No more giggling at the gigawatts in antimatter
THE Starship Enterprise would boldly go nowhere without its antimatter fuel. But in the ``real world,'' this most powerful of all possible energy sources has remained a plaything for experimenters and a gimmick for sci-fi authors. Perhaps it's time to take it more seriously. What farsighted engineer can ignore a substance that, upon contact with normal matter, induces the total transformation of both forms of matter into pure energy?
That's why the United States Air Force has been sponsoring studies of antimatter uses as part of a $5 million-a-year high-energy materials program. Col. Ross Nunn, who commands the USAF Astronautics Laboratory, says ``the `giggle factor' is over'' in considering antimatter applications, according to the industry journal Aviation Week.
Engineers like antimatter, in theory, because, with it, they can store more energy in a smaller mass and volume than with any other substance. If it could be used to power the US space shuttle system, engineers could pack the energy equivalent of the liquid and solid propellent into a mass the size of a sugar cube.
Antimatter is just like ordinary matter, except that certain properties, such as electric charge, are reversed. British physicist Paul Dirac introduced the concept six decades ago when he brought the then young theory of quantum physics into line with Einstein's theory of special relativity. Since then, physicists have found it in cosmic rays and created it in particle accelerators. There is now no doubt that they could produce whole atoms of antimatter - for example, antihydrogen. The challenge is to learn how to make it, store it indefinitely, and control it in safe and economically practical ways.
Since antimatter can't touch container walls, physicists at accelerator laboratories control it with magnetic forces inside large evacuated rings. Practical applications need more compact, efficient methods. Concepts now under investigation include using laser light as well as electromagnetic fields to help manipulate antimatter - perhaps in the form of antihydrogen ice - within vacuum containers.
The European Laboratory for Particle Physics (CERN), in reviewing such prospects last year, observed that it still ``would be pure science fiction to try to stock even a millionth of a gram [of antihydrogen] in volumes that were both feasible and transportable.''
Robert L. Forward, who recently retired as senior scientist at Hughes Research Laboratories, and science writer Joel Davis take a more visionary approach in their new book, ``Mirror Matter'' (New York: John Wiley & Sons), saying: ``No physical laws will be violated. Mirror matter, in some form, will someday be made and stored in enough quantity to produce megawatts and gigawatts of prime power and propulsion needed for space travel.''
One may be skeptical about the timing. But it's no longer a prospect to giggle at.
A Tuesday column. Robert C. Cowen is the Monitor's natural science editor.