Einstein (26 page)

Against this the French scientists, in so far as they participated in the war of words, asserted that the “thoroughness” of German science consists in a pedantic collection of unimportant facts, and its “philosophical” character in the production of a smoke screen that obscures the true relation between things. The Anglo-Saxon scientists preferred to point out that German science emphasizes “idealistic” principles so as to make it easier to excuse particularly inhuman acts; for if one must commit atrocities in order to carry out such principles, then they are “idealistically” justified.

These arguments soon made their appearance in the controversy over the relativity theory. By using arguments of this kind it could be attacked by the one party as a particularly “German” theory and by the opposing side as particularly “un-German.” We shall see that in this way Einstein’s theories, which at first sight appear far removed from any political utility, were soon drawn into the struggles of nations and parties.

During the war the newspapers in Berlin were filled with the battles and victories of the German army. The people were filled with joy and occupied themselves with discussions of such questions as which of the conquered territories should be kept by Germany after the war, whether Poland should actually be freed or become a German protectorate, and so forth. They counted the number of English merchant ships sunk by their submarines, and many of them kept lists of the amount of tonnage sent to the bottom of the sea. Every day they copied the figures from the newspapers and conscientiously added up the totals like a business man making up his annual accounts. To their astonishment they soon found that the total exceeded all the tonnage England ever had, and they began to wonder that there were still any English ships on the sea.

In private life, however, the pre-eminent interest of everybody was in obtaining food. Whoever managed a household had to be as cunning and ingenious as possible to get any of the food that occasionally appeared on the market; and to prepare it in a halfway palatable manner, since it was often of an unusual nature.

Einstein’s health was often poor during the war, and he was happy to be connected with a family with whom he could eat home-cooked meals instead of having to depend on restaurant fare, whose cooking at this time was based on the hygienic instructions of the military authorities. Some of Einstein’s well-to-do relatives had previously looked upon him as the black sheep of the family. His running away from the gymnasium in Munich, his devotion to studies that could not bring him a good income, and his marriage to a woman completely outside their circle had not met their approval. It was therefore with great astonishment that they had heard of his growing fame. When Einstein was called to Berlin and made a member of the Royal Prussian Academy, they felt honored to have him at their homes and to be mentioned as his relatives. Einstein accepted this situation good-humoredly.

In his uncle’s house Einstein again met his cousin Elsa, with whom he had been friends as children in Munich. She was now a widow with two daughters, a woman of friendly, maternal temperament, fond of amusing conversation, and interested in
creating a pleasant home and preparing the scanty wartime meals as best she could. Einstein often went to their house, and found a new family life there.

Frau Elsa could not study the works of great physicists with him as Mileva Maritsch had done at Zurich. She had a happy outlook on life, and not the harsh, self-denying nature of the Slavic student. Regarding Einstein as a physicist, she knew only that he had now become a famous man whom the outstanding scientists of the Prussian Academy, the University of Berlin, and foreign countries recognized as their equal and often as their superior. To have such a relative and friend was a source of pride and joy to her and she wanted to relieve him of the cares of daily life. Einstein, who valued friendliness, often made himself useful in her house by practicing “applied physics.”

When I visited Berlin on one occasion during the war, Einstein invited me to his uncle’s house for dinner. I declined at first, saying: “Right now when everything is so scarce no one likes to have an unexpected guest.” Thereupon Einstein replied in his sincere manner, which sounded like the simplicity of a child but which could equally well be regarded as acid criticism: “You need have no scruples. On the contrary, my uncle has more food than the per capita average of the population. If you eat at his table you are serving the cause of social justice.” There I met his cousin Elsa for the first time. She said to me half playfully, half in earnest: “I know very well what a talented physicist our Albertle is. In these times we have to buy food in all kinds of cans which no one knows how to open. Often they are of unfamiliar, foreign make, rusted, bent, and without the key necessary to open them. But there hasn’t been a single one yet that our Albertle has not been able to open.”

While the war was still going on, Einstein married his cousin Elsa. He, who had always had something of the bohemian in him, began to lead a middle-class life. Or, to put it more exactly, Einstein began to live in a household such as was typical of a well-to-do Berlin family. He lived in a spacious apartment in the so-called “Bavarian quarter.” This section had nothing Bavarian about it except that the streets were generally named after Bavarian cities. He lived in the midst of beautiful furniture, carpets, and pictures; his meals were prepared and eaten at regular times. Guests were invited. But when one entered this home, one found that Einstein still remained a “foreigner” in such a surrounding — a bohemian guest in a middle-class home.

Elsa Einstein had many of the characteristics of the people of
her native Swabia. She valued greatly what was known in Germany and especially in Swabia as
“Gemütlichkeit.”
It is no wonder that she was very happy when she saw the esteem and admiration in which her husband was held and which she shared as his wife. Nevertheless, there were always two sides to the job of being the wife of a famous man. The people about her were always inclined to look very critically at her and, as a compensation for the respect that they reluctantly paid her husband, to unload upon her all the reproaches they would have liked to bring against him.

When Elsa Einstein was discussed in professional circles in Berlin, one could hear all sorts of criticism of this nature. The most harmless was probably the assertion that her intellectual capacities hardly fitted her to be Einstein’s wife. But if Einstein had followed this criticism, what woman could he have married? The question was, rather, could she create tolerable living conditions for Einstein in which he could carry on his work? And in considerable measure she did so. There is no ideal solution to this problem, and since Einstein believed less than most men in the possibility of an ideal solution, he did not feel hurt when his wife did not completely represent this ideal.

Some professors complained that because of her it was difficult for physicists to gain access to Einstein. She preferred, they claimed, to have Einstein meet writers, artists, or politicians, because she understood these people better and considered them more valuable. Einstein, however, was certainly not the man to be easily influenced in the choice of his company. He himself liked to mingle with all kinds of people and did not restrict himself to professional circles. It may sometimes have happened that a visitor whom Einstein did not wish to see put the blame on Einstein’s wife because he did not want to admit to himself that his company was not so interesting for Einstein as he himself thought it ought to be.

Others complained that Mrs. Einstein placed too much value on the external symbols of fame and did not really know how to value her husband’s inner greatness. It is obvious, however, that the wife of a great man can understand most easily the effect of his activities on public opinion, and that this will consequently interest her more than anything else.

Any woman in Elsa Einstein’s position would probably have acted more or less as she did. The only difference was that the public is rarely so much interested in the life of a scientist as it was in Einstein’s. On this account his wife was blamed for various
things that are actually common occurrences. The married life of a great man has always been a difficult problem, no matter how he or his wife is constituted. Nietzsche once said: “A married philosopher, is to put it bluntly, a ridiculous figure.”

Einstein was protected against various difficulties by the circumstance that he always kept a certain part of his inner self from any contact with others, and that he had no desire to share his inner life completely with anyone. He was very much aware that every happiness has its shadows, and accepted this fact without protest.

When in 1932 some women’s clubs opposed Einstein’s entry into the United States because in their opinion he spread subversive doctrines, e.g., pacifism, Einstein remarked jokingly to a representative of the Associated Press: “Why should one admit a man who is so vulgar as to oppose every war except the inevitable one with his own wife?”

And on another occasion he made a remark based on many years of experience: “When women are in their homes, they are attached to their furniture. They run around it all day long and are always fussing with it. But when I am with a woman on a journey, I am the only piece of furniture that she has available, and she cannot refrain from moving around me all day long and improving something about me.”

This lack of any illusion about the possibility of happiness in life has saved Einstein from the mistake made by many a husband who looks upon all the defects that are characteristic of life itself as defects in his wife and in consequence plays the stern judge with her instead of remembering her good qualities and accepting her bad ones as a necessity of nature.

During this period Einstein’s first wife and his two sons lived in Switzerland. This circumstance caused Einstein a great deal of financial worry because of the great difficulty in transferring money from Germany to Switzerland and the rate of exchange, which became more and more unfavorable as the war progressed. But since her student days Mileva Maritsch was so attached to her life in Switzerland that on no account would she live in Germany.

The war and the psychological conditions produced by it in the world of science did not prevent Einstein from devoting himself with the greatest intensity to improving his theory of gravitation. Working along the line of his ideas that he had found in Prague and Zurich, he succeeded in 1916 in developing a completely independent, logically unified theory of gravitation. Einstein’s conception differed fundamentally from that of Newton, and a real understanding of his theory requires a wide knowledge of mathematical methods. Without using any mathematical formulæ, I shall here attempt to present the fundamental ideas in so far as they are necessary for our understanding of Einstein’s personality and the influence of his theory on his period and environment.

The great difficulty involved in explaining Einstein’s new theory lies in the fact that it does not arise from any slight modification of Newtonian mechanics. It bursts asunder the entire framework within which Newton attempted to comprehend all phenomena of motion. The familiar concepts of “force,” “acceleration,” “absolute space,” and so on have no place in Einstein’s theory. Even to the average physicist the principles composing Newtonian mechanics seem either to be proved by experience or by reasoning, and it is hardly possible for him to comprehend any change in a structure that he has come to regard as immutable. This is an illusion that must be destroyed in order to be able to understand Einstein’s theory.

According to Newton’s law of inertia, a body not acted on by any force moves in a straight line with constant velocity. This is true no matter what is the mass or other physical properties of the body involved. Hence it may be stated that its motion can be described “geometrically.” On the other hand, if any force acts on the body, then, according to Newton’s law of force, it experiences acceleration inversely proportional to its mass. Consequently, particles with different masses perform different
paths under the action of the same force. Motion under force can only be described by using a non-geometrical term
mass
.

We have seen in
Section 8
of
Chapter IV
, however, that in his gravitational theory of 1911 Einstein had noted that the force of gravity has the unique property that its influence is independent of the mass of the body on which it acts. And as a consequence he had concluded that the presence of a gravitational field of force cannot be distinguished from the result of accelerated motion of the laboratory. This means that not only motion under no force, but also motion under gravitational force alone can be described purely geometrically, if these forces are parallel and of equal magnitude in the whole region considered.

With this foundation, the problem that now faced Einstein was this: What is the geometrical form of the path which a body in a gravitational field describes relative to any laboratory?

Einstein’s solution of this problem is based on a concept that the laws of geometry in a space where there exists gravitational field are different from those in a space which is “free of forces” in the old sense. This was an idea so novel that the physicists and mathematicians used to nineteenth-century physics were bewildered by it. In order to understand what Einstein meant, we must go back to the positivistic conception of science, and in particular to the ideas of Henri Poincaré described in
Section 9
of
Chapter II
. According to this view, the truth of mathematical propositions concerning points, straight lines, and so forth can only be verified in our world of experience when these mathematical notions are defined in terms of physical operations. We must give what P. W. Bridgman calls the “operational definitions” to the geometrical terms. For example, we must define “straight lines” in terms of certain steel rods prepared according to a specified method, and if we make a triangle with these rods we can verify by actual measurement on this triangle whether the angles add up to two right angles or not.