Electron's magnetic moment in plasma/fusion physics?

Discuss how polywell fusion works; share theoretical questions and answers.

Moderators: tonybarry, MSimon

D Tibbets
Posts: 2775
Joined: Thu Jun 26, 2008 6:52 am
[phpBB Debug] PHP Warning: in file [ROOT]/vendor/twig/twig/lib/Twig/Extension/Core.php on line 1236: count(): Parameter must be an array or an object that implements Countable

Re:

Postby D Tibbets » Tue Jan 10, 2017 7:03 pm

To error is human... and I'm very human.

D Tibbets
Posts: 2775
Joined: Thu Jun 26, 2008 6:52 am
[phpBB Debug] PHP Warning: in file [ROOT]/vendor/twig/twig/lib/Twig/Extension/Core.php on line 1236: count(): Parameter must be an array or an object that implements Countable

Re: Electron's magnetic moment in plasma/fusion physics?

Postby D Tibbets » Tue Jan 10, 2017 7:15 pm

Concerning tritium in lava. The claim may have merit, but again take nothing at face value. A brief search turned up this article about vented steam from magma. It is actually from nuclear bomb testing- atmospheric water that has rained down and then been converted to steam from the heat of the magma.

https://hvo.wr.usgs.gov/volcanowatch/ar ... 04_20.html

Dan Tibbets
To error is human... and I'm very human.

jarek
Posts: 27
Joined: Wed May 25, 2011 2:33 pm
Contact:

Re: Electron's magnetic moment in plasma/fusion physics?

Postby jarek » Wed Jan 11, 2017 12:09 pm

First of all, let me remind why electron's magnetic dipole moment seems important from the point of view of fusion - I think the most crucial are back-scattering (on nucleus) type of electron trajectories due to the resulting Lorentz force, like (from simulation):

Image

If you imagine that there is another proton approaching from the direction of this trajectory, electron can remain between the two nuclei, screening the Coulomb barrier and finally leading e.g. to p-e-p fusion into deuteron.

This is kind of nonstandard ("dual") Lorenz force: for magnetic dipole (electron) traveling in electric field (of nucleus) - one of many EM dualities ( https://en.wikipedia.org/wiki/Duality_( ... _magnetism) ).
It would have exactly the opposite sign if the nucleus would be the magnetic dipole (in fact it is, but thousand times weaker).
To see it, for a moment make a boost so that electron stays and nucleus travels - in magnetic field of electron's magnetic moment, so Lorentz force acts on the proton ... but due to 3rd Newton law opposite force acts on the electron.
Here is a more formal derivation:
Image

I have managed to contact Eganova, but only got materials in Russian and couldn't find the details for the claims from the citation above.
The big problem with Sun is that it is believed that the core has only ~15MK, what gives ~1.4keV thermal energy per dof ... while for fusion we need to take e.g. protons to ~1fm, what needs >1MeV energy ... the temperature is thousand times too low.
The standard Gamov's explanation is quantum tunneling, but this is kind of magical explanation: proton teleports through energy barrier ... electron's assistance might bring a nonmagical understanding: help of electron maintaining trajectory between two nuclei, screening the Coulomb barrier and so making fusion much more probable - this "molecular fusion" of Gryzinski and Eganova, where dependence on temperature is far more nontrivial: such electron trajectories need stability, made more difficult while increasing temperature.

Regarding arguments for fusion inside our planet, the strongest I have seen concern tritium production in volcanoes - it quickly decays to He3 and amount produced in fission is nearly negligible - some volcanoes produce like 10000x more tritium than standard ways could explain:
http://lenr-canr.org/acrobat/JonesSEgeofusiona.pdf
Also, in some rocks there are found helium concentration up to 7% ( https://en.wikipedia.org/wiki/Helium ) - could you imagine getting such concentrations from alpha decay only?

ps. nice animation about 1-10 electron atoms in free-fall atomic model: https://www.youtube.com/watch?v=P2IsIkSn5bk
my slides: https://dl.dropboxusercontent.com/u/124 ... efall2.pdf
Gryzinski's papers (3000+ citations): https://scholar.google.pl/scholar?hl=en&q=gryzinski

D Tibbets
Posts: 2775
Joined: Thu Jun 26, 2008 6:52 am
[phpBB Debug] PHP Warning: in file [ROOT]/vendor/twig/twig/lib/Twig/Extension/Core.php on line 1236: count(): Parameter must be an array or an object that implements Countable

Re: Electron's magnetic moment in plasma/fusion physics?

Postby D Tibbets » Thu Jan 12, 2017 4:28 am

The electron interaction with the proton is certainaly significant but tiny in terms of electromagnetic shielding between two protons. My understanding is that this is because of the relative distances involved. A proton needs to approach another nucleon -proton in this case to such close distances that the mutual repulsion due to electromagnetic interactions is huge. This repulsion may approach ~ one percent of the strong interaction (which of course only becomes dominate when the protons are less than ~ 4 proton diameters separation because the carrier of the strong force can only travel about this distance before decaying). For an electron to shield against the mutual proton repulsion it has to be at a closer distance . This is apparently a rare event in most situations. Keep in mind that the electron is prevented from being in the immediate vicinity of a proton due to quantum mechanics . It can shield the incoming proton for a bit and this may decrease the distance that the incoming proton has to decelerate. This may effect the fusion probabilities to some extent and is figured into the fusion cross section curves. In cold matter (atoms) some heavy elements have orbitals that may actually penitrate the nuclear volume. Yet these elements do not fuse easily. Again, keep in mind that as Z increases, the number of protons increase and the electromagnetic repulsion against any test proton increases as a function of the sum of individual proton contributions. Increased electrons does not necessarily imply less proton repulsion from a nucleus. It is complex.

Having said all of this there are nuclear reactions where electrons are actually absorbed with a proton - so called reverse beta decay. This is the first step in P-P fusion in a star- and is why it is such an unlikely event. The cross section is about 10^20 times smaller than typical D-D cross sections.

Also consider Muons. They are "electrons" with about 40 times the mass. Quantum mechanics permits much closer approaches to nuclei/ protons and the resultant shielding can considerably increase fusion probabilities. Here the problem is not fusion probability but the harvesting/ production and management of the Muons. They just breakdown too fast.

And finally, consider our existence. If some of of the proposed interactions actually occur, then we probably would not exist. Unless you can explain how to work around the effects, the universe would be a much different place.

Dan Tibbets
To error is human... and I'm very human.

jarek
Posts: 27
Joined: Wed May 25, 2011 2:33 pm
Contact:

Re: Electron's magnetic moment in plasma/fusion physics?

Postby jarek » Thu Jan 12, 2017 7:11 pm

Regarding electron screening, imagine p-e-p initial symmetric situation - Coulomb force says that proton is four times stronger attracted by electron than repulsed by the second proton.
It seems initial symmetric p-e-p situation should collapse (into deuteron) - just like that.

However, the standard counterargument is quantum mechanics - that this electron becomes a relatively huge (10^-10m) probability cloud - which has no chance to remain between the two protons to screen their repulsion during the most crucial phase of the fusion (pm -> fm distance).
From the other side, electron's unitary charge is believed to be indivisible, its size is experimentally bounded e.g. by 10^-22m in Penning trap ( https://en.wikipedia.org/wiki/Electron# ... properties ).

So the real question is if quantum probability cloud is:
- fundamental - the indivisible elementary charge is objectively smeared into a huge volume, or
- effective - as in other probabilistic models, probability cloud only describes some average, or our incomplete knowledge.

While there are e.g. 10^-22m experimental boundaries for electron's charge, is there a single experimental evidence that it can be objectively smeared into a huge quantum cloud?

My road to realizing that the probability cloud is only an effective description has started with Maximal Entropy Random Walk (MERW) about 2008 - choosing the safest possible random walk: the maximizing entropy way.
The standard way, leading e.g. to Brownian motion in continuous limit, turns out to only approximate this entropy maximization in inhomogeneous space (like proton vicinity).
Doing it right by MERW turns out to lead to exactly the quantum ground state probability distribution: squares of coordinates of the dominant eigenfunction/vector of Hamiltonian - the quantum probability cloud appears just naturally if doing thermodynamics right, also for point entities.
our PRL paper: http://journals.aps.org/prl/abstract/10 ... 102.160602
slides: https://dl.dropboxusercontent.com/u/124 ... sem_UJ.pdf
my PhD thesis: http://www.fais.uj.edu.pl/documents/416 ... 74256fd065
Conductance simulator: http://demonstrations.wolfram.com/Elect ... ndomWalks/
diagram with example of evolution for defected lattice (there are self-loop in all vertices but squares):
Image

Agreeing that quantum probability cloud is only our effective description - that objectively electron's charge remains indivisible, there appears these trajectories remaining between the two nuclei - making fusion much more reasonable.
... but not simple - still the probability is tiny, requires some small space of initial parameters - electron's assistance only increases the chance from practically impossible to statistically noneligible.

update - Wikipedia article about MERW: https://en.wikipedia.org/wiki/Maximal_E ... andom_Walk


[phpBB Debug] PHP Warning: in file [ROOT]/vendor/twig/twig/lib/Twig/Extension/Core.php on line 1236: count(): Parameter must be an array or an object that implements Countable

Return to “Theory”

Who is online

Users browsing this forum: No registered users and 1 guest