Friday September 19, 2014
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03-047 The Phenomenon of Albert Einstein III

Friday Sep 19, 2014

Lead: The theories of Albert Einstein helped shape the modern understanding of the universe. One of the most interesting ideas growing out of his work was the clock theory.

Tag: A Moment in Time with Dan Roberts.

Content: Writing in the early decades of the twentieth century, Einstein, as part of his theory of relativity, advanced the idea that time does not run at the same pace for every observer. If a person holding a clock is riding a train, the clock will run a tiny bit slower than a similar clock held by his companion who is standing still beside the track. The difference is caused by the speed of the train. The phenomenon can also be caused by gravity. A clock on the sun - with its stronger gravity - would not run quite as fast as a clock on the Earth.

The implications of Einstein's theory are particularly important for travel in space. A clock in a rocket speeding through space would operate slower than a similar one on the earth. An astronaut riding on that spaceship would not notice the clock's slowdown because her body processes would have slowed down at the same rate. When she returned from a long space voyage she would find that she was much younger in appearance and physical condition than her twin sister left behind on earth.

L.R. Shepherd a British physicist calculated that if a crew could crank up their spaceship to just under the speed of light, 186,000 miles per second, they could get to the star Procyon (Pro-cee-on)(10.4 light years away). When they got back they would have aged three years. Those who sent them on the mission would be twenty-one years older.

Science fiction writers and movie makers solve the problem of traveling vast distances between planets, stars, and galaxies by having their characters leap into hyperspace or a fourth dimension, or accelerating into warp drive, but for now those inhabiting this part of the Milky Way who look into the heavens must be content to live at least for the time being within the confines of the universe as described by Albert Einstein.

In Richmond, Virginia, this is Dan Roberts.


Bronowski, J. "The Clock Paradox,"

Crelinsten, Jeffrey. "Einstein, Relativity, and the Press: The Myth of Incomprehensibility," The Physics Teacher (February, 1980): 115-122.

Dyson, Freeman J. "Will Man Survive in the Cosmos?," Outposts.

Missner, Marshall. "Why Einstein Became Famous in America," Social Studies of Science 15 (1985): 267-291.

Rosenfeld, Albert. "A Three Million Year Trip in Fifty-Five Years," Life (May 24, 1963): 35-37.

Westin, R. Barry. "American Response to the Concept of Time in Relativity Theory with Particular Attention to the Twins Paradox," unpublished essay, August 3, 1988.

Copyright 2014 by Dan Roberts Enterprises, Inc.


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