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He was one of the greatest scientists the world has ever known, yet if I
had to convey the essence of Albert Einstein in a single word, I would choose
simplicity. Perhaps an anecdote will help. Once, caught in a downpour, he took
off his hat and held it under his coat. Asked why, he explained, with admirable
logic, that the rain would damage the hat, but his hair would be none the worse
for its wetting. This knack for going instinctively to the heart of a matter was
the secret of his major scientific discoveries -- this and his extraordinary
feeling for beauty.
I first met Albert Einstein in 1935, at the famous Institute for Advanced
Study in Princeton, N. J. He had been among the first to be invited to the
Institute, and was offered carte blanche as to salary. To the director’s dismay,
Einstein asked for an impossible sum: It was far too small. The director had to
plead with him to accept a larger salary.
I was in awe of Einstein, and hesitated before approaching him about some
ideas I had been working on. When I finally knocked on his door, a gentle voice
said, “Come” — with a rising inflection that made the single word both a welcome
and a question. I entered his office and found him seated at a table,
calculating and smoking his pipe. Dressed in ill-fitting clothes, his hair
characteristically awry, he smiled a warm welcome. His utter naturalness at once
set me at ease.
As I began to explain my ideas, he asked me to write the equations on the
blackboard so he could see how they developed. Then came the staggering— and
altogether endearing— request: “Please go slowly. I do not understand things
quickly.” This from Einstein! He said it gently, and I laughed. From then on,
all vestiges of fear were gone.
Einstein was born in 1879 in the German city of Ulm. He had been no infant
prodigy; indeed, he was so late in learning to speak that his parents feared he
was a dullard. In school, though his teachers saw no special talent in him, the
signs were already there. He taught himself calculus, for example, and his
teachers seemed a little afraid of him because he asked questions they could not
answer. At the age of 16, he asked himself whether a light wave would seem
stationary if one ran abreast of it. From that innocent question would arise,
ten years later, his theory of relativity.
Einstein failed his entrance examinations at the Swiss Federal Polytechnic
School, in Zurich, but was admitted a year later. There he went beyond his
regular work to study the masterworks of physics on his own. Rejected when he
applied for academic positions, he ultimately found work, in 1902, as a patent
examiner in Berne, and there in 1905 his genius burst into fabulous flower.
Among the extraordinary things he produced in that memorable year were his
theory of relativity, with its famous offshoot, E=mc (energy equals mass times
the speed of light squared), and his quantum theory of light. These two theories
were not only revolutionary, but seemingly contradictory: The former was
intimately linked to the theory that light consists of waves, while the latter
said it consists somehow of particles. Yet this unknown young man boldly
proposed both at once—and he was right in both cases, though how he could have
been is far too complex a story to tell here.
Collaborating with Einstein was an unforgettable experience. In 1937, the
Polish physicist Leopold Infeld and I asked if we could work with him. He was
pleased with the proposal, since he had an idea about gravitation waiting to be
worked out in detail. Thus we got to know not merely the man and the friend, but
also the professional.
The intensity and depth of his concentration were fantastic. When battling
a recalcitrant problem, he worried it as an animal worries its prey. Often, when
we found ourselves up against a seemingly insuperable difficulty, he would stand
up, put his pipe on the table, and say in his quaint English, “I will a little
tink” (he could not pronounce “th”). Then he would pace up and down, twirling a
lock of his long, graying hair around his fore-finger.
A dreamy, faraway and yet inward look would come over his face. There was
no appearance of concentration, no furrowing of the brow -- only a placid inner
communion. The minutes would pass, and then suddenly Einstein would stop pacing
as his face relaxed into a gentle smile. He had found the solution to the
problem. Sometimes it was so simple that Infeld and I could have kicked
ourselves for not having thought of it. But the magic had been performed
invisibly in the depths of Einstein’s mind, by a process we could not
fathom.
When his wife died he was deeply shaken, but insisted that now more than
ever was the time to be working hard. I remember going to his house to work with
him during that sad time. His face was haggard and grief-lined, but he put forth
a great effort to concentrate. To help him, I steered the discussion away from
routine matters into more difficult theoretical problems, and Einstein gradually
became absorbed in the discussion. We kept at it for some two hours, and at the
end his eyes were no longer sad. As I left, he thanked me with moving sincerity.
“It was a fun,” he said. He had had a moment of surcease from grief, and then
groping words expressed a deep emotion.
Although Einstein felt no need for religious ritual and belonged to no
formal religious ritual and belonged to no formal religious group, he was the
most deeply religious man I have known. He once said to me, “Ideas come from
God,” and one could hear the capital “G” in the reverence with which he
pronounced the word. On the marble fireplace in the mathematics building at
Princeton University is carved, in the original German, what one might call his
scientific credo: “God is subtle, but he is not malicious.” By this Einstein
meant that scientists could expect to find their task difficult, but not
hopeless: The Universe was a Universe of law, and God was not confusing us with
deliberate paradoxes and contradictions.
Einstein was a accomplished amateur musician. We used to play duets, he on
the violin, I at the piano. One day he surprised me by saying Mozart was the
greatest composer of all. Beethoven “created” his music, but the music of Mozart
was of such purity and beauty one felt he had merely “found” it -- that it had
always existed as part of the inner beauty of the Universe, waiting to be
revealed.
It was this very Mozartean simplicity that most characterized Einstein’s
methods. His 1905 theory of relativity, for example, was built on just two
simple assumptions. One is the so-called principle of relativity, which means,
roughly speaking, that we cannot tell whether we are at rest or moving smoothly.
The other assumption is that the speed of light is the same no matter what the
speed of the object that produces it. You can see how reasonable this is if you
think of agitating a stick in a lake to create waves. Whether you wiggle the
stick from a stationary pier, or from a rushing speedboat, the waves, once
generated, are on their own, and their speed has nothing to do with that of the
stick..
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发表于 2016-7-10 16:39:36