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Missile Defense

Technology has always found its greatest consumer in a nation's war and defense efforts. Since the last attempts at a "Star Wars" defense system, has technology changed considerably enough to make the latest Missile Defense initiatives more successful? Can such an application of science be successful? Is a militarized space inevitable, necessary or impossible?

Read Debates, a new Web-only feature culled from Readers' Opinions, published every Thursday.

rshow55 - 08:23pm Jan 22, 2002 EST (#10967 of 10987)

Interesting, gisterme gisterme 1/22/02 7:23pm . Let's consider the example in http://www.phy.davidson.edu/jimn/Java/Coatings.htm that showed of alternating layers of zinc sulfide (n=2.3) and magnesium fluoride (n=1.35). --- Davidson showed a MODEL where 10 layers resulted in 99.9+% reflection. Based on a mathematical model. In that model, what mattered was the thicknesses and the indices of refraction. The model was used because there was reason to be confident of it.

Classical optics is one of the places where theory and experiment agree very well indeed. And the theory, for the reflection case we're dealing with here, depends on thicknesses and indices of refraction. That's not a "feeling" -- it is something you can check. Something others can check, as well.

So, if the thicknesses were the same, and plastics could be found that happend to have the same indices of refraction as the zinc sulfide and the magnesium flouride, then the reflectivity would be the same. You might disagree, but I don't think you should - - this is an area where relationships have been much checked.

Would we agree so far? Not that I've found plastics with an exact match --- so that, if an exact match were required, I might be talking about "unobtainium."

We'd agree that I probably can't find exact matches for the indices of refraction 2.3 and 1.35. So the exact analogy to the case in http://www.phy.davidson.edu/jimn/Java/Coatings.htm doesn't hold.

But the reflective effects still depend only on indices of refraction, and thickness (not, for instance, on whether the materials happen to be glass, or plastic, or silicon rubber compounds, or whatever.)

You disagree with this? It doesn't matter much. The answer isn't a matter of your "feelings" or mine. This is a place where the match between theory and experiment is well established. That can be checked.

Perhaps you're denying that I can find transparent plastics (or flexible materials) in the right thickeness range? Sheet needed would have thicknesses in commercial ranges (microns and tens of microns, not angstroms. ) That can be checked, too, of course.

Neither your feelings, nor mine , will matter to the answer, which is concerned with an area of optics that is well understood.

I haven't ordered the components needed for a demo, yet. Though I've done some looking.

But I'll stand by what I said

"In MD10920 rshow55 1/21/02 2:45pm I showed how, by replacing transparent plastics with different indices of refraction for the zinc sulfide and magnesium flouride that the demo in http://www.phy.davidson.edu/jimn/Java/Coatings.htm happened to choose, "99.9% or 99.9999% reflection for the specific frequency of the COIL system (which has been published) is achievable, without anything fancy, in a flexible, easily made decal."

The more noise you make, gisterme , the easier it is for me be stand up to your "challenge."

rshow55 - 08:36pm Jan 22, 2002 EST (#10968 of 10987)

MD10926 rshow55 1/21/02 7:04pm

Gisterme , I think you should agree. We could save the taxpayers a lot of money.

I stand by
MD10918 rshow55 1/21/02 2:45pm ... MD10920 rshow55 1/21/02 3:04pm

rshow55 - 09:00pm Jan 22, 2002 EST (#10969 of 10987)

MD10912 rshow55 1/21/02 8:45am

mazza9 - 10:37pm Jan 22, 2002 EST (#10970 of 10987)
Louis Mazza

RShow55:

Have you ever been near an ICBM? Are you familiar with its operational environment? Patton is on tonight and I happened to think of you when Patton brushes aside the thoughts of the various defensive positions that must be overcome.

You concoct this reflective decal, (good analysis Gisterme), and choose to invalidate the BMD. Fine but I know that the lasers will work. You have no basis for this reflective decal or that it will adhere to the missile throughtout its operational regime and function as you speculate.

During the Gulf war precision munitions came into their own. Today's capabilities make those of just 10 years ago pale in comparison. Aviation Week recently reported that the Air Force is specifying a new precision munition that can "count the floors to dentonate at the right level. There was those famous pictures of the US munition being guided down an air shaft in Baghdad and exploding within the building. Now you dial a floor and aim your force to a given floor, "26th Floor lingerie, foundation garments, house coats, BOOM!"

I would bet the farm on the Laser and not you smoke and mirrors!

LouMazza

lchic - 12:29am Jan 23, 2002 EST (#10971 of 10987)

The Gulf war - precision missiles? The world gut feeling here is that the supposed 'hits' in peak viewing time - were a 'figment of Elder Bush imagination' .. but the US did try to con the rest of the world! http://www.cdi.org/issues/bmd/Patriot.html http://www.hrw.org/reports/1991/gulfwar/

So the way the 'world' looks at that time is as one of lies re missiles and lies re the supposed 'non' harmful effects of radiation http://news.bbc.co.uk/hi/english/uk_politics/newsid_337000/337027.stm and cocktail injections that still affect the players.

TruthAndWar http://tiger.berkeley.edu/sohrab/politics/truth_in_the_packaging_of_war_news.html

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