APS News


Physicists Must Recognize Limits to Growth

I was troubled by some aspects of the letter by Prager and Hazeltine responding to Congressman Dana Rohrabacher. (APS NEWS, August/September 1995) The subject was research on nuclear fusion, which Rohrabacher had questioned, and which P&H defended.

In their second paragraph, Prager and Hazeltine state that "the fusion power generated in experiments... has grown by a factor of 10 million during the past 20 years...." I would have a better understanding of what they wrote if the word "power" was replaced by "energy." But I would still be troubled by the meaning of "break even."

If the output of a fusion machine consists of pulses of thermal energy of a duration of one second, with a cycle time of one pulse every thousand seconds, then the output thermal energy in one cycle is the integral of the output power over the one-second duration of the pulse. But does this thermal energy output represent the approximate efficiency with which thermal energy may be converted to electrical energy? How do you calculate the energy output? And does the energy output include some estimate of the total energy required to develop, manufacture, and test the apparatus so that the total output energy can be compared with the total energy input to get some idea of the "net energy"?

I was also troubled by the assertion that fusion is "a source of virtually unlimited energy whose intrinsic advantages regarding... global warming... are unmatched." Fusion itself does not produce CO2, but the energy it produces contributes directly to warming of the areas where the energy is generated and used, and ultimately to global warming.

I firmly believe that research on fusion should be continued. In a new and extremely complicated technology, it is a very long way from the "break even" point to the reliable delivery of global supplies of electrical energy.

It is most important that we take steps now to halt the growth of demand for electrical energy in the U.S. We must recognize that there are limits to growth.

Albert Bartlett
Boulder, Colorado

Prager and Hazeltine Response

We clarify two technical points in response to Albert Bartlett's letter. First, we employed the common definition of breakeven, in which the fusion power produced (power carried by fusion reaction products) is equal to the power applied to heat the plasma. Often referred to as "scientific breakeven," it is obviously short of the goal of a commercial power plant. The point we made in our letter was that having achieved breakeven plasma conditions, fusion scientists are shifting their focus to other physics challenges of fusion. The second point concerns the contribution of waste heat to global warming. The main point is that greenhouse gases trap solar energy. Since the solar heat load on earth far exceeds the heat produced in power plants, greenhouse gases pose a much more imminent environmental threat than waste heat. Fusion does not produce greenhouse gases.

Don't Make Science a Partisan Issue

Jeff Bingaman, spare us the "Vote for Me" rhetoric. Please don't make science a partisan issue. It's not the "new Republican majority in Congress," but the majority of the population that does not support basic research, and has not fully grasped the implications of a strong science and technology program. For better or worse, this new Congress of populists are doing exactly what the majority of Americans want. Politicians are simply doing what every post-doc does in every university department: scrambling to ensure their own survival.

The simple fact is that Americans have to be shown the value of basic science, and that includes Congress. By all means, lobby Congress with faxes, phone calls, and petitions. It worked for the health food industry when "the People" said they didn't want federal regulations of health items. Organizationally sponsored commercials, contests, scholarships and the ilk address a small portion of the problem.

There is something we can do while waiting for Congress to figure this out for us. We can begin in the schools, in our children's early education _ not a government-sponsored, federally mandated program, but taxpayers rising up and acting en masse to dedicate not money, not new books, not new computers, but time. If you are any kind of scientist or engineer, volunteer your time at the local school. Set up science days, demonstrate an interesting project, help out with the local science fair. And of course there is always the elementary school teacher with no background in science who desperately needs to ask you a few questions. Volunteer to speak on career day. If someone you know makes an irrational, patently ridiculous statement, set them straight (preferably with good humor; no derision allowed). At the dinner table, purposefully introduce some new scientific innovation you read about.

Most importantly, descend on the local schools in your district and force them to remove the fluff from the curriculum. Kids cannot think about anything if they have no facts to think with! Donate your favorite textbooks, science fiction, medical mystery, or biography or physics tome to a local school library. We, as concerned citizens, must take matters into our own hands.

Crystal Barker
Tucson, Arizona

Recent Experiments Make Strong Case for Dowsing

We read with interest the article on alternative science (APS NEWS, June 1995) reporting on the comments of James Randi, Hal Lewis, and Robert Park, and the subsequent exchange between A.R. Liboff, William C. Meecham, and Park in the August/September issue. Randi, Lewis and Park claim to have no difficulty in determining which claims of new phenomena are real and which are bogus, and even offer guidelines to help anybody else make such decisions. Would that scientific research were so simple!

In the later exchange, Liboff and Park focus on dowsing. From a theoretical point of view, a physicist is sorely tempted to assert that dowsing is impossible, since there is no evidence that sources of water produce perturbations in the electric, magnetic, or gravitational fields with parameters that would lead one to expect that the perturbations would be detectable by living organisms. Concerning experimental evidence, Park makes the assertion that, "With a series of skillfully designed double-blind tests, Randi demonstrated that dowsing has nothing to do with anything, except perhaps self-deception." We respectfully suggest that this assertion errs on the wrong side of caution.

In two recent articles [J. Sci. Exp., Vol. 9, 1-44 and 159-190, 1995], Hans-Dieter Betz, a professor of physics at the University of Munich, reports on an extensive study of dowsing that involved both field work and laboratory investigations. If taken at face value, this report makes a strong case for the reality of the phenomenon. If one asks whether such evidence proves conclusively that dowsing is a real phenomenon, we expect that most scientists would answer in the negative. On the other hand, if one asks whether this and related evidence for such a phenomenon is ignorable, there is likely to be a difference of opinion among those who have reviewed the evidence.

Since water supplies are always important _ sometimes critically important _ for a society, it would be irresponsible for scientists to discount a potentially valuable tool for finding new water supplies by basing their response on theoretical arguments, on guidelines such as those proposed by Randi, Lewis and Park, or on one negative result, for which no journal citation is provided.

Lawrence W. Frederick, University of Virginia
Peter A. Sturrock, Stanford University
Robert M. Wood, Newport Beach, CA

APS Should Stay Out of Politics

The APS should not be taking political positions nor fostering lobbying efforts. I have never been polled, as an APS member, on my position on NIST. If you had asked, this is what I would have said and have been saying both to NIST personnel and others for several years:

I believe that a much smaller NIST, renamed National Bureau of Standards and devoted to the basic "weights and measures" mission, with an annual budget of $100 -$150 million, would serve the U.S. much better. It could even move back to its original building on the Naval Observatory Grounds, if it is available.

The present bloated establishment, with its oversize campus and staff, could be privatized and become, overnight, one of the great technical universities of the world. Then good things would occur, depending on the needs of the free market.

Jonathan Black
King of Prussia, Pennsylvania

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Editor: Barrett H. Ripin