according to the theory of relativity its Impossible to go the speed of light because if you spend any time at 1.0c (the speed of light) you are compressed infinitely and one year to you will be infinity to everybody else. Why can light itself get away with this? Wouldnt it not even exist to us? Can someone tell me what im missing?
2006-08-05 12:54:41 · 6 answers · asked by Anonymous in Science & Mathematics ➔ Physics
If light has no mass how would a laser work, it's just compressed light right.
2006-08-05 13:05:08 · answer #1 · answered by Sean 7 · 0⤊ 0⤋
Light is merely a part of the electromagnetic spectrum. Just like radio waves or microwaves (or infrared or ultraviolet) And all electromagnetic waves travel at 300 million meters per second in a vacuum (actually it's a hair slower, the best number measured to date is 299,792,458 meters per second)
The reason that they travel at that exact speed has to do with a couple of things called the 'permitivity' and 'permeability' of a vacuum (or, as it's more commonly called, 'free space') I can take you there, but I don't think you'd enjoy the trip all that much since you'd be up to your eyeballs in mathematics for most of it.
It's kinda like the speed of sound being controlled by such things as atmospheric density (air pressure), temperature, and humidity.
And, in fact, light doesn't always travel at the 'speed of light' (except in a vacuum) In all other materials, it travels considerably slower. The exact amount by which it is slowed is controlled by a thing called the 'index of refraction' of the material. It's the reason that a stick shoved into a pool of water appears to be 'bent' at the surface.
And no, the Theory of Relativity says no such thing. What it says is that it's impossible to accelerate anything to the speed of light, and that information cannot be transmitted from point 'A' to point 'B' any faster than the time it would take a photon to get from point 'A' to point 'B'. (What it actually says is that space and time are just two different aspects of the same thing and that, depending upon your inertial reference frame, measurements may be time-like or space-like with respect to an outside reference frame)
What you're missing is a couple of years of Calculus, a year of linear algebra, a year (or two) of ordinary and partial differential equations, a year of complex number theory and analysis, a year (or two) of n-dimensional vector analysis (and tensor analysis), and *then* (now that you've got the math requirements out of the way) a year of Special Relativity (and it's relationship to Maxwells Field Equations), and a year of electromagnetic field theory.
And no, laser light is not 'compressed' light in any way, shape, form, or fashion. Electromagnetic waves may also be thought of as particles (called 'photons') each of which oscillate at some particular frequency. The light from a laser is special since each photon not only oscillates at the exact same frequency as all of the others, it also oscillates synchronously (we refer to it as 'in phase') with all of the others. This gives laser light some rather unique properties.
Lastly, since a photon has energy (as is related to Planck's Constant) it *does* indeed have what is called a 'rest mass'. Planck's Constant is pretty small and the rest mass of a photon is *real* small. But it's *not* zero. In fact, the 'pressure' of sunlight is quite easy to measure in orbit. It's generally believed that it's the pressure of starlight that first begins to 'push' large clouds of interstellar gas and dust together to form new stars.
Doug
2006-08-05 21:38:16 · answer #2 · answered by doug_donaghue 7 · 1⤊ 0⤋
As I understand it, light is not mass, and the restrictions that you are referring to only apply to entities that have mass. The light is only "travelling" in the sense that the wave of energy transfer "travels" at this speed.
Also, you can have phenomena such as space stretching faster than the speed of light, so that the galaxies receed from us at speeds faster than light, yet they are not locally exceeding the light speed liimit. Space is not mass, therefore, it can stretch at speeds faster than light.
2006-08-05 23:57:39 · answer #3 · answered by dexarouskies 1 · 0⤊ 0⤋
light has no detectable mass (yes that's important), and also, there's a reason its called the speed of LIGHT....
2006-08-05 20:03:34 · answer #4 · answered by Anonymous · 0⤊ 0⤋
Light has no mass and therefore there no resistance to its motion.
2006-08-05 21:28:28 · answer #5 · answered by meno25 2 · 0⤊ 0⤋
simple, light has no mass...
2006-08-05 19:58:16 · answer #6 · answered by mojopez 4 · 0⤊ 0⤋