Quantum fluctuations and randomness

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Quantum fluctuations and randomness

Postby hyksos on August 12th, 2017, 4:58 pm 

While this was mentioned in another thread about determinism, after some thought, I have decided that this topic is crazy enough, and interesting enough to warrant its own thread.

Itinerary

This is what I hope to accomplish in this thread.

  • Give the reader a visualization of why the quantum behavior of electrons would manifest itself as fluctuations in the ground state of a solid.
  • Give the reader an understanding of why quantum behavior would result in a persistent "wiggling" of molecular structure.
  • Post examples of experiments performed in real labs, where this "quantum fluctuating" was actually observed in a very real way.
Last edited by hyksos on August 12th, 2017, 6:14 pm, edited 1 time in total.
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Re: Quantum fluctuations and randomness

Postby hyksos on August 12th, 2017, 6:10 pm 

For the impatient reader who does not want to slog through the pedagogical diagrams and my long-winded escapades, here are fast-lane links to this topic.

https://en.wikipedia.org/wiki/Quantum_phase_transition

https://en.wikipedia.org/wiki/Quantum_critical_point

Okay lets begin.

The basic overview of what I am going to describe here goes as follows. We expect that if we take a crystaline solid (usually a conducting metal) and cool its temperature down near absolute zero, we remove all the thermal shaking from the molecules due to classical heat. However, we expect that some residual temperature will still persist in the solid, even after we have removed all thermal energy from it completely. This residual "temperature"/"shaking" that persists in the solid, we will call these Ground State Quantum Fluctuations , or quantum fluctuations for short.

{ Note to moderators : This is not a personal theory. These quantum fluctuations have been observed in real laboratory settings. Sit tight, and I will give citations to all of them in due time-- right in this thread. }

To get us there, I will start with some facts about reality, stated as axioms not to be debated in this thread :

1.) Electrons are not little blue charged spheres that zip around in the void. Instead, electrons manifest in spacetime, disappear, and re-appear somewheres else in spacetime. Where they appear next is determined only probabilistically by the Schroedinger Equation.

2.) The very teleportating nature of electrons is the reason why chemical bonds form between atoms. If electrons did not act like this, molecules would never form. (this topic is more subtle and difficult than stated here, but I'm short on time so We will gloss it)

3.) The most precise method of measuring temperature in supercold settings is to measure the magnetic field produced by ferromagnet solids. The electrons in a ferromagnet respond to heat and cold by lining up their spins while cold, and dis-alligning their spins when warmed. The degree in which all the electrons are "pointing the same direction" determines the strength of the magnetic field produced by that solid. This process is exactly what happens in a magnet attached to your refrigerator.

The reader will need to visualize a lattice of atomic nuclei, surrounded by a ghostly blur of an "electron cloud". In the cloud, the electrons appear and disappear at will, appearing more oftenly where the schroedinger wave is strong, and less oftenly where it is weak. When the electron does appear, its presence will tug on the nearby nucleus of the bound atoms in the solid. (the 'tugging' is just classical charge forces). We expect that as the electrons flash in-and-out of existence, that the tugs will be applied in a stepwise manner to the nuclei nearby, once in that direction, once again in another direction.

We declare that this random tugging is actually random and uncaused in direction. We suppose also that this random tugging is intrinsic at an ontological level. Therefore our theory predicts that the random electron tugging will persist even when all thermal energy has been removed from our solid. In the literature, the eagle-eyed reader will see the same reasoning spelled out-- and often the writer will describe this tugging as being random "...because of the Heisenberg Uncertainty Principle."

QPT_t0.png

..
QPT_t1.png



Meanwhile, back in the laboratory, atoms are very very small. An actual solid should exhibit some kind of bizarre, residual heat that persists in the sample, well after removing all the thermal energy. Of course, we can never actually get the sample to exactly zero kelvin. That's okay though, we need only cool the solid to some nanokelvin temperature that is below the wiggling level of the quantum fluctuations.

Okay that's all nice and neat theorizing. Cool story, bruh. But has this actually been done?

Yes.

In the next post we get real. I will enumerate all the instances where this has been done in a lab with real solids, who will be given by name. Citations will be provided.
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Re: Quantum fluctuations and randomness

Postby DragonFly on August 12th, 2017, 6:15 pm 

Anton Zeilinger claims to show quantum randomness to the three or four sigma level, he providing the great saying of "Randomness is the bedrock of reality".

To me, it seems that at the bottommost, fundamental, bedrock level that if there isn't/can't be anything beneath/beyond telling things what to do then 'random' may have to happen, that is, there are outputs without inputs; but I still have to wonder why some specific random action went next instead of it happening later or elsewhere. Or else what happens next is a result of the whole system.

It also appears that either there has to be wiggling, that is, stillness is impossible, or that absolute zero can't be gotten to.

(I still have to read your latest post which is clashing here now.)
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Re: Quantum fluctuations and randomness

Postby hyksos on August 12th, 2017, 6:43 pm 

In almost all the experiments mentioned below, the solid compounds are chosen because they exhibit very strong electron/electron interactions, and not necessarily the nuclear tugging mentioned above. At very low temperatures, the electron clouds begin to act like a liquid phase, because the electron/electron interactions are as strong as those interactions seen between water molecules in liquid water. "viscous flow" is exhibited by electrons in these semiconductors.

In any case, the magnetic fields undergo a transition, which cannot be explained by thermal heat. What is changing then? The answer is the quantum interactions of the electrons is changing. In some publications, the authors don't really understand what they are measuring. They write that the inexplicable data is due to "exotic quantum states".

(1)
Bose-Einstein Condensation of a spin-magnetic compound TlCuCl3 (Thallium Copper Chloride)
https://homepages.dias.ie/dorlas/Copies/Magnon-BEC.pdf

(2)
Quantum Phase Transition observed in pressure-induced method. TlCuCl3 (Thallium Copper Chloride)
https://journals.aps.org/prb/abstract/10.1103/PhysRevB.69.054423

(3)
Quantum Critical Point observed in LaCuO2.5 (Lanthanum Copper Oxide).
https://journals.aps.org/prb/abstract/10.1103/PhysRevB.56.8760

(4)
Quantum fluctuations account for the data seen in spin liquid phase of CuBr4 (Copper Bromine)
https://journals.aps.org/prb/abstract/10.1103/PhysRevB.79.020408

(5) further reading ,
http://brucenormand.weebly.com/quantum-phase-transitions.html
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