leroyjenkens said:
Then I guess a better question is why light moves at the speed it does.
It just does. Light has a fixed, constant speed (as postulated by Einstein) which we happen to call c, and which we have defined to an exact value (which I can never remember).
By defining the speed of light we have in essence changed the length of a meter to the distance light travels in 1/c seconds.
So in a perfect vacuum, light moves at C, but in reality it never moves at C?
What do you mean the photons are doing something complicated?
What's the difference between photons and an electromagnetic wave? They move different speeds?
Afaik light never moves at exactly c, that is just the theoretical value that it would travel at if it weren't in any medium.
There's an excellent link somewhere here that explains what photons are doing in a medium that causes light (not individual photons) to move slower than c, but it's pretty complicated and I can't find the link, sorry! Maybe someone else will come along shortly.
Photons and EM waves are two concepts that describe the same thing. Some effects can be best described by regarding light as photons, others by regarding it an EM wave. Sometimes you need both views. As far as I know, both views are consistent.
Electrons don't have mass? So electrons are just energy?
I never said that electrons don't have mass (they do). I said they aren't made up out of anything, by which I meant to say basically that electrons (as far as we know) are elementary particles. A proton or neutron is not an elementary particle because it consists of 3 quarks. An electron does not consist of anything as far as we know.
(Also, energy and mass are equivalent, so you could indeed say that an electron is just energy (with a charge), although I don't know if that is 100% correct...)
(Basically, if you do certain experiments with a proton you can come to the conclusion that it must be made up out of other (3) particles. If you do similar experiments with electrons you don't need it to be build up out of other particles so as far as we know it isn't. Maybe in the future we will discover that even an electron is not elementary, but that is speculation.
It was in response to what he said. He said if a photon is moving slower than the speed of light, it's not a photon.
My question is if a photon DID in fact move slower than C, what would it be, if not a photon?
Photons do not move slower than c, so your question does not make sense. What he meant was that photons always travel at c, they cannot slow down or stop. Your question is basically the same as asking "If a car is not a car, then what is it?"...
I don't want to take the string analogy too literally, but since a string requires something to begin the motion of the string's waves, is there anything that begins the motion of the light waves?
I think there are multiple things, such as accelerating charges or electrons falling back to a lower energy level in an atom.
Furthermore, lightwaves are not "motion". Nothing is physically moving. EM waves are electromagnetic field strenghts oscillating, not substances (such as in a string).
I think what's confusing me is photons. Since they're considered particles, I imagine a small particle of something moving at the speed of light, and if it's moving at the speed of light, I would think something has to CAUSE it to move that fast.
A common "mistake". I suppose by "particle" you see a solid sphere of some material floating around in space. That's not what it is at all. In fact, in quantum mechanics, even electrons, protons, or even large molecules (such as the C60 'buckyball') are actually considered "wave packets", basically a collection of many waves summed so that they are localized at a small (but not infinitely small) position in space. There is always an uncertainty in the position of any object (regardless of measuring inaccuracy) which is caused by the particle actually being a wave (packet).
