Actually the speed of light depends on the medium the light is moving through. The speed of light in a vacuum is considered to be the upper limit because there is no resistance to the passage of the light in a perfect vacuum (which doesn't exist, except in some politician's heads).

 

I have a question too, If you were travelling the speed of light and then turnd on your headlights, would they work (project out in front of you)??????

 

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But how would those not moving at the speed of light see it? Twice as fast (i.e. twice the frequency). I think Doppler chimed in on that (train whistle is high pitched coming towards you and low pitched pulling away). What would be really interesting to consider is what if you were backing out of your driveway at the speed of light with your headlights on. The light would be emanating from the headlights at the speed of light but being drawn away from the observer at that exact same speed....

 

From Einstein:

"We will raise this conjecture (the purport of which will hereafter be called the "Principle of Relativity") to the status of a, postulate, and also introduce another postulate, which is only apparently irreconcilable with the former, namely, that light is always propagated in empty space with a definite velocity c which is independent of the state of motion of the emitting body."

Humph. Far be it from me to tangle with Einstein. But if doppler applies to electromagnetic signals such as are used in radar, and light is just the upper end of the known electromagnetic spectrum...

This guy, on the other hand, has no qualms about tangling with Einstein (he's dead afterall) on the very subject:

http://users.powernet.co.uk/bearsoft/P5Nedmb.html

 

Sort of asked and answered . . .

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With regard to light being "drawn away" you make it sound as if it were almost like a gravity effect, and I don't think speed creates gravity (although how would I know, I've never travelled at the speed of light . . . well, maybe I have, but I just haven't caught up with myself who already travelled at that speed . . . oh never mind) . . .

Your posit is based on the observations of an observer looking at the vehicle traveling in one direction at the speed of light and shining headlights in the opposite direction. First, although I'm basically pulling this out of my ***, I'm gonna assume that someone traveling at the SOL would not even be visible to an outside observer, regardless though, since the light source emanated at one specific point and that source would be traveling away from you at 186000 MPS and the light beam from the headlights would be traveling in the opposite direction at 186000 MPS, then for an instant, the observer would see a flash of light seemingly suspended in one spot . . .

After that though, the light particles, or waves, or whatever we think they are (maybe their Wavticles or partiaves) would continue to move "forward" and would then advance (which you wouldn't see so that light flash that seemed to just hang in mid-air for a bit would vanish).

That's my guess and I'm sticking to it.

 

Based on what I know about the Doppler effect, I'm gonna agree with you on that. I read Einstein to say otherwise (that the speed of light was not affected by the speed of the source it was emanating from), but maybe I just couldn't even follow what he was saying to begin with.

If a train blows a whistle, from the observer's perspective, there will be one tone if the train is standing still, a higher tone if the trains is coming towards the observer (the speed of the sound waves and the speed of the train are additive), and a lower tone if the train is pulling away (the speed of the sound waves and the negative speed of the train are additive). The same concept applies to police radar (the speed of your car adds to the frequency of the signal being bounced off of it) and also weather radar. Don't know why light would be any different in this regard, but I've never actually tried to understand Einstein to begin with. He's way beyond the realm of simple common sense and logic, which is about as far as I can carry things...

 

Don't forget, Einstein also said (and I can't remember if this was in writing or whether he said it over beers while drunk in a local bar) that while his theories said you couldn't travel at the speed of light, he believed that actually it could be done, if not exceeded. (By the way, this may be a secret, so keep it between you and me).

And actually, I'm gonna have to agree with him on this (unless I don't).

The speed of light is a set speed (for our purposes here in this discussion) aprox 186,000 miles per second. I don't care what they say . . . There are numbers past 186 K and there are speeds past that too. I don't wanna hear about energy needed exceeds available . . . blah blah blah. Yeah, based on what we "know" now that's true . . . but here's a dirty little secret no scientist wants to think of . . . we humans DON'T. KNOW. §HIT. Science is mostly guess work, not much different that the fantasies told in fairy tales. How often do you see "Scientists say this is such and such a way!" only to say a few years later "Wait, we were mistaken due to an error in our input...it's actually this way instead!", only to come back again a few years later to say "Wait...this is absolutely the correct answer...it's absolutely THIS way!". Yeah, whatever. Science = best guess with the information available at the time. They said man could never travel past 100 miles an hour or else he would disintegrate . . . and we all know that's just §hit. (Everybody now knows that we don't disintegrate till we reach 358 MPH!)

Will we eventually be able to travel faster than the SOL? Yup . . . and it might be in the manner of conventional travel, or it may be in a manner we haven't even dreamed of yet.

As for measuring light like sound waves . . . I think that's like comparing apples and Godiva Chocolate Cheesecake. I don't think you can base your assumption of one on the properties of the other. Unless you can, then I retract that statement.

 

If you were going the speed of light and you turned on your lights, the light would be would 2x the speed of light. Just as if you were driving your truck 55 MPH and you threw a baseball out of it at 55 MPH it would be going 110 MPH.

 

 

All good common sense as far as I'm capable of. However...

I was careful to point out that the Doppler effect applies to sound waves as well as electromagnetic waves (radar, etc) -- AND -- that light is part of the electromagnetic spectrum. The underlying principle applies equally, and sound waves have been used as an analogy for beginners in RF theory since the dawn of modern "science."

So I'll assume you do, in fact, retract that statement. Unless you prove otherwise, in which case I'll retract my assumption regarding your potential retraction regarding your assumption...

 

Good Lord, I hope this doesn't mean you're playing with metal objects tied to kite strings in an electrical storm!!!

However, now that I think about it, that could be a good way to experience LIGHT in it's most pure form, which could provide some insight or rather enlightment to light and its physical properties, which may imbue in you an understanding of the speed of light and what happens when you flash the headlights on in the opposing direction of travel . . . wow . . .this is cool!
*Kobi™ searces for a kite, a key, and a storm*

As for retracting my statement, or question, or whatever it was . . . consider it retracted until notified otherwise.

k-

 

Hee hee. No, I gave that up years ago. Ran out of string.

There was a bit of double entendre there. Ben was known to play with "light" but was also famously quoted as saying something to the effect of:

"Beer is proof that God loves us and wants us to be happy."

He truly was a man of enlightenment and discovery.

 

Ben Franklin. The only President of the United States, who was never President of the United States. - Firesign Theatre.

Didn't Franklin also come up with the "Beer - Helping Ugly People Have Sex" Poster?

I think he did . . . hold on, let me look . . .

Yup

 

Handsome devil, that one...