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ArcticMyst Security by Avery

speed of light

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what would happen if we could sqeeze a laser like a garden hose and make the electrons and photons pass through a smaller opening at the same volume. would the laser exceed light speed? if so would the power of the laser reach astronomical proportions?
 





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Proctor

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The speed of light is constant.

Anything past the speed of light is infinity.
 
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randall158 said:
what would happen if we could sqeeze a laser like a garden hose...

I'm assuming you are not talking about physically squeezing the actual laser device, as that would likely destroy it, or otherwise alter the conditions that meet the requirement for it to work in the first place such that it would no longer lase. As for "squeezing" a laser beam, that's what a lens (or a curved mirror) is for. ;)

As Proctor said, the speed of light is a constant and would not change, but

randall158 said:
...and make the electrons and photons pass through a smaller opening at the same volume.if so would the power of the laser reach astronomical proportions?

There is a limit to how much energy you can fit in a small area, especially if a gas, liquid, or solid is present. Focused megawatt laser pulses in air can easily ionize the air at the focal point. In a perfect vacuum you can reach much higher powers.

Even if you could raise the power of a laser indefinitely, eventually you will reach a point where the materials it is made with, and/or the lasing medium itself, cannot handle the energy, and POP!
 
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SenKat

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To effectively answer this, you gotta dig down to laser basics - if you limit the aperature size, all it would do is limit the number of excited photons exiting the laser. Lasers work (very basically) by a photon bouncing off of excited electrons - which charge that photon, and emit a clone of the photon as well. the photons can be emitted in almost any direction, but if a photon hits the electron at a specific angle, it also exits (along with its' clone) at the same angle. all the now highly charged particles of light are going in one direction, maybe even bouncing off of 2 mirrors - one with 100% reflectivity, and another that reflects some, but allows others to pass - thus continuing the chain reaction inside the "lasing" chamber. The photons that come out, can then pass through colliminating optics, filters, etc. BUT there is no way to "squeeze" those photons in order to speed them up.

Long winded, eh ? Anyways, I left out some stuff, and put other stuff in my own order, but that is most likely as simply explained as is possible. I read this on some site that actually went into great detail (on a low-level) to explain it to 8th graders, I think ! Pretty good read - if I can find the link, I'll post it.
 
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Yes, the reason why things go faster when you squeeze them is because when you squeeze a tube of toothpaste for example, your hand repels the tube, which moves inwards, and the toothpaste has to go somewhere, so it goes forward. Toothpaste and the tube are tangible though, so that's easy. With light though, its intangible. You can put your hand in front and cause some to go in your hand, and some to bounce off, but you can't physically affect it like you can toothpaste, so basically you can't speed up light this way (and there are other reasons you can't too). Considering that you wonder about that though, you might be interested in checking out a book from the library about fundamental physics and such. Maybe something particularly geared at electromagnetism.
 




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