The Man Who Stalked Einstein (7 page)

The postulates of theoretical physics had put the believers in ether under the gun
to demonstrate its presence. During 1910 and 1911, Lenard designed new experiments
based on equations developed by his collaborator, the Norwegian Vilhelm Bjerknes,
and set Laub to work. Lenard pushed the disbelieving Laub hard to uncover some expression
of ether’s presence. It was to no avail. If ether actually existed, it was proving
itself a worthy quarry for even as dedicated a hunter as Philipp Lenard. Einstein
witnessed the growing tension between Lenard and Laub from afar, his correspondence
with the young scientist a window onto the dark side of a man he had admired.

Lenard’s disappointment with Laub’s failure to prove the existence of ether was palpable.
Unwilling to consider the possibility that he might be wrong, Lenard instead blamed
the poor outcome of the experiments on Laub. He wrote a letter to Bjerknes in February
1911, which cited Laub’s disagreement with the principles of the research he’d been
assigned to conduct. “I have arranged these things for Herr Laub with great zeal.
He is, however, forever so captivated with the principle of relativity that I always
dread that he cannot be correct.”

As they had with Einstein, the events of Lenard’s personal life intruded upon his
absorption with his work. His son, Werner, had been a sickly child and continued to
incur health problems into adolescence. His illness excluded Werner from participating
in military service during the Great War, a crushing blow for an arch-nationalist
like Lenard. Lenard’s view of the pathophysiology affecting his son was that he “suffers
from the narrow-minded school teaching that ignores the individual and from the bad
nutrition during the war.” At the same time, his daughter, Ruth, was maturing and
had an academic bent. Against the fierce resistance of her father, she secretly qualified
for university admittance to study history and languages with the goal of becoming
a teacher.

Ultimately, Lenard and Einstein’s relationship was doomed not only by their scientific
differences but also by their personal ones. Lenard’s initial pleasure at Einstein
crediting him as an inspiration for his work on the photoelectric effect morphed into
a much more negative assessment. Beginning in 1915, with Einstein’s first publications
related to what would become his theory of general relativity, Einstein broadened
his concepts to apply to not only bodies in a steady state, as in his theory of special
relativity, but all physical circumstances. He chose as an experimentally provable
example of the power of his theory an explanation of the perihelion of the planet
Mercury, wherein, contrary to Kepler’s law, the point in the orbit of Mercury closest
to the sun changes from orbit to orbit.

Einstein’s critics went on the attack. In 1917, Ernst Gehrcke, an ardent anti-relativity
scientist—and someone who would be linked to Lenard’s future efforts to discredit
Einstein—republished in the
Annalen der Physik
a 1902 work by a physicist named Paul Gerber. Gerber had devised a formula for explaining
the perihelion phenomenon that did not require reference to relativity. Bringing to
light the Gerber publication gave Gehrcke the chance to raise the possibility that
Einstein had plagiarized Gerber’s ideas. He attacked both Einstein’s primacy and his
integrity in a single blow. It would be the first of a stream of accusations by Einstein’s
critics—including Lenard’s claim that Einstein had cribbed the work of the obscure
Austrian physicist, Friedrich Hasenoehrl—that Einstein was fundamentally a plagiarist.

As evidenced by a letter that Lenard wrote to Johannes Stark, then the editor of
the omnibus publication
Almanac of Radioactivity and Electronics
, Lenard was in league with Gehrcke: “I would like to ask whether a short original
post by me . . . on ether and gravitation . . . could be quickly published in the
Almanac,” Lenard wrote following Gehrcke’s republication of Gerber’s article.

Stark responded, “I will gladly include your study on ether and gravitation in my
edited almanac. . . . I find it meritorious that you have co-contributed to the acceptance
of Gerber’s work.” In what was certainly a direct reference to Einstein’s theory of
general relativity, Stark continued, “The work is physically well thought and is,
for me, more likable than so many of the theoretical works, which, with a sort of
dialectical sorcery, pretend to solve the difficult physical problems.”

Lenard immediately thanked him for agreeing to publish his commentary, which was
intended to accomplish several goals: reinforce the rationale for belief in ether;
set to right the infringement by Einstein on Gerber’s ideas; establish the failings
of the theory of general relativity; and, in Lenard’s words, make clear that “the
ether explanation of gravitation [believed at the time to act as a radiomagnetic wave]
. . . appears good to me because it is so simple that by it alone, everything works.”

Unfortunately for Lenard, events conspired to put him on the defensive. The very
next issue of the
Annalen der Physik
contained scathing reviews of the Gerber article by well-respected astronomers Hugo
von Seeliger and a close friend of Einstein’s, Max von Laue. Lenard had to choose
to either dispute their arguments or withdraw the most serious of his concerns about
Einstein. Because, at the time, he was otherwise occupied with scientific and administrative
issues related to the Institute, he chose the latter approach and provided Stark with
a replacement commentary for the
Almanac
. Interestingly, this revised version was accepting of Einstein’s theory of special
relativity and even of much of his theory of general relativity. However, Lenard believed
that “[t]he principle must give up its universality and no longer claim relativity
of all movements but restrict itself to those movements which proceed under the influence
of mass proportional forces, as is gravitation.”

Given their history of mutual encouragement, Einstein must have wondered about Lenard’s
assault. He retaliated by publishing in
Naturwissenschaften
“Dialog on the Objections against the Theory of Relativity,” a courtly and creative
exchange of views pitting the arguments of a hypothetical “Critic” against the defense
of a “Relativist.” The fictional debate is stylized and civil, beginning with the
apologetic tone of the Critic, and directly references Gehrcke’s charges of plagiarism:

Critic
: So as not to upset you too much, and possibly even make you undertake this business
(which you can’t avoid anyway) with a certain pleasure, I will say this in comfort.
Unlike many of my colleagues, I am not so full with the status of my guild so as to
make me act as a superior being with superhuman insight and certainty (like newspaper
journalists about scientific literature, or playwright-critics). . . . Also I have
no wish to—as was lately done by one of my colleagues—jump on you like a district-attorney
and accuse you of theft of intellectual property, or accuse you of equally dishonorable
acts.

There follows an extended interchange between the Critic and the Relativist on such
issues as the relationship between very high speeds and the slowing of the passage
of time; the different possible perspectives for considering the effects of rapid
deceleration; and the perihelion of Mercury. These vignettes afforded Einstein the
opportunity to explain certain misconceptions about relativity. In the special world
that Einstein creates, the Critic concedes the logic of relativity but with some reservations.

Critic
: After your last statements it does seem to me that no self-contradiction of the
theory of relativity can be deduced. . . . Indeed, it now seems not unlikely to me
that the theory is free from self-contradiction altogether, but it does not in itself
mean that the theory should be considered in earnest.

Particularly with regard to the perihelion of Mercury, Einstein argues for the plausibility
of his theory rather than its correctness and calls out Lenard’s objections:

Relativist
: The secular perihelion motion of the planet Mercury had to be clarified. This perihelion
motion was certainly noticed by astronomers, and they were unsuccessful in finding
an explanation on the basis of the Newtonian theory. . . . In asserting the equality
of coordinate systems as a matter of principle it is not said that every coordinate
system is equally convenient for examining a certain physical system. . . . However
as a matter of principle such a theory of relativity is equally valid as any other.

The Critic is convinced to the extent of the specific examples that Einstein has discussed.
However, he cannot help himself. He must ask one more question. At this point, it
appears that Einstein is speaking for Lenard as he wishes Lenard might speak:

Critic
: After this conversation I have to admit that the refutation of your point of view
is not as easy as it seemed to me earlier. I do have more objections up my sleeve.
But before pestering you with that I want to think over our present conversation thoroughly.
. . . I ask out of pure curiosity: how does the diseased man of theoretical physics
fare, the ether, that many of you have declared to be definitely dead?

Relativist
: If there would be an ether, then in each space-time point there would have to be
a particular state of motion, that would have to play a part in optics. There is no
such privileged state of motion, as has been taught to us by the special theory of
relativity, and that is why there is no ether in the old sense . . . space without
matter and without electromagnetic field seems to be characterized as absolutely empty.
. . . One can quite well construe this circumstance in such a way that one speaks
of an ether, whose state of being is different from point to point. Only one must
take care not to attribute to this ether properties similar to properties of matter.

Lenard fought back in 1918, writing a new version of an earlier article,
On the Principle of Relativity, Ether, and Gravitation
, as a free-standing publication. Unlike the compliant hypothetical critic in Einstein’s
article, Lenard is anything but agreeable. There is a hard edge to his writing. “What
Mr. Einstein carried out as ‘a relativist’ . . . was and is not convincing to me.
He touches on certain principal points too little or not at all.”

The fundamental difference between the two men is that Einstein made the claim for
all reference systems being equally plausible (e.g., his example where the train or
the station could serve equally well as the reference point), while Lenard favored
using “simple, sound common sense” to favor one reference system over another. This
complaint—that the application of Einstein’s theory of relativity lacked common sense—would
become a long-lasting theme for Lenard and other Einstein critics.

This exchange marked the end of Lenard’s and Einstein’s discourse until their very
public confrontations in Berlin and Bad Nauheim of 1920. Secular events took precedence.
World War I concluded hostilities in November 1918. The Kaiser abdicated, ending centuries
of monarchic rule. The weak republic that filled the ensuing vacuum in governance
was marked from the start. The Allies’ demand for reparations led to rampant unemployment
and poverty across Germany. A deadly struggle developed between nationalist right-wing
extremists and worker-backed, socialist, and communist interests. The days were filled
with angst, anger, and violence, while the nights were devoted to hedonistic gaiety
that signaled a sense of there being no tomorrow.

Meanwhile, Einstein persevered. He cemented growing support among natural scientists
for his theory of relativity. Measurements made during a 1919 solar eclipse confirmed
the accuracy of a prediction of the theory of general relativity, giving new credence
to Einstein’s theory and making him an unlikely international celebrity. In the same
year, soon after his divorce from Mileva was final, he married Elsa. It was to become
a marriage of convenience in which both Elsa and Einstein accepted their shares of
a tacit bargain.

Elsa lived the life of a spouse of a famous man, reveling in the travel, social status,
and comfort her marriage afforded her. Einstein could focus on his work, secure in
the knowledge that Elsa would handle the details of his daily life while allowing
him the freedom to seek romance in sleeker, more ardent arms. His letters reveal that
he took several lovers during his marriage and that, at least on some occasions, he
discussed his relationships with Elsa. Writing to Elsa of one paramour, socialite
Ethel Michanowski, he noted,

Mrs. M definitely acted according to the best Christian-Jewish ethics: 1) one should
do what one enjoys and what won’t harm anyone else; and 2) one should refrain from
doing things one does not take delight in and which annoy another person. Because
of 1) she came with me, and because of 2) she didn’t tell you a word. Isn’t that irreproachable?

Soon after the end of the war, Lenard further tightened his grip on every aspect of
his institute, becoming more remote in his dealings with the students and his subordinates.
He mourned the death of his only son. “He was not given the privilege to take part
in the war. . . . With him, the last bearer of my name left the earth.” Lenard grew
more radical. He became a believer in the widespread but outrageous notion that the
German army had not been defeated in battle but had been “stabbed in the back” by
the pacifists, republicans, and Jews who had sued for peace. Passages from his autobiography
detailing this period provide early evidence of his developing anti-Semitism.

When the army returned after four years, not defeated in combat, they found a spiritually
decimated patrimony. . . . The pseudo-blossoming that was to be observed soon at center
stage of the relativity theory and the sudden increase in scientific journals could
not have been comprehended if not even uninitiated people had increasingly understood
who the real victors of the great war had been: the Jews in their now free unfolding
of their own spirit.