Why the speed of light is?

Question

Why the speed of light is constant, and what is the speed of darkness? thanks.

Answer 1

Firstly, please allow me to substitute your term "speed" for the more accurate term "velocity".

All particles and waves have an intrinsic velocity in a vacuum. The subatomic particle which makes up light is the photon. The photon travels at an average maximum velocity of 3x10^8 m/sec in a vacuum. For the exact numerical speed, here is a good source

http://en.wikipedia.org/wiki/Speed_of_light

but for the purposes of almost all calculations, 3x10^8m/sec is used. There are physical forces which can slow down the speed of light, and the chief force is gravity.

Darkness is the absence of light, and therefore, the absence of any photons. Therefore, the concepts of speed and velocity are not applicable.

P.S. There is only one particle theorized to be faster than the speed of a photon, or more aptly put, faster than the speed of light. That subatomic particle is the "tachyon". It is further theorized that , because it is travelling faster than the speed of light, it is also travelling backward in time.

P.P.S. Many of the theories in physics are derived from solutions to various "so-called" unsolvable problems derived from math theory. In this sense , physics and math go hand in hand. Therefore, many physics theories are simply supported by math equations until a real life proof can be generated, characterized properly, qualified, and quantified. The problem here is that just because a math equation may have a solution , it alone BY NO MEANS is proof in and of itself of the existence of subatomic particles and physical phenomenae. It can only be used as a measuring stick,of sorts, in order to look for the existence, and therefore, FORMAL PROOF of such phenomenae.

Answer 2

One suggestion as to why the speed of light is constant is that all particles are moving at the speed of light in the 4-dimensional space-time continuum. Normal particles have most of their velocity in the time dimension, so we move through time at a standard speed and through space very slowly. Photons, without mass, have all their velocity in the space coordinates.

This way of thinking helps understand why time slows down as velocity increases. Think of a racecar racing straight north at the Bonneville salt flats. An 11-mile run takes some amount of time. If there is a strong east wind the car might go at a slight angle to the northeast, the hypotenuse of a right triangle, which is actually a longer route than the straight one. The extra time this takes represents the fact that the velocity is divided between the 2 different directions, so the time it takes to go the course north is slightly longer, even though the speed is the same.

As for the speed of darkness, what is the speed of quiet? Darkness is the absence of light, so it moves at the same speed that light moves at.

Answer 3

In round numbers, the speed of light is 186,000 miles per second or 300,000 kilometers per second.

Nobody knows why the speed is constant, but it is. That is a measured fact.

There is no such thing as the speed of darkness. It would be like saying that the speed of sound is 700 miles per hour so what is the speed of silence. Darkness is just the absence of light. I guess you could say that if the Sun suddenly went dark, that darkness would spread out from the Sun as the last rays of light moved away, and that would happen at the speed of light, but it isn't really darkness moving, it is light.

Answer 4

First off, the speed of light is constant ONLY in a total vacuum. In a total vacuum, the speed of light is constant because the particles that make up light have no mass, therefore aren't subject to the forces that cause the speed of other things to slow down or speed up.

Answer 5

Particles on a wave of energy move so fast that I believe we really do not know how much they slow down or speed up and on what scale. We just know a certain speed based on scientific methods, technology , instrumentation today. It appears we do know that gravity can bend light. The speed of darkness is the same because it has some of the wave particles in it that does in the light we see. As for the speed of nothing. It is 0, or just drifts with time.

Answer 6

well there is no speed of darkness. And the speed of light is constant because it's dependant on your perspective, as in it always travels at the same speed to or from you.

Answer 7

Darkness is not a tangible thing, it rather is like cold, it is the absence of light. The speed of light is a constant only in reference to observation. This was discovered by the double slit experiments with electrons and photons.
Check it out for yourself...
http://video.google.com/videoplay?docid=-4237751840526284618&q=quantum

Answer 8

150,000,000 miles per hour

Answer 9

3.8m/s