Posts by Jarek

Eric, Gamow tunneling is in 3D, see e.g. slide 15 here: http://www.tunl.duke.edu/nnpss/lectures/17/UNC_2011.pdf
I am currently reading "Nuclear physics of stars" book, but it will take some time.
For this moment, my only objection is that, in contrast to Boltzmann distribution, tunneling is kind of a magical explanation - especially for nuclei, which are usually modeled with classical trajectories. This is a compact object which cannot just teleport through a potential barrier - we need a concrete mechanism for that.
Indeed, in physicsforum there are cited papers that electron screening has minor effect - but they treat electron as probability cloud, which is great for dynamical equilibrium cases ... fusion is not.
My point here is that asking for electron trajectory (averaging over a relatively long time to this probability cloud), there are trajectories remaining between the collapsing nuclei - screening the Coulomb barrier.
That probability cloud is too blunt static tool for this subtle dynamical situation.

Regarding my question, Gamow tunneling still weakens exponentially with low temperature - fusion still needs millions of Kelvins.
If one believes in CF, tunneling is definitely not enough.
Moreover, if proposing a CF mechanism, it should require a condition which is present in 1000K, but not present inside stars - otherwise their energy production, evolution should be drastically different (maybe it is - are there any arguments?)
E.g. if one says 'hydrinos' or 'discrete breathers', he should also answer the question: why this explanation does not apply also to let say 100 000K region of the Sun?

An example of such explanation (applying to 1000K but not 1MK) is requirement of stabilizing electron trajectory for molecular bond between two nuclei - in million kelvins fusion requires smaller assistance of electrons, but it's more difficult for fast electrons to find a stable trajectory between nuclei for the short moment of approaching to collision.

Any other mechanisms which could grow in strength while lowering temperature?
Or maybe you have seen some alternative models of stars - with included LENR?

As energy production of most of stars seems well understood, they base on p+p, p+d fusion starting at a few million K by Gamow tunneling ... what are the responses of CF enthusiasts to the objection that fusion being still nonnegligible down to 1000K should dramatically change physics of stars?

Is there any other way of defense than trying to rely on requirement of stable molecular bonds? - for which one possibility is electron bouncing between them on nearly a line, screening the Coulomg barrier.

Let's try to ask it on physicsforums:
https://www.physicsforums.com/…ion-in-solar-core.889651/

Padam, could you elaborate?
Getting to 1pm distance is relatively simple, protons should get there all the time due to just thermal energy in 15MK core of the sun.
However, getting to 1fm so that nuclear force can start acting requires 1000x more energy (without electron remaining between them) - how is it explained?

Considering electrons, some could form low angular momentum orbit around one nucleus: ellipse deforming into nearly a segment in some direction. If another nucleus is approaching from this direction, this electron could stay between them, kind of bouncing between the two nuclei in a series of back-scatterings, screening the Coulomb barrier.

How can it be explained without such electron assistance? - how proton could get 1000x larger energy than thermal to cross the Coulomb barrier?
"Because tunneling" might be a good explanation for electron, but not for 2000x heavier proton - for which even mainstream consider trajectories and forces ...

ps. It's ever worse - just having energy for getting to 1fm distance (~1.4MeV, 1000x more than thermal in solar core) would solve the problem only in 1D.
In 3D you not only need this energy, but also have VELOCITY PERFECTLY POINTING THE SECOND NUCLEI - otherwise they will just bounce from the repulsion and fly away.

Eric, so please explain where proton gets 1000x larger energy than thermal - to get to ~fm distance required for fusion?

Thermal energy in solar core is 1.4keV, p + e -> n needs 782keVs.
So Boltzmann says their concentration should be ~exp(-782/1.4) ~ 10^-243.

Zephir, Eric - please just do the math.
Solar core is believed to have density 150g/cm^3 ( https://en.wikipedia.org/wiki/Solar_core ).
Assuming it's hydrogen only (N_A per gram), one can easily calculate radius of ball corresponding to every proton: I got I.38 * 10^-11m, what makes sense.
As electron concentration is the same, one can imagine analogous ball around every electron.

So free electrons would have there 10^-11m order of distance from the nearest proton.
Assume we want p - p fusion. Thermal energy of 15MK gives 1.4keV what allows to get to 10^-12m distance.
In this distance free electron is already 10x further than the target nucleus: Coulomb force is 100x smaller.

But 10^-12m is just the beginning - we need 1000x more energy to get to range 10^-15m of nuclear force ... and interaction with free electrons become completely negligible during this trip - their screening doesn't matter here!
The only way electron could really help here is having trajectory imprisoned between these two colliding nuclei.

Quote from Zephir_AWT

Under these extreme pressures the electrons will be pushed between protons again, i.e. their shielding effect would apply there more than inside the sparse plasmas.

Still you have e.g. 1 electron per proton - concentration of electrons increases proportionally to concentration of nuclei.
Maybe it could reduce average proton-electron distance let say from 100pm to 10pm ... while the most costly in fusion is going from e.g. 1pm to 1fm - where this screening from electron cloud becomes just negligible.

Again, the only option for non-negligible electron assistance is that there is a single electron remaining between the two colliding nuclei.

Nuclear force has range ~1fm ( https://en.wikipedia.org/wiki/Nuclear_force ) so for fusion we would need to take two protons to approximately this distance - Coulomb says that it would require ke *e*e/r ~ 1.4 MeV.
However, the temperature in the core of our sun is said to be 15 million Kelvins ( https://en.wikipedia.org/wiki/Solar_core ), what means only ~1.4 keV thermal energy - it is thousand times smaller than required to get nuclei to 1fm distance, could only get to 1pm distance.

How is it explained that it is sufficient for fusion? If just as "tunneling", it should be compatible with Boltzmann distribution - giving ~exp(-1000) ~ 10^-435 scale of probability.
Maybe it is already required to consider electron-assistance here: that there is electron remaining between the two collapsing nuclei?

Quote from Wyttenbach

As Jarek ( and many papers) pointed too: An external field (shaped electron "cloud") may be able to polarize the nucleus, this might slightly change/ (de-) polarize the internal trajectories of so called B-electrons, which are assumed to be "banging around" inside the nucleus.

I don't think electrons can "bang inside" a nucleus: while the largest diameter of nucleus is ~15fm, Lorentz force bends the trajectory of free-falling electron making the minimal distance ~100fm.
This distance is sufficient for nuclear forces e.g. to capture electron or give it some energy in internal conversion, but not to directly enter the nucleus.

Quote from Eric Walker

I think I see where you’re going with this now. According to QM, the degrees of freedom of a nucleus are quantized. The speed of rotation, the number and energy of any nuclear phonons, the potential energy latent in arrangements of nucleons above the ground state, etc., all correspond to distinct energy levels of the nucleus. This picture does not seem to leave open the possibility of a kind of white noise that perturbations from orbital electrons could build on top of in order to move a nucleus into a higher energy level through some kind of stochastic resonance. Perhaps zero point energy provides such a noise floor. This is not an area where I can speak from a position of knowledge.

The quantization corresponds to a discrete set of (dynamical) metastable states: local minima separated by energy barriers.
For atomic orbitals, like in Couder's picture, the quantized states correspond to resonance with the field to get a standing wave to avoid bremsstrahlung.
Changing the (dynamical equilibrium) state is rapid but not instant (e.g. delay in photoemission)

For nucleus I also believe that we can ask about dynamics hidden behind effective quantum description (expanding liquid drop model) - some dynamical structure of fields, with a complex landscape of local minima - states between which we observe as transitions.
The mainstream view is that we need some QFT to describe it - as there is a varying number of particles in this never-ending series of creations and annihilations of e.g. interaction bosons.
However, there is also an alternative way to describe a varying number of particles: classical field theory with solitons (nonlinear) - it also supports varying number of particles.
I believe there is a correspondence between classical FT with solitons and QFT - we could calculate effective parameters describing interactions of solitons and insert them into Feynman diagrams of perturbative QFT ... however, this is really hard to calculate.

Anyway, I imagine nucleus as a (dynamical) spatial structure of a field - I have some candidate (it explains e.g. why proton is lighter than neutron, deuteron than p+n: because baryon structure requires some positive charge (less than e) - neutron has to compensate it what is costly, in deuteron baryons share the positive charge), but I am not insisting on the details.
Transiting between its states is rapid (not instant) and due to Noether theorem it has to release the energy (and momentum and angular momentum) difference - as gamma.
It is really surprising that these photons cannot disperse - have to be localized (be soliton).
For optical photons my intuition for its reason is the angular momentum - they are created from changing spin of electron e.g. from -1/2 to +1/2: by rotation 180 deg.
This rotation creates photons as twisting wave like behind marine propeller - in contrast to water, they don't disperse because EM field has no viscosity.

For nucleus again the angular momentum might be what prevents this energy in EM field from dispersing.
But there might be nuclear processes without any twisting, like symmetric p-e-p collapse. This symmetry should be maintained for the EM wave carrying the energy difference - no angular momentum preventing photon from dispersing its energy.

Regarding experimental evidence - such EM impulse would convert this energy into thermal energy of surrounding atoms - it seems extremely difficult do directly detect.
So lots of LENR claims: with silent detectors but excess heat might be seen as such experimental evidence.

Regarding lack of gammas, you have written about 10MeVs - you would need a really long cascade of gammas (requiring semi-stable states of nucleus), electron of this scale from e.g. internal conversion would also be well seen, e.g. from bremsstrahlung gammas it would produce.

What do you think about releasing this energy in a form of a less localized form - gammas "maintain their shape" while traveling, so technically they are solitons of EM field.
Why this energy couldn't be released in a form of e.g. cylindrically-symmetric EM wave, like from line antenna - such wave would disperse this energy in 1/r way, converting it into local thermal energy.

Regarding me being "a fan of Gryzinski", it is much more complex. So much earlier (~2008) I was working on Maximal Entropy Random Walk (MERW, my physics PhD) - showing that thermally perturbed trajectories average to quantum probability distributions (MERW has started in my physics MSc alongside ANS coding your data is written with if you use Apple or Facebook).
MERW has also lead me to the question of the structure of particles (~2009), which should start with the question of charge quantization - it has a natural analogue in mathematics: topological charge. Using such picture for electron (started by Manfried Faber), a qualitatively trivial model (vector field with e.g. (||v||^2 - 1)^2 Higgs potential) recreates electrons as the simplest charges - with quantization, pair creation/annihilation, finite energy of charge (infinite for point charge), Coulomb force and the rest of electromagnetism. I have expanded it other particles and nuclei (slides, essay).

Anyway, we finally need concrete trajectories for these solitons/electrons ... which in time average to quantum statistics due to MERW - and I know only Gryzinski who has made a solid work here - basing on agreement with experiments, many on them. But I am open for other reasonable approaches (?)
His model doesn't cover the structure of nucleus (and he believed neutron was proton with electron, I disagree with) - I rather use intuitions from my model here, but only for this possibility of radiating energy as cylindrically-symmetric EM wave.

Regarding shocks from PHz electron passing in ~10^-13m distance, it doesn't transfer energy, just kicks the structure of nucleus, shake it to speed up finding energy minimum.
This nucleus can release abundant energy, what means it is in a local energy minimum, but there is a lower energy minimum behind a barrier.
A single kick from the passing electron is not sufficient to cross this energy barrier, but many of them can help crossing it (decay), like in stochastic resonance ( https://en.wikipedia.org/wiki/Stochastic_resonance ).

Regarding the webpage you cite ( http://math.ucr.edu/home/baez/…dNuclear/decay_rates.html ), it mainly discusses electron capture, but there is also:
"A 1996 paper discusses this bound-state decay of bare-nucleus
rhenium-187. Whereas neutral rhenium-187 has a half-life of 42 ×
10^9 years, the authors measured fully ionised rhenium-187 to have a half life
of just 33 years! They discuss the cosmological implications of the altered half
life of rhenium-187 in various degrees of ionisation in stellar interiors, and what that
implies for our knowledge of galactic ages."
which surprisingly has an opposite effect - the presence of electrons prevents from decay - I will have to think about it, but these kicks from passing electron could have also stabilizing effect e.g. through a resonance: decay may require change of the frequency, while the regular kicks can stabilize nucleus in a different frequency.

The lack of gammas is a big objection.
As for fusion, EM impulse might be the answer: that instead of releasing the energy as EM soliton (gamma), the EM wave could have a different shape, e.g. a cylindrically-symmetric shape like in line antenna, dispersing the energy with 1/r.
Or maybe nuclear processes could radiate energy in non-quantized portions, e.g. maintaining the power (released energy per second) for a longer time, instead or radiating it in nearly immediate steps (? spatial explanation seems more likely for me).

Regarding mechanism for indirect action of shell electron on the nucleus, these frequent (~petahertz) electric and magnetic shocks from electrons passing in ~10^-13m distance seem quite a shaking of the nucleus - might be crucial for rate of releasing abundant energy.

There is documented difference of rate for electron capture while ionizing the atom - are there more processes with observed such difference (nuclear process being affected by shell electrons) ?

I don't have experience with such unconvential fission, alpha, beta ... but their standard versions are well seen in detectors.
I understand it is not seen? What is experimental evidence of such events? Only excess heat?

Regarding electrons affecting nuclear processes, free-fall atomic model has an interesting third option: it says that electrons are passing in ~femtometer distance from nucleus, ~10^15 times per second.
Each such passing is a shock to the structure of nucleus from the huge electric and magnetic field of electron - such regular shocks might induce some internal process in nucleus, e.g. through stochastic resonance: https://en.m.wikipedia.org/wiki/Stochastic_resonance

Quote from Eric Walker

In the case of alpha decay/fission, there is in fact a Coulomb barrier that needs to be crossed, but from the other direction: the alpha particle must tunnel through the Coulomb barrier of the daughter nucleus, from the inside. The idea is that this process can be enhanced appreciably through electron screening. Alpha decay and fission are particularly sensitive to the width of the Coulomb barrier, and screening decreases that width and hence increases the tunneling rate.

These are just fission, alpha and beta decay - a natural tendency of some isotopes to spontaneously release energy ... these seem to be conventional nuclear energy sources?

By (screening) you mean that the presence of electron cloud affects the rate of these reactions?
In other words, ionization of atoms reduces the rate.
It is what they observe for electron capture: https://en.wikipedia.org/wiki/…_capture#Reaction_details
"The electron that is captured is one of the atom's own electrons, and not a new, incoming electron, as might be suggested by the way the above
reactions are written. Radioactive isotopes that decay by pure electron capture can be inhibited from radioactive decay if they are fully ionized ("stripped" is sometimes used to describe such ions). "

So one reason might be presence of electrons traveling very close to the nucleus.
A different reason can be indeed the screening - ionized atom is positive, attracting negatively charged particles.

So please give an example of sequence of LENR reactions which could lead to a practical energy source without: fusion, crossing the Coulomb barrier, or just using decay of some isotopes (used e.g. to power satellites) ?

Quote from Wyttenbach

The only thing what must be answered (hen egg problem): Is there first a current or the collapse or is it all together a well synchronized cascading event!

As we agree that QM describes dynamical equilibrium, which is not the case here - we need to ask about concrete trajectories of electron to understand hypothetical CF.
This trajectory is mainly affected by the Coulomb force - getting Kepler orbits in first approximation.
As we have discussed, there are many arguments that these are very low angular momentum Kepler orbits (e.g. electron capture, magnetic dipole moment of atom, Helbig-Everhart scattering resonances etc.) - these are ellipses degenerated into nearly lines coming from the nucleus.
There is some probability that another nucleus will be incoming from the direction of such very flat ellipse - if they are able to hold this electron during the collapse, they can get close enough for fusion.
Earlier, to avoid torque from spin-spin interaction, they should align their spins.

So this is a well synchronized three body event.

Quote from padam73

As Hagelstein rightly says, the challenge is more about explaining the lack of expected radiations than how to achieve fusion.

Their difficulty is hard to compare ... both crossing the Coulomb barrier and nearly lack of observed radiation needs to be explained, understood.

In earlier posts of this thread you can find my proposal to explain this lack of radiation, e.g. first post here: Electron-assisted fusion
So assuming CF if true, I believe we need e.g. p - e - p three body collapse: similar charge behavior like in linear antenna.
They should earlier align their spins, getting a system with cylindrical symmetry - maintaining this symmetry while the collapse, the released energy should have also a form of a cylindrically symmetric EM impulse.
The trick is instead of producing localized EM wave (gamma) - maintaining localized energy, release this energy in cylindrically-symmetric EM wave: which disperse this energy as 1/r - heating up a small neighborhood.

Here are some cylindrically-symmetric EM waves from linear antenna ( http://ocw.upm.es/teoria-de-la…nnas_athens09_tuesday.pdf ) :

Why the released energy has always to be produced as localized EM soliton (gamma)?
Why releasing this energy in cylindrically-symmetric collapse, the result cannot be such cylindrically-symmetric EM wave? ... solving the Hagelstein's problem.

Quote

QM-electron (probability-) clouds are only useful in statistical environments, i.e. systems near equilibrium conditions. The formalism was not invented to handle sudden multidimensional changes. (...) They call this short period just tunneling... (= lack of explanation...)

I completely agree here - QM describes dynamical equilibrium, we need a more suitable description for rapid changes - asking for the actual trajectory of electron.

I thought there is this large interest in LENR becouse of bringing hope for amazing power source ... where I think we agree that

1. We need fusion,
2. Which needs crossing the Coulomb barrier (going through neutrons is nonrealistic),
3. For which the only realistic explaination for being statistically non-negligible is electron staying between the two nuclei,
4. For electron staying between two nuclei down to femtometer scale we need to ask about its trajectory - quantum probability clouds are not sufficiently localized.

Do we agree here?

Eric, regarding me being fixed on electron remaining between the two nuclei as the only reasonable explanation for hypothetical fusion in 1000K, so we had 260 posts in this thread and I honestly haven't seen any other reasonable explanation here (?)
Chemistry, charge concentration, screening, topological defects etc. might be sufficient for taking two nuclei to picometer distance ... but fusion requires thousand times smaller distance, and so thousand times larger energy (V ~ 1/r).
This is just far beyond such "electron-cloud-related" explanations - it is a completely different energy scale.
If it's impossible for an electron to stay between the two nuclei, for this moment I don't see fusion in 1000K realistic - especially that it's hard to believe that nearly 30 years is not sufficient to get a single really clear demonstration.

Regarding effective asymptotic treatment of atom as effective multipole, this is only one of many ways that can be used to test models of atoms in various scattering experiments.
Scattering is nearly a direct way to ask nature about the structure of atom, and various scattering scenarios was the basic way for Gryzinski to infer and test his model - these his papers have >2000 citations: https://scholar.google.pl/scholar?hl=en&q=gryzinski

Ok, as the title says, I am focusing here on fusion. Other nuclear reactions have different issues, but the main goal and claims are LENR as amazing energy source - I cannot imagine without fusion and crossing the Coulomb barrier (?)

Quote from Eric Walker

To your point about the asymptotic screening of the nucleus on the part of bound electrons, this is an interesting and valuable observation. I’ll add to it that what presents a barrier to the breakup of a nucleus by fission or alpha decay is not the core nuclear charge, but the Coulomb barrier, which surrounds the nucleus like a sheath that extends some picometers out. Hence the suspicion it is there (outside of the nucleus) that screening would need to take place for breakup to occur.

We might take from your observation, however, the thought that perhaps beta decay processes, which require overlap of any electron charge with the nucleus itself (and not just the Coulomb barrier, outside of the nucleus) will be more likely with lighter nuclei unstable to beta decay/electron capture and less likely, all else being equal, with heavier nuclei.

The best way to experimentally test effective asymptotic view of atoms as electric multipoles (static + oscillating) is exactly through scattering with low energy electrons - they are charged and very light.
It was introduced not by me, but in Gryzinski's 1970 paper ( http://journals.aps.org/prl/ab…10.1103/PhysRevLett.24.45 , then extended in his 1975 papers) as classical explanation for Ramsauer effect, which was previously believed to be purely quantum ( https://en.wikipedia.org/wiki/…r%E2%80%93Townsend_effect )

However, this is only asymptotic behavior - while crossing from pico- to femto-meter distance, which is the most crucial during nuclear fusion, the electron cloud of a given atom becomes nearly negligible - the incoming particle feels practically only the charge of the nucleus ... unless there is electron staying between them.

To support that, I have cited the screening coefficients for shell electrons:
Z_eff = Z - s

As you can see - this screening quickly drops with the distance (shell number) from nucleus: for 1s orbital, the screening is between 1 and 2. So dozens of electrons in such atom, are felt by 1s electron as just a ~2 elementary charges.
And 1s electron is ~10^-10m distance - getting to femtometer distance, this screening goes to practically 0.
This vanishing of screening is a consequence of the shell theorem: https://en.wikipedia.org/wiki/Shell_theorem

So screening of shell electrons is practically negligible during the most crucial part of fusion process (pico->femtomemter, Coulomb potential says that you need 1000x more energy to get to 1fm than to 1pm).
The only hope for fusion in 1000K is that a single electron stays between these two collapsing nuclei.