[Widdekind]

I understand, that "while decoherence typically happens very swiftly, it is not quite instantaneous" (dickau); and, that "decoherence" and wave-function "collapse" occur, in chemical reactions:

Quote

When a chemical reaction takes place, one substance suddenly changes into another — an abrupt change described by a nonlinear equation. Our perception of abruptness depends on the timescale we use to observe these processes. If we analyzed one of the seemingly instantaneous chemical processes in slow motion, we would see a gradual transformation, as if we were watching a pat of butter melting in the sun. When the process is viewed frame by frame, the changes are not abrupt" (J.M.Rubi, Long Arm of the 2nd Law (Sci-Am Nov 2008)).

If so, then the "contractive collapse", of the quantum 'particle' "field" -- cp. "Erwin Schrodinger thought that the quantum state of a particle -- in the form of its wave-function -- was a real field, as a classical electro-magnetic field is real" (mermin) -- occurs "quickly" but not "instantly" ??

[Widdekind]

Reportedly, "entangelment" decoheres "gradually", as interactions with the environment "whittle away" at the entanglement relationship:

Quote

In their recent study, these physicists exposed four entangled ions to a noisy environment...

"At the beginning the ions showed very strong connections," says Julio Barreiro. "When exposed to the disturbing environment, the ions started a journey to the classical world. In this journey, their entanglement showed a variety of flavors or properties." Their results go far beyond what was previously investigated with two entangled particles since four particles can be connected in many more ways. This investigation forms an important basis for the understanding of entanglement under the presence of the disturbances of the environment and the boundary between the dissimilar quantum and classical worlds.

[Widdekind]

B.R.Martin's Particle Physics; and K.Ford's 101 Quantum Questions; give me the impression, that "wave-function collapse" is spontaneous, when exo-thermic, in a manner akin to chemistry, i.e. "chemical reactions are QM wave-function collapses". Vaguely, wave-functions, of quantum particles, are spatially extended; and so, quantum particles "feel" a "variety" of potential energies, as they "reach out" through space. And meanwhile, wave-functions have "multiple personalities", some of which have higher momenta-and-energies; whilst others have lower momenta-and-energies. And, in regions of space, where the particle's local energy, is less than the local potential, there the WF decays away. Conversely, in regions of space, where the particle's local energy, is higher than the local potential, there the WF is reinforced. In such a way, the energy environment, of a particle's WF, can "cultivate" that WF, demoting the WF in some regions, whilst promoting it in others -- so that WF "collapse" is, at sufficient time resolution, a gradual process of "pruning & cultivating" the WF. Physically analogous to chemical reactions, spontaneous wave-function "collapses" are "driven" by energy, i.e. when one "personality" of the wave-function finds an energetically advantageous "fit", that "persona" is gradually-but-quickly spontaneously "promoted" -- perhaps as, somehow, energy is transferred into the "promotion" of virtual force carriers, per G.Zukav's Dancing Wu Li Masters ??

[Widdekind]

Please ponder an electron, propagating towards a proton. Now, "before the electron reaches the proton", the electron's incident wave-function will not appreciably over-lap, with any of the potentially available bound hydrogenic states. And "after the electron has been there and gone", the electron's scattered wave-function will not appreciably over-lap, with any of those bound states, either. However, "in between", when the wave-function of the electron has "enveloped" the proton, i.e. as the electron is "on top of" the proton; then the over-lap integrals will be non-zero.

To make an investment analogy, each available bound H state, could be likened, to a "stock". And, the spectrum, of available bound H states, could be likened, to a "portfolio of stocks". Now, as the electron impinges upon the proton, the "stocks" in its "portfolio" will, at first, "rise in value". Then, as the electron scatters away from the proton, those "stocks" will "fall in value".

Is it not true, that the electron does not directly "perceive" the proton, but only the "virtual photons" emanated by the proton, i.e. the proton's electrical potential well ?? And so, is it not true, that the electron's only possible "perception", of its "interaction", with the proton, would be its "stock values", in its "investment portfolio" ?? And so, are not those "stock values", qualitatively visualized, in the following figure, the only possible information, which could possibly "trigger" a wave-function "collapse", of the electron, into some captured, bound, H state, i.e. a QM detection / measurement / observation ?? If so, then something, seemingly, must happen, between "the stocks are all making money", and "the stocks are all losing money", to trigger the "selling off of some stocks", and the "buying more of (one) other stock" ??

I want to ask, if wave-function "collapse" is, ultimately, a smooth & gradual process, via which a wave-function is "con-formed" into a "desired shape"; then would that immediately imply, that the "collapse" process, involves a "positive feedback" process, via which the electron (say) "perceives an error", between its current wave-function; and a "desired" bound H (say) wave-function ?? I want to ask, what other known physical process, besides feed-back control, can "conform" things, into "desired" homeostases ?? Would not the electron (say) need to "perceive" the "wave-function discrepancy" , as some sort of "phantom potential" in the SWE, which "drives" the electron into the "desired" distribution, i.e. "shoves the electron into shape" ?? Perhaps there are published articles, detailing such scenarios ??

[juanrga]

Widdekind, on 29 January 2012 - 09:32 PM, said:

I understand, that "while decoherence typically happens very swiftly, it is not quite instantaneous" (dickau); and, that "decoherence" and wave-function "collapse" occur, in chemical reactions:


If so, then the "contractive collapse", of the quantum 'particle' "field" -- cp. "Erwin Schrodinger thought that the quantum state of a particle -- in the form of its wave-function -- was a real field, as a classical electro-magnetic field is real" (mermin) -- occurs "quickly" but not "instantly" ??

Yes, it takes some time. The time scale is given in dynamical models of collapse.