First of all, quantum mechanics was motivated by the thought of semiconductors. One of the primary use cases of it was explaining the photoelectric effect [1]. Secondly, other primary motivations for QM were explaining and predicting chemical reactions, radiation sources, and nuclear energy.
Secondly, probability and statistics - as you note - were invented to understand/solve gambling problems. Virtually every early advance was then made by people attempting to use it. These include Gauss predicting the orbit of Ceres, Graunt and Halley (yes, he also spotted Halley's comet) doing insurance, Galton and Pearson studying evolution and developing eugenics, and Gosset using statistics to brew better beer.
Probability and statistics are perhaps the worst possible example of pure research that - purely by chance - happens to be useful later.
[1] Interestingly, the classical belief that the photoelectric effect proves the quantization of light is wrong. The Schrodinger equation + continuous electromagnetic fields actually exhibit the photoelectric effect.
> First of all, quantum mechanics was motivated by the thought of semiconductors.
Excuse me? Quantum mechanics was developed in the 1920s, long before any thought of applying it to any practical problems. Semiconductor research came much later, and that was also largely pure research into material properties carried out at Bell Labs, a facility noted for its isolation from any commercial application of its work.
So, entirely false.
> One of the primary use cases of it was explaining the photoelectric effect [1].
You're confused. Einstein explained the photoelectric effect in 1905, then spent the remainder of his career objecting to the quantum theories that developed from this starting point, all without any practical applications in mind by any of the participants.
> Interestingly, the classical belief that the photoelectric effect proves the quantization of light is wrong.
There is no such belief, so discussing it is pointless.
> Probability and statistics are perhaps the worst possible example of pure research that - purely by chance - happens to be useful later.
They're examples of pure research into mathematical ideas that --purely by chance -- happen to have practical applications. How is that a bad example of the point that pure research is the source of most insights into nature?
Claiming that quantum mechanics (QM) was motivated by semiconductors is bordering on discussing in bad faith.
A glance at [1] will show that people were thinking about issues leading up to QM for several decades. Planck's equation relating energy to frequency of light (in several ways the first "quantum" idea that conceived what we today call Planck's constant) was motivated by understanding the "ultraviolet catastrophe" [2] (which was a purely "theoretical" endeavour as some would call it today). Planck's work preceeded Einstein's explanation of the photoelectric effect by several years. Even when the photoelectric effect was observed, it was first noticed in zinc (IIRC); it was only in the 1930s that QM was applied to understand the functioning of semiconductors.
You are confusing all the things we use QM for today with all the reasons for which it was first conceived. Moany of those reasons of course spurred development in QM after it was conceived -- but none of those motivations would have conceived QM.
With regards to your comment on the development of probability:
There was always a reason/purpose something was conceived. So claiming that it was "motivated by applications" is tautological. The relevant question to ask is whether the applications today are different from the original motivations. If they are, then frankly, it doesn't matter what the original motivations were... the idea would have been difficult to conceive starting with the eventual application in mind. Eg: Without an understanding of probability, linear algebra and differential equations, there would have been no quantum mechanics. Somebody observing the photoelectric effect could not have developed those tools for their "application".
I notice your other comment on the thread (OP) talks in analogy with physical training. IMHO, such an analogy is misguided for endeavours which cannot be reasonably well specified so as to be manageable (in that it can be managed, with the goal in mind). Basic research is often not amenable to that because it has tons of unknown unknowns [3].
The photoelectric effect was first discovered in silver chloride solution. I don't know that much about the energy bands of silver chloride, so I won't comment about whether that was a semiconductor. (I also know very little about liquids, basically all the physics I did happened in semiconductors.)
The first solid state demonstration was in selenium, which is a semiconductor. This is what I was thinking of when I said that the photoelectric effect was semiconductor physics.
The relevant question to ask is whether the applications today are different from the original motivations. If they are, then frankly, it doesn't matter what the original motivations were... the idea would have been difficult to conceive starting with the eventual application in mind.
You are defining "pure" in a far more expansive way than the article does. Your definition is actually so broad that it doesn't contradict the article at all.
The article claims that science, with the goal of building cool military applications (or presumably life tables or brewing beer) will work better than curiosity driven applications. Then it claims the fruits of those labors will be useful elsewhere. Now you seem to be agreeing with this, or at least not disagreeing.
Note that the article isn't saying "don't figure out fundamental physics". It's saying "go build a giant wall of ice to keep the mexicans out and a better understanding of pure thermodynamics will be one output of that project."
Also note that I'm not arguing for the premise of the article, necessarily. I'm simply arguing that it can't be casually dismissed without even an argument. My analogy is meant to be suggestive, not to prove the point.
> The photoelectric effect was first discovered in silver chloride solution. I don't know that much about the energy bands of silver chloride, so I won't comment about whether that was a semiconductor.
Had the first example of the photoelectric effect originated in a semiconductor, that cannot be used to argue that the research was motivated by the goal of practical application. By that reasoning, the fact that particle physics is about atoms, and that atoms can be used to make weapons, could be used to construct an absurd argument that all research that involves atoms has the ultimate goal of designing weapons.
> The article claims that science, with the goal of building cool military applications (or presumably life tables or brewing beer) will work better than curiosity driven applications.
The phrase "curiosity driven applications" assumes what it should be proving. Not all curiosity into nature has application in mind, indeed that's not now pure research is defined.
> You are defining "pure" in a far more expansive way than the article does.
Pure research is research meant to discover properties of nature, without any concern for practical application. That's hardly worth discussing as though there's any controversy about the definition.
> Without an understanding of probability, linear algebra and differential equations, there would have been no quantum mechanics. Somebody observing the photoelectric effect could not have developed those tools for their "application".
I disagree strongly, and history might too. For example, Heisenberg invented matrix multiplication for quantum mechanics. In general, physicists have been very happy to invent entire fields of mathematics (eg, calculus!) for their direct application. At the very least, I think you're overselling your point.
Taking nothing away from Heisenberg, he reformulated a particular quantum system in the new language. But in order to be able to apply QM to all kinds of systems, one needs to also reformulate it in a universal language. At that point, Max Born interpreted Heisenberg's example using his knowledge of math -- Here's the story I found: https://en.wikipedia.org/wiki/Heisenberg%27s_entryway_to_mat...
----
Max Born had two seminal contributions:
1. Interpreting the noncommutative structure in Heisenberg's observation as linear operators
2. The "Born rule" that relates amplitudes involving the wavefunction (quantum state) to probabilities.
For both of those, he used existing math knowledge. He did not re-invent linear algebra or probability theory. And differential equations were part of the standard toolkit of physicists by then (given successes of the theory of heat and the wave theory of light)
Secondly, probability and statistics - as you note - were invented to understand/solve gambling problems. Virtually every early advance was then made by people attempting to use it. These include Gauss predicting the orbit of Ceres, Graunt and Halley (yes, he also spotted Halley's comet) doing insurance, Galton and Pearson studying evolution and developing eugenics, and Gosset using statistics to brew better beer.
Probability and statistics are perhaps the worst possible example of pure research that - purely by chance - happens to be useful later.
[1] Interestingly, the classical belief that the photoelectric effect proves the quantization of light is wrong. The Schrodinger equation + continuous electromagnetic fields actually exhibit the photoelectric effect.