Physics

Exploring the Art and Science of Stopping Time: The Life and Work of Harold E. Edgerton

This is the first time that something not printed on paper has been chosen for Hal's Picks, and it probably will not happen often in the future. This particular subject is, however, better treated in digital format than in a book (although several good books on Edgerton and his work are also available).

Sport: Extreme Stargazing

For anyone who has tried unsuccessfully (like me) to find familiar stars in well-known constellations through a telescope, the competition that David Freedman describes sounds impossible. The "sport" is to see how many of the 110 celestial objects in the Messier catalog you can locate and identify during a single night of observation.

Medicine on Mars

I'm not a big fan of science fiction. I find "real" science to be generally more interesting; the fictionalized kind usually requires me to pretend that the universe is far different than what I believe to be the case. In fiction, travel between planets (or even solar systems) is accomplished quite easily, by suspension of the speed limit imposed by relativity.

The Search for Superstrings, Symmetry, and the Theory of Everything

For most of us chemists, our knowledge of the universe is pretty good from the atomic level upward, but when students ask us (as they sometimes do) about what it is that holds the nucleus together, or what a "string" is, or about quarks, leptons, and any of the other particles that are not electrons, protons, or neutrons, we begin to mumble.

Why Shake Your Fever Thermometer? - and More

If you have ever wondered (as I have) how a fever thermometer actually works (but have never felt good enough while you were wondering to do any investigation) then you should look at this article in "How Things Work", a feature of The Physics Teacher edited by H. Richard Crane of the Physics Department of University of Michigan.

Observation of Interference Between Two Bose Condensates

The very first of "Hal's Picks", back in 1995, was the announcement of the first experimental observation of a Bose-Einstein condensate. This can be considered as a new phase of matter, in which atoms in a cold cluster lose their separate identities, because their deBroglie wavelengths exceed the dimension of the group in which they find themselves.