APS News

February 2013 (Volume 22, Number 2)

Letters to the Editor

Criticism of Inquiry-based Learning Strikes Home

David Klahr in his Back Page “Inquiry Science rocks: Or does it?” in the December APS News clearly shows that the inquiry-based emperor, despite his legions of loyal followers, has no clothes. The most telling criticism in Klahr’s essay is the lack of any clear “dose-response” correlation between positive results of particular educational materials and their degree of being inquiry-based. What a delightful irony that he faults much of physics education research for its lack of methodological rigor and clear definitions–properties which many physics education researchers presume to be hallmarks of their field, perhaps by virtue of their being physicists, unlike Klahr.

Bob Ehrlich
Fairfax, VA

G. N. Lewis Column Stirs Memories

I enjoyed the “This Month in Physics History” column in the December APS News on G. N. Lewis, which reminded me of a couple of anecdotes:

At the Centennial meeting of APS in 1999, H. Richard Crane (my academic grandfather) gave a talk about his days working with Lauritsen at Caltech in the 1930s on accelerated deuterons, made possible by a gift of D2O by G. N. Lewis. Someone in the lab mentioned to a journalist about the connection of D2O to nuclear physics, and the subsequent newspaper story was like something you’d see in the National Enquirer today. Lewis was furious and cut off their supply of D2O, and Crane had to set up apparatus to make his own.

I visited Rob Varney and Leon Fisher (both of whom died recently) a few years ago in California. They had been grad students at Berkeley in the late 1930s to early 1940s and used to play bridge with G. N. Lewis. Varney and Fisher said that after Berkeley became recognized for nuclear physics, Lewis was determined to do nuclear work on his own. He gave a seminar in physics telling of being able to focus neutrons using a paraffin lens in his lab. They said that both Lawrence and Oppenheimer mercilessly ridiculed Lewis's results at the seminar, insisting that the neutrons he detected must have been bouncing off furniture and walls. Varney and Fisher added that when Lewis repeated the experiments out-of-doors he found no such focusing of neutrons, and that the humiliation seemed to have taken the steam out of him. They felt that he didn’t do much after that, but of course by that time he was getting on in years [Lewis was born in 1875–ed.]. I’ve always wondered if this story is at all widely known.

Thomas M. Miller
Lexington, MA

Arms Policy Demands Broader Perspective

The debate on the Benefits and Risks of Laser Isotope Separation between Mark Raizen and Francis Slakey (January APS News Back Page) raises interesting points that, ultimately, are relevant to the development of any defense (but therefore also war-enabling) technology that some possess but do not wish others to have. Raizen and Slakey could have been talking about bows, arrows, guns and gunpowder that all have access to now. Or, they could have been talking about nuclear, biological and chemical weapons that all do not have today–but which are likely to become widespread,  if we do not change our ways.

Unfortunately the debate does not address the root cause of many of our difficulties: We do not recognize that our conflicts can only really be resolved by negotiation rather than by slaughtering one another. No matter how hard we try to prevent “others” from acquiring the deadly weapons that we so dearly guard because we are “civilized” while they are not, these others will eventually also acquire them. The reason is simple. All technology is based on science and, if we have learned anything from the latter, it is that what can be done in one place at one time can be repeated in any other place at any other time. The laws of physics are invariant.

If we have nuclear technology today others will acquire it tomorrow. If we fly drones over other countries today they will have the capacity to do the same over ours –one day.

We may try to continuously stay a step ahead and hope that our defenses will be able to shield us while they attempt to catch up. But that is a dangerous game. A perfect shield against any weapon is an impossibility.

More physicists, engineers and other scientists ought to try and have a broader perspective and recognize the plight of people all around the world. In that way perhaps we could persuade our politicians to also look at the world without the blinders they seem to have on.

Then they may not be as trigger-happy.

I cannot help but make one final comment, though. Admirably, Slakey exhibits that broad perspective and refers to the poverty of many in the world. I do take issue, however, with the “tribeswoman” appellation applied to that woman trekking miles to fetch water. One of the problems we have here in the “West” is that we often look at those whose cultures we may not understand well as being somewhat inferior.

Amin Dharamsi
Norfolk, VA

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.

Editor: Alan Chodos
Staff Science Writer: Michael Lucibella