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Missile Defense

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?

rshowalter - 09:14pm Jul 16, 2001 EST (#7105 of 7109)
Robert Showalter showalte@macc.wisc.edu

"The implications of these problems are that:

"There are problems which we simply can't deal with yet, even with the aid of computers.

"It is often necessary to screen out all but the most relevant laws to a given scenario. At this point, the simulation becomes an approximation and can no longer be expected to provide perfectly accurate results.

"This idea will be demonstrated later in the actual program and therefore need not be discussed further here.

Comment: Compared to the missile defense problems, the example is an easy one - - comparatively -- but, even so, still impossibly hard, for the accuracy MD would take for multiple warheads, and realistic decoys.

It is often most practical to break continuums into quantized quantities. For example, in this program, a time variable is "stepped" through time by some interval dt. Unless dt is infinitely small (this would require symbolic evaluation of calculus functions), the simulation becomes even more of an approximation.

Translation: sometimes, even with computers, you actually have to solve the differential equations involved analytically, or you are lost.

"Normally, smaller dts provide more accurate results than larger ones. However, if a block of time is broken into smaller intervals, it should be apparent that there will be more of these intervals (thus requiring more computations and therefore more time for the simulation to run). A balance must be found between acceptable error tolerances for a given simulation and acceptable completion time. "

Comment: The mathematical "showstoppers" in missile defense are dense and for any of the defensive problems that the system is really supposed to do -- provably impossible.

Anybody with a face and a name willing to stnd up and contest this? Anybody want to show that these things can be done, on streaming video -- where things can be checked?

Anybody want to contest the point that these issues have been lied about at many stages in the funding and execution of the missile defense efforts so far?

rshowalter - 09:24pm Jul 16, 2001 EST (#7106 of 7109)
Robert Showalter showalte@macc.wisc.edu

Before I have a beer, and knock off for tonight, I'd like to make some nonquantitative but heartfelt points.

MD4043 rshowalter 5/17/01 12:57pm ... MD4044 rshowalter 5/17/01 12:57pm
MD4045 rshowalter 5/17/01 1:06pm ... MD4046 rshowalter 5/17/01 1:19pm
MD4047 rshowalter 5/17/01 1:21pm ...

And, most personally:
MD1080 rshowalter 3/16/01 1:32pm

gisterme - 09:24pm Jul 16, 2001 EST (#7107 of 7109)

rshowalter wrote ( rshowalter 7/16/01 6:00pm ): "...The lasar approaches can't work at all..."

We'll just have to agree to disagree on that...

gisterme 7/2/01 3:25pm

gisterme 7/2/01 6:03pm

gisterme 7/3/01 7:24pm

gisterme 7/5/01 6:33pm

gisterme 7/6/01 8:13pm

gisterme 7/9/01 7:56pm

rshowalter - 09:27pm Jul 16, 2001 EST (#7108 of 7109)
Robert Showalter showalte@macc.wisc.edu

Back about that in the morning. Nice to see that you're making definite points.

lunarchick - 09:30pm Jul 16, 2001 EST (#7109 of 7109)
lunarchick@www.com

Bye!

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