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comment by am_Unition
am_Unition  ·  3068 days ago  ·  link  ·    ·  parent  ·  post: Einstein’s Lost Hypothesis.

The shitty thing about quantum mechanics is that you need a knowledge of vector calculus, linear algebra, differential equations, and many other uncommon mathematical concepts to understand it. Then, when you can do the mathematics, and you're actually making (correct) predictions about quantum mechanical systems, just about everyone's natural reaction is to step back and say "what the fuck is going on here?". That's the best way I can describe it, because the way things work is not reducible to English. So of course I'll make an attempt!

When the wavefunctions (akin to probability distributions - the likelihood of finding something somewhere) of particles overlap (when they are physically near each other, for instance), changes to one can affect the other. In that case, you can treat the two (or many, many, more) as a system, and the mathematics change such that strange characteristics emerge due to behavior of the collective system. One familiar result is the physics of electrical conductors and insulators. In conductors, the Fermi Level permits free movement of electrons between atoms at room temperature.

As for this possibility of transmutation? It's fair to be skeptical that any phenomenon is happening at all, with limited reproducibility, and I'm only a little less wary of this article than the new "EM microwave resonant cavity propulsion" stuff; they both seem to violate what we believe to be universal laws (conservation of energy and momentum, respectively). But since behavior at the quantum scale is so weird, people are hesitant to say that we understand exactly how or why this method of transmutation would be impossible. Personally, I'd throw more money at this than the EM-drives, but truthfully, I don't expect either to pan out. Still got my fingers crossed for both though.

And that's all I can really say about it, not much more than the article, sorry. Man, I just left my "cobbler's job", too.

Edit: So I brought this up with one of my more "nuclear-inclined" classmates for discussion. Here's the conclusion we (mostly he) came to:

The proton's rest mass is 938.2 MeV, and the electron only clocks in at 511 keV. The neutron's rest mass is 939.5 MeV; that's a +1300 keV difference compared to the proton. So for an electron + a proton, you still lack 789 keV in energy to make the neutron. That's why the article mentions requiring an electron acceleration potential of something on the order of 1 MeV to bridge the gap. This formulation is oversimplified, but the general idea is more clear than in the article (I hope).

BUT, we now know that nucleons aren't just elementary particles (like the electron and other leptons), but that there are partons comprising them. These partons (quarks and gluons) are a system of particles (like we talked about earlier) which can behave in ways we may not yet fully understand, especially when interacting with a collective group of electrons. We ended up agreeing that it was possible for an electron to interact with a parton in a way that somehow bridged this energy gap, similar to the idea of quantum tunneling. But how this process would yield a large enough amount of neutrons to transmutate enough atoms for it to be significant isn't clear.

So then we talked about applications to energy consumption. That debate is ongoing, and I'll update this thread later. Still seems to me that for this to be a worthwhile pursuit, it would violate energy conservation, and my friend doesn't disagree.





ButterflyEffect  ·  3066 days ago  ·  link  ·  

The good news is that I have exposure to vector calculus, some linear algebra, and diff-eq (my personal favorite when it comes to math if only for it's applications in control functions). So then do the mathematics change from handling everything on an individual level (electrons in an orbital?) to treating it as a bulk?

Dammit, stuff like this makes me appreciate physics so much and wish I had a grad level understanding of it.

am_Unition  ·  3063 days ago  ·  link  ·  

Just saw your reply, sorry. I've had a realization of how I need to better manage my notifications, now I understand why I've lost some responses.

    So then do the mathematics change from handling everything on an individual level (electrons in an orbital?) to treating it as a bulk?

Yep.

A standard level graduate school education usually leaves the student with a firm understanding of only one electron in a Hydrogen atom, where there is similarly only one proton in the nucleus to pull on it (the Coulomb force dominates over gravity at this scale). The resulting solutions to the Schrödinger equation form a set of orthonormal/orthogonal spherical harmonics, describing the electron's spatial wave function (the probability distribution I mentioned earlier) that depend solely on the electron's energy level. As soon as you add more particles (protons or electrons) to the system, things get complicated fast. In my curriculum, I have also analyzed a system of two electrons, with no proton. That's also a rather unintuitive system due to a quantum mechanical parameter called "spin" that has no classical analog, i.e. there's no familiar way to think of it. You've just got to accept its existence and move on with your life (THIS IS DIFFICULT).

But we came up with clever ways of treating systems of particles, and as you've guessed, the mathematics do indeed change. Handling systems of atoms and molecules is often best left to chemistry, which can be thought of as a result of quantum mechanics for large systems of particles. I brought up solid-state physics previously, which is also the application of quantum mechanical theory to a particularly interesting landscape; atoms connected in varying geometric lattice configurations via sharing of electrons. In undergrad, I took a solid-state physics course cross-listed as grad-level, but I'd have to take it about three more times to feel comfortable with all of the content.

Do you have any links on control functions? :)

    Dammit, stuff like this makes me appreciate physics so much and wish I had a grad level understanding of it.

I love me some physics, but maybe it's too much when you're spending 1/3 of your semester learning the culmination of several people's lifework. And that's why when I look at my homework from last month, I don't even remember doing it (or most importantly, how to do it).