## Is Relativity The Case?

Of course, just being a novel idea is not sufficient for the acceptance of a theory. It has to pass experimental tests and here too, nothing was simple for Einstein.

Remember that Lorentz's theory of the ether was in many ways predictably identical to Relativity. That included a Lorentzian view of mass which also would predictably increase with speed (relative to the ether). In 1901 there were competing theories based on ideas of electromagnetism that differed from Maxwell's and Lorentz'. Walter Kaufmann, whom we'll learn more of later, took on the challenge to measure whether the mass of an electron varied with velocity. More particularly, he measured the so-called "charge to mass" ratio, which can be determined by accelerating a charged particle through an appropriately designed sequence of electric and magnetic fields. (We'll learn about this when we discuss the discovery of the electron by the Englishman, J.J. Thomson.)

Kaufmann was a very patient and skilled experimenter, but he got it wrong. His measurements were analyzed by him to disfavor the Lorentz prediction (and of course consequently, the 1905 Einstein prediction). Kaufmann did experiments in 1901, 1902, 1903, and 1905 and concluded:

> "*The prevalent results decidedly speak against the correctness of Lorentz’s assumption as well as Einstein’s. If on account of that one considers this basic assumption refuted, then one would be forced to consider it a failure to attempt to base the entire field of physics, including electrodynamics and optics, upon the principle of relative movement.* "

In that same year, Planck took the highest velocity nine data points from Kaufmann's paper and reanalyzed them and found multiple mistakes. That led to many more measurements in various labs and by 1914 it was clear: the Einstein (Lorentz) interpretation of the change of mass with speed was confirmed and the alternatives were ruled out.

We've already talked about some of the classic tests of Special Relativity and today, it's a tool and not "just" a theory. Its combination with Quantum Mechanics has led to the most precise predictions and confirmations of those predictions in history.

And yet, Einstein's Nobel Prize ignored relativity.

The mass measurements weren't the end of problems for Special Relativity.

### "Jewish Science"

Anti-semitism was in the fabric of European life

> “As remarkable as Einstein’s papers are…it still seems to me that something almost unhealthy lies in this unconstruable and impossible to visualize dogma. An Englishman would hardly have given us this theory… the abstract conceptual character of the Semite expresses itself.” **Arnold Sommerfeld, Nobel Laureate**

This was the beginning of the attack on “Jewish Science” by the National Socialists Party in Germany..early 1930s

> “Materialistic natural science had eclipsed the “spiritual sciences,” giving rise to the “arrogant delusion“ that humankind can achieve the “mastery of nature…That influence has been strengthened by the all-corrupting foreign spirit permeating physics and mathematics…” **Philipp Lenard, Nobel Laureate**

> “The scientist does not exist only for himself or even for his science. Rather, in his work he must serve the nation first and foremost. For these reasons, the leading scientific positions in the National Socialist state are to be occupied not by elements alien to the Volk but only by nationally conscious German men.” **Johannes Stark, Nobel Laureate**

> “His theory is not the keystone of a development, but a declaration of total war, waged with the purpose of destroying what lies at the basis of this development, namely, the world view of German man . . . This theory could have blossomed and flourished nowhere else but in the soil of Marxism, whose scientific expression it is, in a manner analogous to that of cubism in the plastic arts and the unmelodies and unharmonic atonality in the music of the last several years [“degenerate science”!]. Thus, in its consequences the theory of relativity appears to be less a scientific than a political problem.” **Bruno Thüring**

> “The simple question that precedes every scientific enterprise is: who is it who wants to know something, who is it who wants to orient himself in the world around him? It follows necessarily that there can only be the science of a particular type of humanity and of a particular age. There is very likely a Nordic science, and a National Socialist science, which are bound to be opposed to the Liberal–Jewish science, which, indeed, is no longer fulfilling its function anywhere, but is in the process of nullifying itself.” **Adolf Hitler**

Eventually, it became unsafe for Einstein to remain in Germany and he emigrated to the United States in 1932.

Let's go paint a house in Bern.