other. The other feels the force from the former. The third Newton law says these forces are equal and opposite. Now, any force makes a body move according to the Newton equation. The timing is obtained from it.
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Fortunately not, otherwise we would easily obtain a neutral system of a zero size (not atoms) so all atoms constituing us would collapse to give away their energy to somebody who would easily collapse itself.
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Zero point fluctuations and the Casimir effect
Bob_for_short replied to Chuck Norris's topic in Quantum Theory
The point is simple: the Casimir effect is an interaction of (neurtalized) real charges of plates. This interaction exists whatever material is used. -
Zero point fluctuations and the Casimir effect
Bob_for_short replied to Chuck Norris's topic in Quantum Theory
The boundary conditions with perfect conductors are only possible due to strong coupling the quantized EMF with lots of free electrons (free in your case). It is sufficient to replace the box wall with a non-metallic material and you will obtain a "black body" cavity - with a continuous EMF spectrum. The interieur vacuum remains a vacuum. -
The quantum oscillator of a given frequency ω is characterized with polarization e, direction k, and the number of its exited state n. So the photon population of a given mode is N(k, e, t). The equations for N(t) contain the external wave with its own direction, say, k' and polarization e'. The resonance conditions occur for k = k', e = e'. This mode gets enriched due to forced or stimulated conditions, the other modes (k ≠ k', e ≠ e') get depleted (with respect to the spontaneus radiation regime populations).
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Zero point fluctuations and the Casimir effect
Bob_for_short replied to Chuck Norris's topic in Quantum Theory
How one can excite the quantized electromagnetic filed oscillators? How photons are produced? By acting on a charge, pushing a charge. So the charge is like a particle in a couple of two-particle system bound with an elastic spring: External force =>OwwwwwwwwwwO, and the oscillator describes the relative motion of the couple (a quasi-particle with a reduced mass). So, the quatized EMF is always "coupled" to charges, they come together - it follows from the exact equations of QED. Electronium or a real charge is name of it - it contains both the charge and the quantized EMF. Interaction of plates affected with the quantized EMF is an interaction of real charges of plates at long distances. When electrically neutralized plates still interact due to presence of the quantized EMF in real charges. Even when non-neutralized (electron and proton in Hydrogen, for example), the quantized EMF gives corrections to the potential energy anyway - the Lamb shift. -
Zero point fluctuations and the Casimir effect
Bob_for_short replied to Chuck Norris's topic in Quantum Theory
"In vacuum" and "in a box" are different things. Perfect conductors mean a strong interaction with walls, so you cannot get rid of charges. My electronium is as natural as your box with perfect conductors. The sense of electromagnetic field is to get into the dynamic equations for charges as an external field. An external field has its own source. For example, the waves in a box are proper to this box. Same for electronium. Separation of electron and of quantized EMF does not mean they are non-interacting, independent systems but subsystems of one compound system belonging to separated variables, like R and r in a two-body system. Then no questions arise about Casimir, Lamb, and other effects. -
Zero point fluctuations and the Casimir effect
Bob_for_short replied to Chuck Norris's topic in Quantum Theory
About fluctuations, I can tell that in an atom there is always an electron coupled to a nucleus. The natural variables are the center of inertia (CI) and relative coordinates. The total wave function of such a compound system is a product of a CI plane wave and an atomic wave functions: Ψ = exp(-iPR/ћ)⋅ψ(r). The atomic ground state can be considered as the vacuum (no excitations). The same is valid for quantum oscillators and charges - they come together and represent zero-mode oscillations in compound systems. An electron with its quantum oscillators (I call it an "electronium") can be described quantum mechanically in full analogy with an atom: as a product of the CI and relative motion wave functions (the oscillators). So there is no photons in the ground state of such compound system. Charge is smeared quantum mechanically in compound systems, for example, in atoms there are negative and positive charge clouds of different sizes around the atomic CI (described with atomic form-factors). Similarly in the electronium the electron charge is smeared but no photons exist in the ground states. Real photons are excited states of electronium. -
Zero point fluctuations and the Casimir effect
Bob_for_short replied to Chuck Norris's topic in Quantum Theory
They modify because of interaction. The filed itself does not exist, don't you see?