How is it that the speed of light is the fastest speed there is? There's gotta be something faster. Can anyone explain to me how this is possible? Correct me if I'm wrong here but: I think light is slowed down since it is still part matter, can there be a pure energy (not counting the electrons mass)? If so, wouldn't it be able to move faster? Or is the mass in light only the electrons mass?

The Speed of Light (usually refered to as c) the speed that Electromagnetic radiation propogates (light is EM radiation). Light (or any other EM radiation) is not made of electrons or any other matter. It is made up of Photons, which are massless particles. In Quantum Mechanics, photons are a quanta (or discreet amount) of energy. Photons are pure energy. As for why c seems to be a speed limit, no one really knows.

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Some try to tell me, thoughts they cannot defend,... - Moody Blues.

What is the fastest something could ever go? A photon travels to wherever it was sent in zero amount of time (from its point of view).

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Lighten up! This is a stellar board! Author: duh.

"The Sun, with all the planets revolving around it, and depending on it, can still ripen a bunch of grapes as though it had nothing else in the universe to do..." Author: Galileo supposedly.

We look at everything, and don't ever see anything faster.

Why?

Why shouldn't it be possible?

What does "part matter" mean?

"Slowed down" in comparison to what?

If light were "part matter", why would it be "slowed down"?

What is "pure energy"?

What do electrons have to do with any of this?

Depends on what you mean by "pure energy".

There is no mass in light. Photons are massless particles.

What do electrons have to do with any of this?

-- Jeff, in Minneapolis

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http://www.FreeMars.org/jeff/

"The other planets?
Well, they just happen to be there, but the point of rockets is to explore them!"
-- Kai Yeves

The speed of light in a vacuum is the fastest speed that is possible, according to special relativity theory (SR). If SR is correct, then it will be impossible for anything to travel faster, as measured in your laboratory, than light does in a vacuum. If SR is incorrect, then maybe the speed of light in a vacuum is not the fastest possible.

Why?

As far as we know, it is necessary to correct you. Light is energy as pure as we know how to understand the words "pure energy". It is not matter, and has no matter in it.

Now it should be stressed that it is not "the speed of light" that is the limit, it is "the speed of light in a vacuum". It is possible, for instance, for a particle to travel faster through glass than light does, in which case it will emit Cherenkov radiation.

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Don't try this at home - We're what you call "professionals" - MythBusters.

Here's another angle on it. The fact that photons exist is not necessary to have special relativity, we would have discovered it anyway (via particle accelerators). So you can think of it this way. It turns out that when objects are moving very fast, relative to you, time slows down for them, relative to you. The faster they go, the more their time slows down, relative to yours. Although that's weird enough, here's the even weirder part-- that process reaches a limit, such that the closer the object gets to a particular speed (which is c), the more time slows down until it is almost completely stopped. This is what makes c special, the fact that photons actually move at c is related to the fact that they have no rest mass (as has been pointed out), but again the existence of photons is not a necessary part of the specialness of c, it comes from the limiting speed at which time stops completely, and can be determined from normal matter.

If the photon experiences "no time" at its speed of light due to relativity, then to go any faster you would have to have left before you arrived and therefore be in two places simultanously. Which is impossible.

Like max8166 said:

Yes. Wherever you go, there you are; and not, wherever you (photon) go, there you were.

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Lighten up! This is a stellar board! Author: duh.

"The Sun, with all the planets revolving around it, and depending on it, can still ripen a bunch of grapes as though it had nothing else in the universe to do..." Author: Galileo supposedly.

Doesn't this tie in with the principle that everything in the universe is traveling through spacetime at the speed of light? Photons in a vacuum happen to be traveling entirely through space and not through time. Other objects, like people sitting still (relative to the Earth), are traveling entirely through time with no spatial vector. And still other objects have some combination of a spatial vector plus a time vector that "sums" to c.

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How many times have you been about to grasp the truth when somebody else suddenly yanked it out of your reach?

Yes, that is a nice way to look at it, though the "sum" is a rather bizarre one.

Bizzare? How so? Perhaps I misunderstand special relativity. But, here's a small quote from Brian Greene's The Fabric Of The Cosmos that gave me the idea:
I don't pretend to know the specifics of the math involved, but it seems like Greene is refering to some kind of sum.

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How many times have you been about to grasp the truth when somebody else suddenly yanked it out of your reach?

I think that makes the most sence to me. I'll have to remember that one. Thanks for all the replies guys, I was just confused.

Also, I've got to keep in mind light doesn't travel through a vacuum so that's why it's slowed down. So, does this mean that using lightyears as a unit of measure can be inaccurate? I suppose if there's more matter in one area it would take longer for the light to get there than if it just traveled through a vacuum. Or is the amount it's slowed down so small that it doesn't matter? (Although, after billions of lightyears of distance I would think it would change our calculations quite a bit.)

Quantum dis-entanglement is "instantaneous," although I'm not sure that really counts as a "thing."

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PW -- Plant Whisperer

He is, but it is neither an arithmetic sum nor a simple vector sum, it is a more complicated form than either of those.

Yes! Any math that has to handle more than 2d becomes so complex that even our latest super computers can't cope with it.

How odd, then, that I seem to be able to use spherical trigonometry to calculate 3D positions, using just pencil, paper and trig tables. It just takes a minute.

Grant Hutchison

[quote=Tim Thompson;802770]snippet...The speed of light in a vacuum is the fastest speed that is possible, according to special relativity theory (SR). If SR is correct, then it will be impossible for anything to travel faster, as measured in your laboratory, than light does in a vacuum. If SR is incorrect, then maybe the speed of light in a vacuum is not the fastest possible.

Tim. True and no argument. I believe SR has been shown to be true millions of times at the least in particle physics . The speed of light in a vacuum is identical to the speed of light in the neutrino sea, since no vacuum may be emptied of it. When posts are made to the effect of conceptualizations of the vacuum, they often seem to suggest that space-time devoid of solids liquids, gases, and plasmas, is empty. It's not. The words vacuum and empty are mutually exclusive...(there's also the ZPR)...Pete.

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A third rate theory forbids
A second rate theory explains after the fact
A first rate theory predicts...A. Lomonosov

Since neutrinos interact only by means of the weak force, they are totally irrelevant to EM radiation.

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Any day you wake up on "the right side of the dirt" is a good day.

T. Anderson