New York Times on the Web Forums Science

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.

gisterme - 06:36pm Feb 10, 2002 EST (#11437 of 11476)

rshow55 2/10/02 6:05pm

"You're exactly wrong, gisterme , when you say:

"If we had to rely on "open literature" to limit possibilites in scientific/engineering discussions as to what's possible and what's not, then we'd still be using stone tools."

What is possible is informed by what has gone before..."

Not true. Necessity is the mother of invention. Necessity may be revealed by what has gone before but not what is possible. Past experience does not limit future possibilities.

"...And on these issues, a lot has gone before -- a lot is well known..."

But if the first maker of a stone tool had to rely on the "open literature" to figure out whether it was possible or not, guess what? We wouldn't even have stone tools yet. So your conclusion of "exactly wrong" fits itself better than it fits my statement.

That the open literature WRT MD we've been showing you lately, (the stuff you've been ignoring), is well known I must agree. It proves the feasaibility of the ABL. You're just in denial about it. However, much of that stuff you've been denying wouldn't have been availabe say, 40 years ago when laser sceince was in its infancy, would it? Nope. How do you suppose the "open literature" ever gets anything added to it? How does it advance? You don't have a clue, do you?

Don't try to put the cart before the horse, Robert. That's the formula for never moving ahead. We'd be a stagnant feudal society at best if history had followed your advice. More likely, we'd be like monkey troupes or perhaps even herd animals.

gisterme - 06:39pm Feb 10, 2002 EST (#11438 of 11476)

rshow55 2/10/02 6:13pm

"...You're showing your ignorance, gisterme..."

Oh??? How so? Care to 'splain that to me?

I'm going to eat while you try to figure out how to handle this particular overload you've taken on...

Back in a bit.

rshow55 - 07:05pm Feb 10, 2002 EST (#11439 of 11476)

In gisterme 2/10/02 6:07pm , gisterme seems to find it "strange" that a hand held calculator can calculate sines and cosines well - - - or perhaps finds it "strange" that sines and cosines are the functions to look at for laser accuracy.

sines and cosines are calculated - - like most other functions that machines actually calculate -- on the basis of "infinite series" - series that go on and on, but that are approximated very well with a finite (often small) number of terms.

The sine series and cos series are both simple -- a hand held calculator calculates them well and easily - to the number of significant figures the display has. For an angle x , in radians, the series are

sin(x) = x - x^3 +x^5 - x^7 + x^9 . . .

cos(x)= 1 - x^2 + x^4 - x^6 + x^8 . . .

(where ". . ." means "and so on, with additional terms in the same pattern". For small values of x, the first few terms are very good approximations for the sine and cosine series.)

Lasers work because light organizes itself, by reflections between mirror surfaces, coherently -- not perfectly in the mathematical sense, but with the waves close to perfect phase. If the cosine of the angle by which the mirrors depart from parallel is approximately 1, the lasing works.

The angular accuracy lasing needs is much less than the level of angular accuracy needed so that optical imperfections in the laser can be ignored for the purposes of ABL.

rshow55 - 07:11pm Feb 10, 2002 EST (#11440 of 11476)

Gisterme says:

"We'd be a stagnant feudal society at best if history had followed your advice. More likely, we'd be like monkey troupes or perhaps even herd animals."

My advice was that we consider, carefully, what can be done in the open literature in well developed fields such as optics, vibration control, adaptive optics, and control theory and applied knowledge about controls. And consider other technical information, long established, as well.

An engineer with a name and a PE ticket to lose would be embarrassed to deny that.

We build on what has gone before -- of course we expect to make advances. But we want to use what is known, and not repeat mistakes.

mazza9 - 07:19pm Feb 10, 2002 EST (#11441 of 11476)
Louis Mazza

Okay so I haven't left yet. I agree with RShow55. Nothing is perfect in this world, save RShow55!

He doesn't need an umpire. His obtuse shenanigans and stalling and obfuscating wears everyone down until he is the only participant left at this forum.

Of course a real umpire might just look at him and scream:

YOU'RE OUTTA HERE!

Say, didn't Scott do that already?

Happy Mardi Gras!

Lou

rshow55 - 07:23pm Feb 10, 2002 EST (#11442 of 11476)

In a world as imperfect as the one we live in, we shouldn't fund projects that require impossible degrees of perfection when there are other alternatives (interdiction, and diplomacy, to name two) that are much more sensible.

(34 following messages)

New York Times on the Web Forums Science Missile Defense