Alfred Scharff Goldhaber
C.N. Yang Institute for Theoretical Physics; State University of New York
In the column "Zero Gravity" (APS News, February 2000) the CAUTION: the mass of this product contains the energy equivalent of 85 million tons of TNT per net ounce of weight. Thanks to relativity and the equivalence of inertial and gravitational masses the statement is correct, assuming the TNT and product are at the same place. Mass might be a better choice so that the caution would apply even if the product were on the moon and the TNT in outer space.
Martin L. Sage
Department of Chemistry; Syracuse University
Newt Gingrich's "Scientists Must Speak Out; We Depend On It" in OPINION of the March 2000 issue clashes with his leadership in destroying Congress's Office of Technology Assessment, in which scientists and technologists worked effectively to inform Congress of technical opportunities and limits in studies assigned to the Office. I served on several advisory committees to the late OTA, with others of contrasting views. Mr. Gingrich should lead an initiative to recreate OTA.
Richard L. Garwin
Thomas J. Watson Research Center
I disagree in a few minor ways with the list of top ten physicists. Here is my own list (which includes 11 names):
1. Newton
2. Einstein
3. Maxwell
4. Galileo
5-7 (tie). Heisenberg, Schr"dinger, Dirac
8. Faraday
9. Rutherford
10-11 (tie) Bohr, Fermi
I put Newton ahead of Einstein because he not only was a great theorist but he invented the mathematics (calculus) that he needed. Furthermore, he was also a good experimentalist, especially in optics. Galileo's position is improved because Newton built on Galileo's initial achievements.
I cannot decide who was the best among Heisenberg, Schrodinger, and Dirac. Not only did Schrodinger formulate wave mechanics but showed it was equivalent to Heisenberg's matrix mechanics. He also first wrote down the relativistic wave equation known as the Klein-Gordon equation. Dirac's relativistic theory of the electron not only explained the electron's spin and (to a very good approximation) its magnetic moment, but it predicted the existence of antiparticles.
Faraday was surely the best experimental physicist of the 19th century if not of all time. Bohr was a great physicist, but his work had a very provisional character, being the best theory of the H atom for only a few years, so I downgraded him.
I had to include Fermi because he was a great experimentalist as well as a great theorist-the only renaissance physicist of the 20th century. I was sorry to omit Feynman, but I also omitted a large number of other great physicists.
Don Lichtenberg
Indiana University
©1995 - 2023, AMERICAN PHYSICAL SOCIETY
APS encourages the redistribution of the materials included in this newspaper provided that attribution to the source is noted and the materials are not truncated or changed.