October 2004


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Carmelo Ruiz <[log in to unmask]>
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Science for the People Discussion List <[log in to unmask]>
Sun, 10 Oct 2004 19:29:22 -0700
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--- Global Network <[log in to unmask]> wrote:

> Date: Sun, 10 Oct 2004 12:11:02 -0400
> Air Force pursuing antimatter weapons
> Program was touted publicly, then came official gag
> order
> - Keay Davidson, Chronicle Science Writer
> Monday, October 4, 2004
> The U.S. Air Force is quietly spending millions of
> dollars investigating ways to use a radical power
> source -- antimatter, the eerie "mirror" of ordinary
> matter -- in future weapons.
> The most powerful potential energy source presently
> thought to be available to humanity, antimatter is a
> term normally heard in science-fiction films and TV
> shows, whose heroes fly "antimatter-powered
> spaceships" and do battle with "antimatter guns."
> But antimatter itself isn't fiction; it actually
> exists and has been intensively studied by
> physicists since the 1930s. In a sense, matter and
> antimatter are the yin and yang of reality: Every
> type of subatomic particle has its antimatter
> counterpart. But when matter and antimatter collide,
> they annihilate each other in an immense burst of
> energy.
> During the Cold War, the Air Force funded numerous
> scientific studies of the basic physics of
> antimatter. With the knowledge gained, some Air
> Force insiders are beginning to think seriously
> about potential military uses -- for example,
> antimatter bombs small enough to hold in one's hand,
> and antimatter engines for 24/7 surveillance
> aircraft.
> More cataclysmic possible uses include a new
> generation of super weapons -- either pure
> antimatter bombs or antimatter-triggered nuclear
> weapons; the former wouldn't emit radioactive
> fallout. Another possibility is antimatter- powered
> "electromagnetic pulse" weapons that could fry an
> enemy's electric power grid and communications
> networks, leaving him literally in the dark and
> unable to operate his society and armed forces.
> Following an initial inquiry from The Chronicle this
> summer, the Air Force forbade its employees from
> publicly discussing the antimatter research program.
> Still, details on the program appear in numerous Air
> Force documents distributed over the Internet prior
> to the ban.
> These include an outline of a March 2004 speech by
> an Air Force official who, in effect, spilled the
> beans about the Air Force's high hopes for
> antimatter weapons. On March 24, Kenneth Edwards,
> director of the "revolutionary munitions" team at
> the Munitions Directorate at Eglin Air Force Base in
> Florida was keynote speaker at the NASA Institute
> for Advanced Concepts (NIAC) conference in
> Arlington, Va.
> In that talk, Edwards discussed the potential uses
> of a type of antimatter called positrons.
> Physicists have known about positrons or
> "antielectrons" since the early 1930s, when Caltech
> scientist Carl Anderson discovered a positron flying
> through a detector in his laboratory. That
> discovery, and the later discovery of "antiprotons"
> by Berkeley scientists in the 1950s, upheld a 1920s
> theory of antimatter proposed by physicist Paul
> Dirac.
> In 1929, Dirac suggested that the building blocks of
> atoms -- electrons (negatively charged particles)
> and protons (positively charged particles) -- have
> antimatter counterparts: antielectrons and
> antiprotons. One fundamental difference between
> matter and antimatter is that their subatomic
> building blocks carry opposite electric charges.
> Thus, while an ordinary electron is negatively
> charged, an antielectron is positively charged
> (hence the term positrons, which means "positive
> electrons"); and while an ordinary proton is
> positively charged, an antiproton is negative.
> The real excitement, though, is this: If electrons
> or protons collide with their antimatter
> counterparts, they annihilate each other. In so
> doing, they unleash more energy than any other known
> energy source, even thermonuclear bombs.
> The energy from colliding positrons and
> antielectrons "is 10 billion times ... that of high
> explosive," Edwards explained in his March speech.
> Moreover, 1 gram of antimatter, about 1/25th of an
> ounce, would equal "23 space shuttle fuel tanks of
> energy." Thus "positron energy conversion," as he
> called it, would be a "revolutionary energy source"
> of interest to those who wage war.
> It almost defies belief, the amount of explosive
> force available in a speck of antimatter -- even a
> speck that is too small to see. For example: One
> millionth of a gram of positrons contain as much
> energy as 37.8 kilograms (83 pounds) of TNT,
> according to Edwards' March speech. A simple
> calculation, then, shows that about 50-millionths of
> a gram could generate a blast equal to the explosion
> (roughly 4,000 pounds of TNT, according to the FBI)
> at the Alfred P. Murrah Federal Building in Oklahoma
> City in 1995.
> Unlike regular nuclear bombs, positron bombs
> wouldn't eject plumes of radioactive debris. When
> large numbers of positrons and antielectrons
> collide, the primary product is an invisible but
> extremely dangerous burst of gamma radiation. Thus,
> in principle, a positron bomb could be a step toward
> one of the military's dreams from the early Cold
> War: a so-called "clean" superbomb that could kill
> large numbers of soldiers without ejecting
> radioactive contaminants over the countryside.
> A copy of Edwards' speech onNIAC's Web site
> emphasizes this advantage of positron weapons in
> bright red letters: "No Nuclear Residue."
> But talk of "clean" superbombs worries critics. "
> 'Clean' nuclear weapons are more dangerous than
> dirty ones because they are more likely to be used,"
> said an e-mail from science historian George Dyson
> of the Institute for Advanced Study in Princeton,
> N.J., author of "Project Orion," a 2002 study on a
> Cold War-era attempt to design a nuclear spaceship.
> Still, Dyson adds, antimatter weapons are "a long,
> long way off."
> Why so far off? One reason is that at present,
> there's no fast way to mass produce large amounts of
> antimatter from particle accelerators. With present
> techniques, the price tag for 100-billionths of a
> gram of antimatter would be $6 billion, according to
> an estimate by scientists at NASA's Marshall Space
> Flight Center and elsewhere, who hope to launch
> antimatter-fueled spaceships.
> Another problem is the terribly unruly behavior of
> positrons whenever physicists try to corral them
> into a special container. Inside these containers,
> known as Penning traps, magnetic fields prevent the
> antiparticles from contacting the material wall of
> the container -- lest they annihilate on contact.
> Unfortunately, because like-charged particles repel
> each other, the positrons push each other apart and
> quickly squirt out of the trap.
> If positrons can't be stored for long periods,
> they're as useless to the military as an armored
> personnel carrier without a gas tank. So Edwards is
> funding investigations of ways to make positrons
> last longer in storage.
> Edwards' point man in that effort is Gerald Smith,
> former chairman of physics and Antimatter Project
> leader at Pennsylvania State University. Smith now
> operates a small firm, Positronics Research LLC, in
> Santa Fe, N.M. So far, the Air Force has given Smith
> and his colleagues $3.7 million for positron
> research, Smith told The Chronicle in August.
> Smith is looking to store positrons in a
> quasi-stable form called positronium. A positronium
> "atom" (as physicists dub it) consists of an
> electron and antielectron, orbiting each other.
> Normally these two particles would quickly collide
> and self-annihilate within a fraction of a second --
> but by manipulating electrical and magnetic fields
> in their vicinity, Smith hopes to make positronium
> atoms last much longer.
> Smith's storage effort is the "world's first attempt
> to store large quantities of positronium atoms in a
> laboratory experiment," Edwards noted in his March
> speech. "If successful, this approach will open the
> door to storing militarily significant quantities of
> positronium atoms."
> Officials at Eglin Air Force Base initially agreed
> enthusiastically to try to arrange an interview with
> Edwards. "We're all very excited about this
> technology," spokesman Rex Swenson at Eglin's
> Munitions Directorate told The Chronicle in late
> July. But Swenson backed out in August after he was
> overruled by higher officials in the Air Force and
> Pentagon.
> Reached by phone in late September, Edwards
> repeatedly declined to be interviewed. His superiors
> gave him "strict instructions not to give any
> interviews personally. I'm sorry about that -- this
> (antimatter) project is sort of my grandchild. ...
> "(But) I agree with them (that) we're just not at
> the point where we need to be doing any public
> interviews."
> Air Force spokesman Douglas Karas at the Pentagon
> also declined to comment last week.
> In the meantime, the Air Force has been
> investigating the possibility of making use of a
> powerful positron-generating accelerator under
> development at Washington State University in
> Pullman, Wash. One goal: to see if positrons
> generated by the accelerator can be stored for long
> periods inside a new type of "antimatter trap"
> proposed by scientists, including Washington State
> physicist Kelvin Lynn, head of the school's Center
> for Materials Research.
> A new generation of military explosives is worth
> developing, and antimatter might fill the bill, Lynn
> told The Chronicle: "If we spend another $10 billion
> (using ordinary chemical techniques), we're going to
> get better high explosives, but the gains are
> incremental because we're getting near the
> theoretical limits of chemical energy."
> Besides, Lynn is enthusiastic about antimatter
> because he believes it could propel futuristic space
> rockets.
> "I think," he said, "we need to get off this planet,
> because I'm afraid we're going to destroy it."
> E-mail Keay Davidson at [log in to unmask]
> Global Network Against Weapons & Nuclear Power in
> Space
> PO Box 652
> Brunswick, ME 04011
> (207) 729-0517
> (207) 319-2017 (Cell phone)
> [log in to unmask]

Carmelo Ruiz-Marrero
Director, Proyecto de Bioseguridad
Research Associate, Institute for Social Ecology
Fellow, Environmental Leadership Program
Senior Fellow, Society of Environmental Journalists

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