Science: Einstein in English

One and a half million words was the estimated output of some 3,000 members of the American Association for the Advancement of Science and associated groups who met last week in Pittsburgh. They read and discussed 1,200 papers on subjects ranging from the folklore of Schoharie County, N. Y., to sarcomatous changes in mammary adenomas. Many an industrial and academic research laboratory had exhibits. Harold Clayton Urey, newest U. S. Nobel Laureate, was there. When the apparatus for making heavy water broke down he fixed it. Nobelman Robert Andrews Millikan was ‘there to talk about cosmic rays, show the latest apparatus for research in artificial radioactivity. On hand was many another bigwig. But the name on everyone’s tongue was that of Albert Einstein. The great German journeyed from the Institute for Advanced Study at Princeton to make his first formal discourse in English.

Sessions and exhibits were staged in the new Mellon Institute of Industrial Research building, a vast, square, $4,000,000 structure. Dr. Einstein would have none of that. He said he would address a small audience in a small place. The American Mathematical Society and the American Physical Society arranged his lecture for Carnegie Institute of Technology’s Little Theatre, seating 400, then nearly came to blows over distribution of tickets. Five thousand pleas for admission poured in. Said Dr. Einstein gently: “Bah! I will speak to 400—no more. No more would understand.” His subject: “A Simple Proof of the Equivalence of Mass and Energy.”

As curtain time drew near photographers mounted the stage to snap the packed, hand-picked audience. Some went backstage to get Einstein pictures. Outside six policemen held back a surging crowd of curious. The curtain went up on a stage empty but for a blackboard covered with equations chalked in different colors. Applause began. In the midst of it Dr. Einstein ambled from the wings, his halo of white hair glowing in the dim light.

“This is simple—not new,” he said. “For 30 years is known mass and energy is equivalent. I hope you pardon because it is so simple.”

Words followed words. “Four dimension vector . . direct from Lorentz transformation . . . sum of impulses before and after collision . . . relative to all systems of coordinates. . . .” Sometimes the speaker lapsed into German, once or twice asked his hearers to translate a German technical word.

It was in 1905 that Einstein laid down his famed equation for interconversion of mass and energy: E = MC², where E is energy, M mass, C the velocity of light. Since then experimental physicists have converted matter into radiation and radiation into matter. In 1919 the fact that radiant energy responds to gravitation as matter does was demonstrated by the bending of starlight on passing around the sun. And, according to the theory, not only radiant energy but energy of motion had mass. Thus a steamship or cannon ball weighed infinitesimally more when moving than at rest.

Last week Dr. Einstein derived the same old equation, E = MC², without using the Maxwell electromagnetic equations as he did originally. First he showed how four-dimensional Relativistic equations were derived from ordinary three-dimensional equations by means of a mathematical bridge called a Lorentz transformation. Then he applied the four-dimensional equations to inelastic collisions between particles. Such particles do not bounce but stop dead at contact, and therefore lose the extra mass represented by their energies of motion. But with the change of mass there is a change of energy, and, as the blackboard showed at the end of an hour, the two are precisely equal. When the lecture was over a newshawk scuttled up to the blackboard, seized the piece of chalk which Dr. Einstein had laid down, carried it off proudly as a trophy.

Before the lecture a group of reporters went to interview Dr. Einstein at the home of his host, Nathaniel Spear, Pittsburgh furniture tycoon. They found him sitting at ease by a gas-log fire, not nearly so nonplused and frightened by the U. S. Press as he was four years ago. He understood the questions perfectly, groped now and then for an English word or phrase but seldom for a reply. Mr. Spear, confined to bed upstairs, sent down a request that the eminent man should pose for photographs beside a bust of Socrates in the parlor.

“Ach, nein,” said Dr. Einstein.

Some of the newshawks who remembered that Einstein’s original universe was closed, curved and finite were startled when he said he was no longer sure of this. But there was no particular reason for excitement on this score. Following the General Theory of Relativity (1915) Einstein erected a cosmos whose radius turned out to be 32,000,000,000 light years. But Willem de Sitter worked out a universe in which space itself was expanding independently of its matter and Hubble & Humason at Mount Wilson confirmed this expanding universe theory by actual observations. Thus Einstein’s universe fell into general disfavor, without at all impairing the General Theory of Relativity. Four years ago Einstein accordingly revised his original universe to conform with these observations.

Said a newshawk: “Do you like to talk about other things than Science?”

“Yes,” smiled Herr Doktor, “but not to you.”