Carleton College Physics and Astronomy

Weekly Bulletin March 29 - April 3

Friday, March 29 12:00 CTR

PHYSICS / ASTRONOMY TABLE: Meet in Olin 309 at 11:50 a.m. for the walk to the CTR or join us and Physics 123 speaker, Dr. Hevly, there at noon.

Friday, March 29 1:10 to 2:10 Olin 141

PHYSICS 123 TALK: "Rediscovering the Physics of Glaciers." by Dr. Bruce Hevly, (`82) of the Department of History at the University of Washington. All are welcome. Refreshments available. An article on this topic is on reserve in the Science Library.

Monday, April 1 3:10 Olin 109

Comps talk by Keith Barnes: "Fission Reactors"

Wednesday, April 3 3:10 Olin 109

Comps talk Nathan Sandbo: ""Physical Models of Mental Phenomena"

1. Physics 123, What Physicists Do: Guest Speakers

Rediscovering the Physics of Glaciers -- March 29. Dr. Bruce Hevly (`82), Department of History, University of Washington. The author discovered this topic as a Carleton physics major, and it became the subject of his comprehensive exercise in 1981. As a historian of science, he rediscovered the project and undertook work on the origins of glacier physics in nineteenth-century Britain. This talk will reflect upon how glaciers move, what they meant to the emerging subject of "physics" early in the nineteenth century, and what they mean to the author's project of integrating history and physics in his own education.

How Old Is The Universe? -- April 5. Dr. Donald Goldsmith, Interstellar Media. For decades, astronomers have concluded that the universe began--at least in its present form--some 15 to 20 billion years ago, in a moment of titanic fury, called the "big bang," that filled all of space with new matter and energy. This age estimate squared reasonably well with the ages derived for the oldest stars, approximately equal to 16 billion years. But new observations made with the Hubble Space Telescope, and with the greatest Earthbound instruments, now imply that the universe seems no older than 13 billion years, and that a mere 8 billion years may have elapsed since the big bang. Since the universe can hardly be younger than its oldest stars, the new results imply either that astronomers' determinations of stellar ages must be wrong, or that their theories of the universe must be wrong, or that they have missed something else in their attempts to understand the cosmos. Dr. Goldsmith will describe these puzzles, in addition to discussing what it means and takes to work as a science popularizer. He has written or edited 15 astronomy and physics books, written scripts for several television documentaries, and won numerous awards for his educational efforts in astronomy.

Three-Stage Lattice Relaxation of Ge on Si(111) -- April 19. Dr. Silva Leonard Theiss (`87), AT&T Bell Laboratories Understanding strain relaxation during the growth of one crystal on another is important to the creation of semiconductor devices. The scanning tunneling microscope (STM) allows us to make measurements of strain on an extremely short length scale. STM measurements of strain relaxation in Ge islands growing on Si(111) reveal a very surprising interplay between plastic and elastic relaxation mechanisms.

Engineering: Moving Protons, Not Trains -- April 26. Elaine McKluskey (`77), Facilities Engineering Group, Fermi National Laboratory. Elaine went from Carleton to Washington University where she earned a B.S. in Civil Engineering under the 3-2 Program in 1978. For six years she worked as a structural engineer for consulting firms in Minneapolis and Chicago. Subsequently, she worked as a consultant for private industry and government agencies, including Fermilab. Recently she became lead structural engineer for the Facilities Engineering group at Fermilab, working to build and maintain facilities for high-energy physics research. Her talk will focus on her experiences at Fermilab.

Nuclear Magnetic Resonance Imaging -- May 3. Dr. Armando Manduca, Department of Physiology and Biophysics, Mayo Clinic. Dr. Armando Manduca is an astrophysicist who once worked with the Hubble Space Telescope and is currently involved with a variety of exciting research projects in the field of medical imaging. Using his astronomical image processing and analysis skills, Dr. Manduca has brought his talents to focus on several research problems in diagnostic imaging of the human body. He will present the basic physical principles involved in nuclear magnetic resonance imaging and discuss his current work on imaging the elasticity of tissues.

Last modified and validated on: Mon April 22 16:34:01 CDT 1996