Letters

AP Physics: Irrelevant, Boring, and Too Difficult

In his "Viewpoint" article "Scientific Literacy and Education Reform," (Aug/Sep 2005), Warren Huelsnitz states: "The scientific literacy of the general public is at an unacceptably low level and many people believe that physics is irrelevant, boring, and too difficult. ...It would be nice if the general public understood the scientific process and was able to use logic and reasoning. …We need a captive and receptive audience, one that is still impressionable, and where we have an opportunity to reach all of society. We can find this in our nation's elementary and secondary education system. We need to change the mentality of how math and physics are taught…. We need to make science interesting."

I couldn't agree more.
To achieve physics literacy as a nation we must change our approach to high school physics. Many schools offer an Advanced Placement first course for scientists that is highly mathematical and precisely of the "irrelevant, boring, and too difficult" variety of which Huelsnitz speaks. Very few non-science students will take such a course, and very few science students will learn "the scientific process and …logic and reasoning" from such a course. Many schools offer a less technical first course aimed at non-scientists, but many science students will skip this course in favor of an AP (or other math-based) course, and most such courses are patterned after standard math-based introductory courses, offer no social or cultural relevance, offer very little scientific process or critical thinking, and are boring.

Huelsnitz's admirable criteria could be met by a first physics course required for all students, future scientists and non-scientists alike, that is conceptual, process-oriented, socially relevant, and scientifically broad. More precisely, "conceptual" means using little or no algebra while still being "numerate" (metric system, powers of ten, graphs, probabilities, proportionalities, etc.). "Process-oriented" means focusing explicitly on the scientific process, and including a critique of pseudoscience and other loose thinking. "Socially relevant" means including such physics-related social issues as global warming, nuclear weapons, and the energy future. And "scientifically broad" means emphasizing so-called "modern" (an ironic term for physics since 1900!) physics and including contemporary topics such as the standard model and the current golden age of cosmology. The "physics first" movement (physics in 9th grade, then chemistry, then biology) could accomplish this, but a required course in 10^th, 11^th, or 12^th, grade could also do the job.
Art Hobson
Fayetteville, AR

Infrared Laser First Described in Dicke Patent

I would like to offer a brief personal note on “This Month in Physics History” from the August/September 2005 APS News, which describes the origin of the mirror-feedback ideas relevant to the laser.

As a young professor at Princeton in the mid 60's, I had the good fortune to have an office next to that of R.H. Dicke. I would often thus hear his minor musings on science and technology (major ones he saved for others). One day he came in waving two printed items, with a broad smile on his face. The first was a newspaper article describing the Townes-Gould lawsuit over who was responsible for the mirror-feedback idea in the Townes-Schawlow laser patent, "Masers and Maser Communication Systems." They had applied for the patent on July 30, 1958 with the relevant physics described in a paper sent to the Physical Review August 26, 1958. The other was US patent 2851652, applied for by Dicke on May 21, 1956 and issued on September 9, 1958. Dicke's patent, "Molecular Amplification and Generation Systems and Methods," describes, among other things, how to build an infrared laser, using a cavity with parallel mirrors at the ends, with many small holes in the reflective surface to couple the energy to the exterior.

This patent application predates all reliably dated references I know to discussions between Townes, Schawlow, and Gould about the kind of feedback cavity that would be appropriate for infrared wavelengths. Bob mused, “I wonder what I should do with this? Maybe I should send a copy of it to the judge.” I believe he did so. However, the lawsuit was not about the validity of the Townes-Schawlow patent, but rather about the disputed origin of one of the seminal ideas in the patent, assuming it to be valid.

Bob never chose to pursue the legal issue–in the mid 60's he was done with his phase of invention and patenting, and a lawsuit would have distracted him from the physics he was so enthusiastically pursuing. By taking only the patent route, he failed to influence the subsequent development of laser mirror feedback ideas alluded to in the APS News article.
John Hopfield
Princeton, NJ