Understanding lasers, semiconductors and other technical stuff

I wrote a lot of papers but most of them – if not all – deal with very basic stuff: the meaning of uncertainty (just statistical indeterminacy because we have no information on the initial condition of the system), the Planck-Einstein relation (how Planck’s quantum of action models an elementary cycle or an oscillation), and Schrödinger’s wavefunctions (the solutions to his equation) as the equations of motion for a pointlike charge. If anything, I hope I managed to restore a feeling that quantum electrodynamics is not essentially different from classical physics: it just adds the element of a quantization – of energy, momentum, magnetic flux, etcetera.

Importantly, we also talked about what photons and electrons actually are, and that electrons are pointlike but not dimensionless: their magnetic moment results from an internal current and, hence, spin is something real – something we can explain in terms of a two-dimensional perpetual current. In the process, we also explained why electrons take up some space: they have a radius (the Compton radius). So that explains the quantization of space, if you want.

We also talked fields and told you – because matter-particles do have a structure – we should have a dynamic view of the fields surrounding those. Potential barriers – or their corollary: potential wells – should, therefore, not be thought of as static fields. They result from one or more charges moving around and these fields, therefore, vary in time. Hence, a particle breaking through a ‘potential wall’ or coming out of a potential ‘well’ is just using an opening, so to speak, which corresponds to a classical trajectory.

We, therefore, have the guts to say that some of what you will read in a standard textbook is plain nonsense. Richard Feynman, for example, starts his lecture on a current in a crystal lattice by writing this: “You would think that a low-energy electron would have great difficulty passing through a solid crystal. The atoms are packed together with their centers only a few angstroms apart, and the effective diameter of the atom for electron scattering is roughly an angstrom or so. That is, the atoms are large, relative to their spacing, so that you would expect the mean free path between collisions to be of the order of a few angstroms—which is practically nothing. You would expect the electron to bump into one atom or another almost immediately. Nevertheless, it is a ubiquitous phenomenon of nature that if the lattice is perfect, the electrons are able to travel through the crystal smoothly and easily—almost as if they were in a vacuum. This strange fact is what lets metals conduct electricity so easily; it has also permitted the development of many practical devices. It is, for instance, what makes it possible for a transistor to imitate the radio tube. In a radio tube electrons move freely through a vacuum, while in the transistor they move freely through a crystal lattice.” [The italics are mine.]

It is nonsense because it is not the electron that is traveling smoothly, easily or freely: it is the electrical signal, and – no ! – that is not to be equated with the quantum-mechanical amplitude. The quantum-mechanical amplitude is just a mathematical concept: it does not travel through the lattice in any physical sense ! In fact, it does not even travel through the lattice in a logical sense: the quantum-mechanical amplitudes are to be associated with the atoms in the crystal lattice, and describe their state – i.e. whether or not they have an extra electron or (if we are analyzing electron holes in the lattice) if they are lacking one. So the drift velocity of the electron is actually very low, and the way the signal moves through the lattice is just like in the game of musical chairs – but with the chairs on a line: all players agree to kindly move to the next chair for the new arrival so the last person on the last chair can leave the game to get a beer. So here it is the same: one extra electron causes all other electrons to move. [For more detail, we refer to our paper on matter-waves, amplitudes and signals.]

But so, yes, we have not said much about semiconductors, lasers and other technical stuff. Why not? Not because it should be difficult: we already cracked the more difficult stuff (think of an explanation of the anomalous magnetic moment, the Lamb shift, or one-photon Mach-Zehnder interference here). No. We are just lacking time ! It is, effectively, going to be an awful lot of work to rewrite those basic lectures on semiconductors – or on lasers or other technical matters which attract students in physics – so as to show why and how the mechanics of these things actually work: not approximately, but how exactly – and, more importantly, why and how these phenomena can be explained in terms of something real: actual electrons moving through the lattice at lower or higher drift speeds within a conduction band (and then what that conduction band actually is).

The same goes for lasers: we talk about induced emission and all that, but we need to explain what that might actually represent – while avoiding the usual mumbo-jumbo about bosonic behavior and other useless generalizations of properties of actually matter- and light-particles that can be reasonably explained in terms of the structure of these particles – instead of invoking quantum-mechanical theorems or other dogmatic or canonical a priori assumptions.

So, yes, it is going to be hard work – and I am not quite sure if I have sufficient time or energy for it. I will try, and so I will probably be offline for quite some time while doing that. Be sure to have fun in the meanwhile ! 🙂

Post scriptum: Perhaps I should also focus on converting some of my papers into journal articles, but then I don’t feel like it’s worth going through all of the trouble that takes. Academic publishing is a weird thing. Either the editorial line of the journal is very strong, in which case they do not want to publish non-mainstream theory, and also insist on introductions and other credentials, or, else, it is very weak or even absent – and then it is nothing more than vanity or ego, right? So I think I am just fine with the viXra collection and the ‘preprint’ papers on ResearchGate now. I’ve been thinking it allows me to write what I want and – equally important – how I want to write it. In any case, I am writing for people like you and me. Not so much for dogmatic academics or philosophers. The poor experience with reviewers of my manuscript has taught me well, I guess. I should probably wait to get an invitation to publish now.

Quantum Physics: A Survivor’s Guide

A few days ago, I mentioned I felt like writing a new book: a sort of guidebook for amateur physicists like me. I realized that is actually fairly easy to do. I have three very basic papers – one on particles (both light and matter), one on fields, and one on the quantum-mechanical toolbox (amplitude math and all of that). But then there is a lot of nitty-gritty to be written about the technical stuff, of course: self-interference, superconductors, the behavior of semiconductors (as used in transistors), lasers, and so many other things – and all of the math that comes with it. However, for that, I can refer you to Feynman’s three volumes of lectures, of course. In fact, I should: it’s all there. So… Well… That’s it, then. I am done with the QED sector. Here is my summary of it all (links to the papers on Phil Gibbs’ site):

Paper I: Quantum behavior (the abstract should enrage the dark forces)

Paper II: Probability amplitudes (quantum math)

Paper III: The concept of a field (why you should not bother about QFT)

Paper IV: Survivor’s guide to all of the rest (keep smiling)

Paper V: Uncertainty and the geometry of the wavefunction (the final!)

The last paper is interesting because it shows statistical indeterminism is the only real indeterminism. We can, therefore, use Bell’s Theorem to prove our theory is complete: there is no need for hidden variables, so why should we bother about trying to prove or disprove they can or cannot exist?

Jean Louis Van Belle, 21 October 2020

Note: As for the QCD sector, that is a mess. We might have to wait another hundred years or so to see the smoke clear up there. Or, who knows, perhaps some visiting alien(s) will come and give us a decent alternative for the quark hypothesis and quantum field theories. One of my friends thinks so. Perhaps I should trust him more. 🙂

As for Phil Gibbs, I should really thank him for being one of the smartest people on Earth – and for his site, of course. Brilliant forum. Does what Feynman wanted everyone to do: look at the facts, and think for yourself. 🙂

Feynman’s religion

Perhaps I should have titled this post differently: the physicist’s worldview. We may, effectively, assume that Richard Feynman’s Lectures on Physics represent mainstream sentiment, and he does get into philosophy—less or more liberally depending on the topic. Hence, yes, Feynman’s worldview is pretty much that of most physicists, I would think. So what is it? One of his more succinct statements is this:

“Often, people in some unjustified fear of physics say you cannot write an equation for life. Well, perhaps we can. As a matter of fact, we very possibly already have an equation to a sufficient approximation when we write the equation of quantum mechanics.” (Feynman’s Lectures, p. II-41-11)

He then jots down that equation that Schrödinger has on his grave (shown below). It is a differential equation: it relates the wavefunction (ψ) to its time derivative through the Hamiltonian coefficients that describe how physical states change with time (Hij), the imaginary unit (i) and Planck’s quantum of action (ħ).

hl_alpb_3453_ptplr

Feynman, and all modern academic physicists in his wake, claim this equation cannot be understood. I don’t agree: the explanation is not easy, and requires quite some prerequisites, but it is not anymore difficult than, say, trying to understand Maxwell’s equations, or the Planck-Einstein relation (E = ħ·ω = h·f).

In fact, a good understanding of both allows you to not only understand Schrödinger’s equation but all of quantum physics. The basics are this: the presence of the imaginary unit tells us the wavefunction is cyclical, and that it is an oscillation in two dimensions. The presence of Planck’s quantum of action in this equation tells us that such oscillation comes in units of ħ. Schrödinger’s wave equation as a whole is, therefore, nothing but a succinct representation of the energy conservation principle. Hence, we can understand it.

At the same time, we cannot, of course. We can only grasp it to some extent. Indeed, Feynman concludes his philosophical remarks as follows:

“The next great era of awakening of human intellect may well produce a method of understanding the qualitative content of equations. Today we cannot. Today we cannot see that the water flow equations contain such things as the barber pole structure of turbulence that one sees between rotating cylinders. We cannot see whether Schrödinger’s equation contains frogs, musical composers, or morality—or whether it does not. We cannot say whether something beyond it like God is needed, or not. And so we can all hold strong opinions either way.” (Feynman’s Lectures, p. II-41-12)

I think that puts the matter to rest—for the time being, at least. 🙂

Planck’s quantum of action

I find it most amazing that – with few physical laws and geometry formulas – we are able to understand reality.

These laws – Maxwell’s equations, Einstein’s mass-energy equivalence relation, and the Planck-Einstein relation – are not easy. The geometry formulas – Euler’s formula, basically – are not easy either. But once you get them, all falls into place—like Enlightenment (or kensho, satorinirvana, etc. if you’d happen to like Buddhist philosophy). 🙂

All has a resonant frequency: photons, electrons, protons, neutrons, atoms, molecules, complex systems—all that is stable. Unstable particles and systems do not obey the Planck-Einstein relation: ω = E/ħ. They die out: they are short-lived transients or even shorter-lived resonances. We should not refer to them as particles or particle-systems, and we need non-equilibrium math to analyze them.

It is all most beautiful. I will, therefore, not say anything more about it here. I’ve written about the nitty-gritty elsewhere.