21-27 Oct

Q: Why isn't the night sky bright?

ABSTRACT

There are a great many unsolved problems in science, in life, and in our understanding of the Torah. Yet, like our father Abraham rushing to the binding of his son, we must go forward with complete confidence in the ultimate clarification.

A: About 150 years ago, Olbers asked, "Why isn't the night sky bright?" If the stars are uniformly distributed, we can draw shells of constant thickness at varying radii from the Earth. Then the number of stars in each shell should increase as the square of the distance from the Earth. The intensity of light from the each star falls off as the square of the distance. Thus the amount of light received from each shell remains constant. Since there is no limit to the number of shells, the amount of light by night (and by day, too) should be infinite. One of the explanations of this paradox is that the number of stars at large distances from us is greatly reduced because of the finite lifetime of stars. Our astronomical observations may be interpreted as indicating that stars are continually being formed as well as destroyed. This fits in remarkably with the phrase in our daily prayers: "Who in His goodness renews the work of creation every day" as is stated in Psalms: "Who makes the great light" (present tense).

BIO
Born in Elizabeth, New Jersey, Alvin Radkowsky attended Yeshiva University, CCNY, George Washington University, and Catholic University, where he completed his doctorate in physics. From 1948 to 1972 he served as chief scientist of the Naval Nuclear Propulsion Project. In this capacity he helped Admiral Hyman Rickover design the first nuclear submarine and invented a prize-winning method for prolonging the life span of nuclear reactors. During this time Radkowsky was active in the orthodox synagogue and Talmud study group in Summit Hill, Maryland. He is a Fellow of the American Physical Society and of the American Nuclear Society and a Member of the US National Academy of Engineering.

In 1972 Radkowsky made aliya with his wife and daughter and became a professor of nuclear engineering at Tel Aviv and Ben-Gurion universities. His major project is a design for a nuclear reactor which does not produce plutonium and nuclear waste.

CLICK HERE TO ORDER

B’OR HA’TORAH  is Published by SHAMIR
Professor Herman Branover, Editor-in-Chief