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Attiyah Zahdeh
2006-Nov-11, 05:57 AM
Are all the photons in a certain beam always of the same wavelength?

clop
2006-Nov-11, 06:31 AM
Well they are if it is monochromatic light, such as that from a laser. But monochromatic light is rare in nature.

Light from a torch (flashlight) is composed of many different wavelengths. You can split the torch light into the different wavelengths using a prism, just like you can with sunlight.

clop

Mister Earl
2006-Nov-12, 05:25 PM
Clop's got it right. Wavelength = color for the most part. A beam can have different wavelength photons, except if it's a laser. Hrm... wonder if you can use two different lasing mediums and get a mixed laser? Ruby/Argon anyone?

antoniseb
2006-Nov-12, 06:02 PM
A beam can have different wavelength photons, except if it's a laser. Hrm...

People attribute almost magical properties to lasers, when in real life they aren't that special. The light coming out of a laser is not all one frequency. It is typically in a very narrow band of the spectrum, but it i not *exactly* one wavelength. BTW, the photons are also not all going in *exactly one* direction.

Mister Earl
2006-Nov-12, 06:15 PM
Aye. It's not perfect, but it's as close as we can get for now.

Antoniseb, you're good with this sort of stuff... you know how a laser, works, right? Lasing medium, and a half-silvered mirror and all.

My question for you is, is there a half-silvered mirror that would work for Gamma radiation? Is there anything that can reflect, not absorb it?

triclon
2006-Nov-12, 08:49 PM
I was going to say a laser, but someone said they give off a narrow range of frequencies, not just one. Probably the closest thing to a single wavelength would be emission lines in spectra. Of course even the simplest element, hydrogen has multiple emission lines, thus multiple frequencies so anything that gives off light is going to give light off at least at a few different frequencies.

Probably a way to do this would be to excite hydrogen to produce emission lines (or any element really), then run the light through some kind of filter so that only one wavelength could pass through. That would give you photons all of the same frequency.

Other then that, I don't think this kind of thing occurs in nature.

Fortis
2006-Nov-12, 08:52 PM
AT, given the outstanding questions on your ATM threads, can I ask where you are going with this?

antoniseb
2006-Nov-12, 11:04 PM
is there a half-silvered mirror that would work for Gamma radiation? Is there anything that can reflect, not absorb it?
No. A gamma ray laser might be constructed, but it will be with one pass through a group of nuclei in an excited state. Since I can only imagine it as a weapon, I'm not going to say more.

Kaptain K
2006-Nov-15, 07:04 AM
Niven and Pournelle used gamma ray lasers in the novel Footfall. Yes, it was a weapon and each one was a one-shot device, since the exciter was an A-bomb!

Bob
2006-Nov-15, 05:16 PM
An x ray/ gamma ray laser powered by an atomic bomb was a component of the star wars missile defense system in the 1980's. The US conducted a proof of concept underground test but the results (whether laser action took place) were ambiguous. That part of the missile defense system was later abandoned.

BISMARCK
2006-Nov-15, 06:06 PM
I think the wackiest SDI research I ever heard of was $10 million spent to research a "tachyon laser."

It was pitched that you would wait for the Soviets to launch their missles, and then fire the tachyon laser at the launch site so the particles would go back in time and destroy the missles before they were launched.

$10 million sunk into that silliness.

Attiyah Zahdeh
2006-Nov-15, 06:44 PM
I think the wackiest SDI research I ever heard of was $10 million spent to research a "tachyon laser."

It was pitched that you would wait for the Soviets to launch their missles, and then fire the tachyon laser at the launch site so the particles would go back in time and destroy the missles before they were launched.

$10 million sunk into that silliness.


"$10 million sunk into that silliness"!

Were these dollars sunk while adhering to each other?

BISMARCK
2006-Nov-15, 07:06 PM
Say again?

Attiyah Zahdeh
2006-Nov-15, 07:14 PM
Say again?

Whether sunk or burnt, the result is the same!..

BISMARCK
2006-Nov-15, 07:20 PM
http://www.swmcmmj.com/vbulletin/images/smilies/huh.gif

Attiyah Zahdeh
2006-Nov-15, 07:50 PM
http://www.swmcmmj.com/vbulletin/images/smilies/huh.gif
Forget please.

Fortis
2006-Nov-16, 01:31 AM
I think the wackiest SDI research I ever heard of was $10 million spent to research a "tachyon laser."

It was pitched that you would wait for the Soviets to launch their missles, and then fire the tachyon laser at the launch site so the particles would go back in time and destroy the missles before they were launched.

$10 million sunk into that silliness.
Do you have a reference for this? :)

Van Rijn
2006-Nov-16, 01:57 AM
Do you have a reference for this? :)

Beat me to it. I've heard of graser (gamma ray laser) research, but not anything called a "tachyon laser." And you couldn't even call it a "taser." :)

peter eldergill
2006-Nov-16, 02:33 AM
And you couldn't even call it a "taser."

Groan....:rolleyes:

BISMARCK
2006-Nov-16, 05:18 AM
I actually don't it was mentioned in passing on a show on the History Channel or Discovery Channel I think. I've looked for something more about it but haven't had any luck.