Re: Death Ray Analysis

Are you serious? Where do you expect to see advanced military hardware, at Walmart?

Why, because you don't understand it? Or, if you do, exactly why is it sure to be "bogus"?

Maybe when the working guys are back on Monday, there will be something better to chew over.

Fred

Yeah, ain't it great?! (93 today)

Sure. It's called an RF pumped CO2 laser. A decent commercial unit would kill a snake in two seconds... cut it into pieces. But there are cheaper ways to kill snakes.

the

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Expecting the same...a great day for hard labor! (me, digging 5' deep, rooting out tree roots)

-- Cheers, James Arthur

Well... The Germans sure failed to appreciate the importance of CH radar as part of the British fighter command and control system, that seemed magically to put fighters in the right place, else they would have attacked the stations more intensively than they did.

WWII was, to a large part, won by deception and disinformation. A lesson that has been well learned in later conflicts, by both sides.

Not exactly *hard* labor, but I'm cleaning out the garage (in process of moving the junk) this weekend.

It was a scorcher in San Francisco yesterday. At one point I was truly tempted to remove my sweatshirt, and I actually drove a mile or so with the car windows partly down. Luckily, the heat wave passed: it's

Darn you! I was doing a good job at forgetting that I'm supposed to do the same thing, and you go and remind me.

The irony was that at least at the start of WWII the Germans had far better radar dish antennae and transponders - sufficiently good and steerable that at least one confiscated Wurtzburg dish was still in use by radioastronomers up until the 1970's. Very well engineered they were.

The invention of the cavity magnetron changed things completely - especially once they were being mass produced for us in the USA.

Mainly it was won by code breaking and mistakes by the enemy.

Including key phrases in ever message is a potentially fatal cryptographic weakness. The work Turing did on this was so significant that it has only recently been declassified and it is *still* relevant.

If you know that your adversary will always include a certain phrase in every message you have a much better chance of breaking it.

That's a typical mid-winter day! ;-)

I gotta paint it next. I may start next weekend. It'll be too hot during the day, so it'll take a few days.

Particularly when it's in a header, or at least in a known position. Sending the same text in the clear and enciphered wasn't real bright, either.

Plus a whole lot of dead Russians. The English did a whole lot of cool stuff, but only a small fraction of the actual dying.

Cheers

Phil Hobbs

Pretty brilliant cover story IMHO.

"Glomar Explorer" is still my favorite. I fell for that hook, line, and sinker in the 70's. Every science magazine was running it, and even oil companies felt pressured to drop a lot of money into mining manganese nodules or miss out on the gold rush.

LOL!

I bet you go down to the wharf and watch the tourists in T-shirts and shorts enjoy the weather.

John Larkin wrote in news: snipped-for-privacy@4ax.com:

cut You find it in your fiber optics tv/internet/phone connection. Nothing wrong with modulating anything onto an ifrared beam. And you might be able to kill a bacteria with it(with or without modulation). No modulation will ever make carrier wave less or more dangerous. Sorry to disappoint all those SF lovers(me included)

Does this put an end to the theory that driving SUVs heats the planet?

We can put, say, 5 mw into a 62 micron fiber with a cheap laser. That's almost 2 megawatts per square meter CW. That should toast some tiny critters. Serious butterfly lasers on single-mode fiber will be orders of magnitude more.

You could probably do chemistry at power densities like that.

the

No. Driving SUV's does heat the planet, but indirectly, by trapping a bit more of the radiation that comes from that star at the centre of the solar system. It's all re-radiated eventually, but driving all those SUV's means that the bit of the atmosphere that is doing the re- radiation ends up a bit further above the ground, and us mortals stuck at ground level experience warmer days (and nights).

Your local university could teach you to do the heat transfer calculations yourself - the underlying theory is well-established and works remarkably well, though predicting day to day weather is a bit more difficult.

-- Bill Sloman, Nijmegen

You can hit specific vibrational modes of some molecules. Putting in enough energy to break a specific bond is rather more difficult.

You could - in theory - heat up a specific bit of a molecule to selectively speed up one particular reaction path to get more of a particular reaction product, but if anybody is doing it in practice, it hasn't got into the small part of chemical literature that I get to see.

Apparently Physics Today published something on the subject in 1980

-- Bill Sloman, Nijmegen

How much can you shove into an average fiber before it starts burning and tracking (optical Kerr effect) and stuff?

Tim