FAQ - How fusion occurs

If you wonder how/why fusion works, or how/why the Fusor works, look here first.
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Richard Hull
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FAQ - How fusion occurs

Post by Richard Hull » Mon Jul 20, 2020 5:24 pm

Before we think fusion is a straight forward process. We need to focus on how fusion is done at the particulate level. There are three things that make fusion possible for energetic output. (That is right! Not all fusions are exoergic!)

1. probability - luck of the draw - quantifiable statistics
2. spooky probability - unnatural action with no classical explanation
3. quantum uncertainty - very well defined mathematical probability within quantum mechanics (fusion cross sections for specific reactions)

There you have it. Within all the probabilities above are found the only genuine methodologies of actually doing fusion. Exoergic fusion is not a sure thing at the particulate level, regardless of the energy of any particle attempting it! This means that for 10 keV particles, 50 keV particles, 100 keV particles and 1 meV particles, fusion is and always will be a crap shoot! Remember this fact!

In all probabilistic endeavors, the probabilities of a specific outcome always go up by using billions of dice throws, or by "loading" the dice, or by using dice with two faces that are the same.

In nuclear fusion we can do all of these, but within narrow limits. To get net energy out we must supply a good bit of "seed energy" into throwing billions of dice (particles). The net energy out depends on how we load the dice or double side them. Remember, even with this loading and cheating, we are still governed by the three rules of fusion stated above.

In most all cases when attempting fusion, we work with ions in collision in an attempt to make them fuse. These are all positive nuclei. They do not want to fuse due to the powerful force of coulombic repulsion. This repulsion represents a potential hill or coulombic barrier that must be defeated before the strong, very short range nuclear force can act to fuse the nuclei and release fusion energy.

Hill? Barrier? Uncertainty? - phooey I can do fusion real easy. Watch me!

1. To do fusion, we typically design a mechanical system whereby we have free particles in abundance at ideal conditions of uniform relative energy levels that are ideal from the standpoint of well understood physics. (This is loading the dice) and knock out number 1 of the above criteria. Here, we seem to be ahead of the game.

2. The classical probabilities in number 2 above are fouled by something beyond luck of the draw even with loaded dice.

3. Here is the real fly in any fusion ointment. There is a coulombic barrier, a potential hill that must be defeated, here, our loaded dice are still of great value for they are arriving at a good place on the energy delivery region such that they may Quantum tunnel at a good bit lower energy that it takes to go over the hill. Instead, they burrow through it in a spooky fashion with a special form of probability found only in the quantum world.

Let us stop here. you may ask, "Hey! Why don't we blast the hill with a beam of particles well above the hill's value?" Sorry.... If we do that, we still may not fuse, but disrupt the nuclei we want to fuse with. Even if we fuse, the extra energy we needed to "beat the barrier or hill" will usually exceed that of the fusion energy gained as we have blasted billions of these above "Barrier" particles using a lot of input energy!

Back to the quantum probability issue. How does this work? It turns out that our particles at fusion energy that are at optimum probability are about 4.5 Fermi size. When they slam into the hill or even get close to it, they may not be a particle at all!!... Spooky? You got it, pal.... But, wait, this can be a good thing!! What??!! Yes! While not in a quantized state of physical existence, our bombarding particle can re-materialize on the other side of the barrier where the nuclear force is strong and fusion can and will occur with net fusion energy output far beyond the energy of our successful tunneled particle.

In the end, for all our dice loading, we are hard against yet another spooky probability associated with the small world of quantum physics. Quantum tunneling is the only way to fuse with less energy in than we get out via fusion. Quantum tunneling is the desiderata here! It is the only way net energy fusion is done.

Let's recap what we do here to do fusion

We load the dice by spending a lot of energy to ace out standard, well understood statistics, via well organized particle physics. We attempt to make a pure beam or stream of accelerated, bombarding particles or particles bumping into each other at thermal energies at this dice loaded level to assist in the quantum tunneling process. It is difficult and near impossible to warrant every particle will be at the same energy. (maxwellian distribution).... So, some particles of less than ideal energy are more or less wasted energy, up front! Unfortunately, not all the ideally energetic particles will pop out of existence at the ideal moment at or near the barrier and will, themselves, be energy lost in the process of doing fusion. The natural thing is to assure that there are so many particles arriving at fusion energy per unit time that we "beat" the quantum tunneling probability working against fusion!!! It is called "ignition".... Ignition is related to something called the Lawson criterion which defines the methodology for destroying all the probabilistic negativity working against net, power producing fusion into a continuous certainty as long as all the criteria are met.

Yes, fusion is very easy to do by spending a lot of energy to get virtually nothing in energetic return for all the fusion done versus the energy poured in to actually do fusion. This is our fusor, the tokamak, the stellarator, and all the other working fusion machines ever assembled. Our fusors are the only one capable of doing fusion on a continuous basis! None make net continuous fusion energy above the input energies needed to operate them....

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
Retired now...Doing only what I want and not what I should...every day is a saturday.

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