Albert Einstein faced extremely complex calculations to solve great riddles of the universe.
And, at the same time, it withstood the ferocious onslaught of Nazi scientists who —moved by envy, by the anxiety of feeling backward in the face of new theories and inspired by racist ideas— tried to stop the intellectual revolution generated by one of the most brilliant physicists of all the time.
And they weren’t just any enemies.
For years, two Nobel laureates in physics, Philipp Lenard and Johannes Stark, led a campaign of discredit against Einstein, based on a science influenced by Nazi ideology.
Their strategy was to impose a supposed “Aryan physics”, as opposed to what they considered a physics hijacked by an also supposed “Jewish spirit”.
Lenard and Stark refused to acknowledge the two most audacious theories of the time, both driven by Jews: Einstein’s relativity and Niels Bohr’s quantum mechanics.
Such was the anger of Lenard and Stark that historians claim their efforts were comparable to wanting to become the “Führer of physics.”
How did Lenard and Stark’s hatred of Einstein arise, how did their campaign of persecution go, and how far did they go in their effort to impose “Aryan physics”?
an uncomfortable genius
Einstein, of Jewish origin and increasingly recognized worldwide, was very uncomfortable for the Nazis.
Furthermore, his success aroused jealousy in Lenard—also a brilliant physicist, but without many of the attributes that made Einstein special.
Lenard received the Nobel Prize in Physics in 1905 for his study of cathode rays.
However, he had “limited intellectual depth and was emotionally and imaginatively stunted,” as scientific writer and former Nature editor Philip Ball described in his book Serving the Reich: The Struggle for the Soul of Physics under Hitler (“Serving the Reich: The Struggle for the Soul of Physics Under Hitler”, in free translation).
Lenard was a largely experimental scientist and, according to Ball, his mathematical skills weren’t enough for him to understand bold ideas like relativity.
His inability to understand relativity led him to disqualify it as a theory. The fact that he was supported by the international academic community made him think it was a conspiracy.
Lenard clung to the idea that what we now know as spacetime was the so-called ether—and he called relativity a “Jewish fraud.”
Stark’s case was similar.
In 1919, he had received the Nobel Prize in Physics for discovering that an electric field causes changes in the spectrum of light, a phenomenon known today as the Stark Effect.
Stark was also an experimentalist who was overwhelmed by the mathematical complexity that physics was taking on.
And like Lenard, he was also an extremist nationalist whose ideas were radicalized after World War I.
His nationalism was such that he clashed with Nazi officials because, from his point of view, they were not “Nazi enough”.
Lenard and Stark joined the Nazis since before the party took power.
Lenard had been critical of relativity since 1910, but it wasn’t until 1920 that he began to add racist elements to his attacks, according to Ball.
His speech was based on the fact that while Aryans clung to data and experimental work, Jews were engrossed in abstract speculation.
“Lenard’s argument was that any human endeavor, including science, was defined by race,” Alex Wellerstein, a science historian specializing in the history of eugenics, told BBC News Mundo (BBC’s Spanish service).
“Lenard argued that different races had different physics.”
Since relativity and quantum mechanics include factors such as uncertainty and relativism, Lenard saw in these theories a threat to a well-organized society and a path to chaos.
In contrast, “Aryan physics,” which included experiments that were on the rise in 19th-century Germany, emphasized tangible truths, in science that was applied to real problems and a strictly experimental approach to reality.
Lenard and Stark’s arguments generally lacked “substantial criticism” of Einstein’s ideas, explains Wellerstein. From a scientific point of view, they were weak.
The most generous one could say about the anti-Einstein arguments, says Wellerstein, is that at that time many aspects of their theories had not been completed, which opened the door for characters like Lenard or Stark to offer alternative explanations while ignoring the robust aspects. of Einstein’s ideas.
In 1931, hundreds of philosophers and scientists participated in a publication against Einstein’s ideas.
Wellerstein, however, points out that “Aryan physics” didn’t really enjoy much popularity.
“I don’t know an exact number (of followers), but the reports I’ve read make it seem like it was relatively small,” says the expert.
“You have to keep in mind that the ideas Lenard and Stark were promoting weren’t very interesting from a functional physics point of view. It was the physics of the past, not the future.”
What did Hitler think of all this?
The top Nazi leader was obviously aware of Einstein, world famous for his 1921 Nobel and for being a dissident who refused to return to Germany after the rise of the Nazis.
Wellerstein, however, says he didn’t see much evidence that Hitler considered Lenard and Stark’s campaign worthy of his personal attention.
“Hitler didn’t need sophisticated reasons to hate Jews and their creations,” says the historian.
How did Einstein react?
In general, Einstein was not very involved in the attacks of his detractors.
In 1920, however, he published a letter in response to one of Lenard’s orchestrated attacks on relativity.
“I admire Lenard as a professor of experimental physics,” Einstein wrote. “However, he has yet to achieve something in theoretical physics, and his objections to the theory of general relativity are so superficial that I have not considered it necessary, until now, to answer them in detail.”
According to Wellerstein, Einstein walked away from public debates about his theories and let other physicists discuss them.
“As far as I know, he didn’t try to influence debates inside Nazi Germany, perhaps knowing that the only thing he would do is stir them up,” Wellerstein said.
The failure of “Aryan physics”
Over time, the ideas of Lenard and Stark were weakened by the pragmatism of Nazi officials.
In the middle of the war, these leaders were more interested in getting results, developing weapons and technology, than in discussing interpretation of physics.
“The Nazis never adopted ‘Aryan physics’ as part of their official ideology,” says Wellerstein.
“‘Aryan physics’ failed spectacularly, because even the Nazis had a hard time taking it seriously, especially during the war.”
Ball, for his part, explains that it was clear to the Nazis that the Jews who proposed quantum theory and relativity were the ones who really knew the secrets of atoms, and that only they were able to turn their findings into practical applications.
After the end of the war came the Nuremberg trials in 1945.
At the time, Lenard was 82 years old, and although he was briefly imprisoned and stripped of his title of professor emeritus at the University of Heidelberg, he was never convicted and died in 1947, as Ball explains in his book.
Stark was also spared a severe sentence.
In 1947 he was sentenced to four years of field work, but the sentence was suspended twice and he died without serving the sentence in 1957, aged 83.
In 2020, the International Astronomical Union decided that two craters on the Moon that had been named Lenard and Stark in honor of these scientists should no longer be named that way.
There are voices that go further and ask for their respective Nobel Prizes to be withdrawn.
Meanwhile, Einstein’s General Relativity stands out as one of the most important theories in modern physics, hoping someone will beat it with really solid arguments.