einstein

history, together with the famous old professors who still believed in them. 69
As a result, Poincaré expressed a principle of relativity that contained certain similarities to Einstein’s, but it had a fundamental difference.
Poincaré retained the existence of the ether, and the speed of light was, for him, constant only when measured by those at rest to this presumed
ether’s frame of reference. 70
Even more surprising, and revealing, is the fact that Lorentz and Poincaré never were able to make Einstein’s leap even after they read his
paper. Lorentz still clung to the existence of the ether and its “at rest” frame of reference. In a lecture in 1913, which he reprinted in his 1920 book
The Relativity Principle, Lorentz said, “According to Einstein, it is meaningless to speak of motion relative to the ether. He likewise denies the
existence of absolute simultaneity. As far as this lecturer is concerned, he finds a certain satisfaction in the older interpretations, according to which
the ether possesses at least some substantiality, space and time can be sharply separated, and simultaneity without further specification can be
spoken of.” 71
For his part, Poincaré seems never to have fully understood Einstein’s breakthrough. Even in 1909, he was still insisting that relativity theory
required a third postulate, which was that “a body in motion suffers a deformation in the direction in which it was displaced.” In fact, the contraction
of rods is not, as Einstein showed, some separate hypothesis involving a real deformation, but rather the consequence of accepting Einstein’s
theory of relativity.
Until his death in 1912, Poincaré never fully gave up the concept of the ether or the notion of absolute rest. Instead, he spoke of the adoption of
“the principle of relativity according to Lorentz.” He never fully understood or accepted the basis of Einstein’s theory. “Poincaré stood steadfast and
held to his position that in the world of perceptions there was an absoluteness of simultaneity,” notes the science historian Arthur I. Miller. 72
His Partner
“How happy and proud I will be when the two of us together will have brought our work on the relative motion to a conclusion!” Einstein had written
his lover Mileva Mari back in 1901. 73 Now it had been brought to that conclusion, and Einstein was so exhausted when he finished a draft in June
that “his body buckled and he went to bed for two weeks,” while Mari “checked the article again and again.” 74
Then they did something unusual: they celebrated together. As soon as he finished all four of the papers that he had promised in his memorable
letter to Conrad Habicht, he sent his old colleague from the Olympia Academy another missive, this one a postcard signed by his wife as well. It
read in full: “Both of us, alas, dead drunk under the table.” 75
All of which raises a question more subtle and contentious than that posed by the influences of Lorentz and Poincaré: What was Mileva Mari ’s
role?
That August, they took a vacation together in Serbia to see her friends and family. While there, Mari was proud and also willing to accept part of
the credit. “Not long ago we finished a very significant work that will make my husband world famous,” she told her father, according to stories later
recorded there. Their relationship seemed restored, for the time being, and Einstein happily praised his wife’s help. “I need my wife,” he told her
friends in Serbia.“She solves all the mathematical problems for me.” 76
Some have contended that Mari was a full-fledged collaborator, and there was even a report, later discredited, 77 that an early draft version of his
relativity paper had her name on it as well. At a 1990 conference in New Orleans, the American Association for the Advancement of Science held a
panel on the issue at which Evan Walker, a physicist and cancer researcher from Maryland, debated John Stachel, the leader of the Einstein
Papers Project. Walker presented the various letters referring to “our work,” and Stachel replied that such phrases were clearly romantic politeness
and that there was “no evidence at all that she contributed any ideas of her own.”
The controversy, understandably, fascinated both scientists and the press. Columnist Ellen Goodman wrote a wry commentary in the Boston
Globe, in which she judiciously laid out the evidence, and the Economist did a story headlined “The Relative Importance of Mrs. Einstein.” Another
conference followed in 1994 at the University of Novi Sad, where organizer Professor Rastko Magli contended that it was time “to emphasize
Mileva’s merit in order to ensure a deserved place in the history of science for her.” The public discussion culminated with a PBS documentary,
Einstein’s Wife, in 2003, that was generally balanced, although it gave unwarranted credence to the report that her name had been on the original
manuscript. 78
From all the evidence, Mari was a sounding board, though not as important in that role as Besso. She also helped check his math, although
there is no evidence that she came up with any of the mathematical concepts. In addition, she encouraged him and (what at times was more
difficult) put up with him.
For both the sake of colorful history and the emotional resonance it would have, it would be fun if we could go even further than this. But instead,
we must follow the less exciting course of being confined to the evidence. None of their many letters, to each other or to friends, mentions a single
instance of an idea or creative concept relating to relativity that came from Mari .
Nor did she ever—even to her family and close friends while in the throes of their bitter divorce—claim to have made any substantive
contributions to Einstein’s theories. Her son Hans Albert, who remained devoted to her and lived with her during the divorce, gave his own version
that was reflected in a book by Peter Michelmore, and it seems to reflect what Mari told her son: “Mileva helped him solve certain mathematical
problems, but no one could assist with the creative work, the flow of ideas.” 79
There is, in fact, no need to exaggerate Mari ’s contributions in order to admire, honor, and sympathize with her as a pioneer. To give her credit
beyond what she ever claimed, says the science historian Gerald Holton, “only detracts both from her real and significant place in history and from
the tragic unfulfillment of her early hopes and promise.”
Einstein admired the pluck and courage of a feisty female physicist who had emerged from a land where women were generally not allowed to
go into that field. Nowadays, when the same issues still reverberate across a century of time, the courage that Mari displayed by entering and
competing in the male-dominated world of physics and math is what should earn her an admired spot in the annals of scientific history. This she
deserves without inflating the importance of her collaboration on the special theory of relativity. 80
The E=mc 2 Coda, September 1905
Einstein had raised the curtain on his miracle year in his letter to his Olympia Academy mate Conrad Habicht, and he celebrated its climax with