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Russian military leaders have expressed concern about US plans
for a national missile defense system. Will defense technology be
limited by possibilities for a strategic imbalance? Is this just SDI
all over again?
(7631 previous messages)
- 07:26am Jul 31, 2001 EST (#7632
Organizing facts is hard work.
Sometimes requirements of organization are different for
different needs and circumstances.
To fit different minds, in real circumstances.
Sometimes, organizations of material, and human organizations,
too, work well for some purposes, but badly for others.
You need both long and short forms, and forms differently
organized, for different jobs.
For example, nobody thinks depositions or jury transcripts can be
short. And for crucial decision making, those formats are
indispensible -- but unworkably cumbersome for other purposes --
where summaries are needed. Summaries that people can trust, feel
comfortable with, and understand.
On missile defense, some of the central issues might be easy
"from the right distance" but are not easy for the people involved,
because so much hangs on them, and because re-evaluating some facts
might require reevaluation of much else.
Related issues of military balance (and it is these issues
that most concern almarst MD5539 rshowalter
6/20/01 12:24pm ) make things hard, as well.
- 07:27am Jul 31, 2001 EST (#7633
The specific technical issues of missile defense that are
crucial are sometimes pretty simple, but they connect to sets
of problems involving huge numbers of people, many resources, great
risks, over a long time - -
Concerns about the “military-industrial complex”
were set out in the FAREWELL ADDRESS of President Dwight D.
Eisenhower …… January 17, 1961. http://www.geocities.com/~newgeneration/ikefw.htm
and the connections of the simple facts to the larger
circumstances make everything harder than it might otherwise be.
- 07:31am Jul 31, 2001 EST (#7634
For example, it is a fact that it is easy to make reflective
coatings that take absorbtion of light from a lasar beam down by a
factor of 1000 - - and easy to put these coatings on missiles and
warhead - with something as simple as contact paper. The key fact is
old, and the coating technologies involved are well known to the
engineers working on lasar weaponry. They use multilayered tuned
reflectie coatings. http://www.phy.davidson.edu/jimn/Java/Coatings.htm
The simple fact above is fatal to the lasar weaponry programs that
have been proposed.
For another example, it is a fact that the resolution of Hubble
Space Telescope, one of the highest resolution optical systems in
existence, is only as good as it is. The resolution Hubble shows,
impressive as it is, is grossly less than the proposals for lasar
based anti-missile weapons would need. One can see that, and get a
sense of it, by looking at some beautiful pictures from Space
dec97-hubble butterfly http://www.astrophys.org/high_2001.html
These are beautiful Hubble pictures --- go down, and look at the
detailed ones, and get a physical sense of what astronomers mean
when they say that an angle can be "resolved." . . . . These
pictures are awesome - and one example, among many, of work the
Americans can be proud of.
But if you look at the blurs, which are images of stars that are
essentially point sources, you get a sense of the limits of optical
perfection (even when power levels are low.) Eric Chaison
illustrates those limits in The Hubble Wars Space telescope
could just resolve the difference between a car with one headlight,
or two, from a distance of 2000 miles. (Chaison's example is for a
car in emply space - the smearing of the atmosphere would make the
seeing much worse.) Enough resolution to resolve between one
headlight and two for "a car in space at 2000 miles) is wonderful
resolution. But not nearly good enough for some of the "death
ray" schemes people seem to have been imagining, and drawing
pictures about, and writing about without considering the
The stars are so far away, that they are
essentially point sources -- with angles like 10e-12 radians -- --
the imperfection of the optics smears them into "blobs" with a
resolution of 5 x 10e-7 radians, or "worse." And that just isn't
good enough for a "death ray" in space. The death ray idea makes
sense (if you don't remember about reflective coatings) if you
forget the resolution numbers. But the numbers rule that dream
gisterme argued that, for "point sources" that are intense
enough, the geometrical issues don't hold, and don't limit what can
be destroyed. MD6695 gisterme
But that's wrong.
Now, the fact that reflective coatings are easy to make is a
simple fact. The fact that resolution limits how well a "death ray"
can be aimed, and the damage it can do, is a simple fact.
But these are not simple facts to people involved who are deeply
committed to programs that cannot work.
* * * * *
We're facing problems similar to paradigm conflict here.
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