Celebrating the Birth Centenary of Quantum Mechanics: A Historical Perspective

[NNadir]

The paper I'll discuss in this post is a nice retrospective published in the following paper: Celebrating the Birth Centenary of Quantum Mechanics: A Historical Perspective Venkat Venkatasubramanian Industrial & Engineering Chemistry Research 2025 64 (19), 9443-9456

The paper is open for reading to the general public, anyone can read it.

It's been many years since I last took a formal course in quantum chemistry, decades, the last concerning conservation of orbital symmetry in organic reactions, and so the joy of the subject has slipped away. When I was a kid I used to pull out old texts and work problems; I'm years away, decades away, from that now.

What I recall was learning that Planck's insight actually came from understanding that the "ultraviolet catastrophe" expressed by the Rayleigh-Jeans Law came from treating the derivation not by integration (by the treatment of as a limit) but by the expediency of treating it as a summation, sort of the reverse of what one learns in an introductory calculus course. As I understood it - and I could be wrong - Planck regarded it initially as a kind of mathematical trick - that fit the physical world, although well less than a decade later, in explaining the photoelectric effect, Einstein showed it to be more than that, followed by Bohr's "planetary hydrogen atom" (which proved to be somewhat naive, but was astounding in explaining the spectra of hydrogen atoms.

The joy of this particular account in this paper includes, from my perspective, an account from Planck, in his scientific autobiography, his ruminations on the 2nd law of thermodynamics, which remained obscure in the late 19th century at the time he introduced the concept (then purely mathematical) of "quanta." (The Second Law of Thermodynamics, which remains unaffected in its reality by wishful thinking, is still obscure in popular circles, which is why we hear so much bullshit to this day about batteries, and worse, hydrogen: Schemes to store energy are schemes to waste energy.)

An excerpt from the text, although the full article is free to read:

Let us hear about the first step from Planck himself from his scientific autobiography: (17)

“In fact, my previous studies of the Second Law of Thermodynamics came to stand me in good stead now, for at the very outset I hit upon the idea of correlating not the temperature but the entropy of the oscillator with its energy. It was an odd jest of fate that a circumstance which on former occasions I had found unpleasant, namely, the lack of interest of my colleagues in the direction taken by my investigations, now turned out to be an outright boon. While a host of outstanding physicists worked on the problem of spectral energy distribution, from both the experimental and theoretical aspects, every one of them directed his efforts solely toward exhibiting the dependence of the intensity of radiation on the temperature.

On the other hand, I suspected that the fundamental connection lies in the dependence of entropy upon energy. As the significance of the concept of entropy had not yet come to be fully appreciated, nobody paid any attention to the method adopted by me, and I could work out my calculations completely at my leisure, with absolute thoroughness, without fear of interference or competition ... In this way, a new radiation formula was obtained, and I submitted it for examination to the Berlin Physical Society, at the meeting on October 19, 1900.”

Although Rudolf Clausius introduced the concept of entropy in 1864, it remained undervalued by the scientific community, surprisingly, for nearly three decades. This highlights the significant amount of time required for revolutionary concepts to gain widespread acceptance. Reflecting on this, Planck later remarked rather sardonically: (17)

“A new scientific truth does not triumph by convincing its opponents and making them see the light, but rather because its opponents eventually die out, and a new generation grows up that is familiar with it.”

That last comment is, more than a century later, a rather hopeful comment.

Regrettably, Planck's papers were destroyed in an allied bombing of Germany in World War II. He managed to outlive Hitler, who decimated German science just as the orange slime mold in the US White House is decimating American sciences today.

Have a nice weekend.

[erronis]

1. I know there have been studies of when great discoveries are made based on the age of the person.

Somewhat tangential to Planck's comment

“A new scientific truth does not triumph by convincing its opponents and making them see the light, but rather because its opponents eventually die out, and a new generation grows up that is familiar with it.”

I wonder if anyone has researched and published any studies that show when some of these great minds actually change their viewpoints based on new evidence. And how old they were, how entrenched into the "common wisdom" or ideology.

It has to be hard at the anticipated end-of-life to admit that one might be wrong.

[NNadir]

2. The work that defines my current field was done by old men.

John Fenn, the discoverer of electrospray ionization (ESI), the key element in modern mass spectrometry, did his Nobel Prize winning work in his 60's, at the end of his career. He was semi-retired, a forced retirement. His work was based on the understanding of the "Taylor Cone" a paper published by Geoffrey Taylor when he was 78 in 1964.

Fenn's work on ESI took place after he had reached mandatory retirement ,(70) age at Yale. (He and Yale spent years suing each other over the rights to the ESI patent. Fenn lost the lawsuit.)

He was 85 when he was awarded the prize.

I think the myth that people can only produce great science when they are young, is that when young people do great science that rises to prominence, they can be distracted by their fame and find it hard to continue their work. Richard Feynman complained about being awarded the Nobel Prize without his consent, because it distracted him.

Obscurity can be a good thing for doing good work. Experience, and failure, are also benefits that can lead to good work.