Light speed Definition and 317 Threads

What gives light its speed? And why does it travel at c, not faster or slower?

[SOLVED] Zero to Light Speed - Atom's Point of View Atoms in a light bulb filament with house current are heated to the point that they readily emit visible light photons. Three Questions: 1. What is the expected (or virtual) speed of the ELECTRON that emits a photon just as that photon is...

Some day I was driving my spaceship that can go as faster as light velocity. (in year 2175 all of us believe Einstein was wrong). Suddenly, a dumb driver appeared in the galactic highway with a old fashioned spacecraft , and when I reach him I stood behind him wanting to express my angry. To my...

Just was wondering if there was something that pushed photons or if it just a property of light. Also what happens to photons from other stars when they reach our sun?

i have a somewhat elusive question (for me) about light. when you drop a bouncy ball, after it hits the ground, right before it bounces back up, its velocity is zero. correct? it becomes troubling when the ball is replaced with light. when light is reflected straight back to its source, it...

It seems to me that Einstein's equivalence of gravitational acceleration and non-gravitational acceleration, when combined with his constancy of light speed in vacuuo, should yield a constancy of gravitational speed in vacuuo.

the other thread got the lockdown before i got a chance to gather all i could from it <sad> so i guess i have to start a new one. when people say "The speed of light is constant in a vacuum at C or 299,060 kps" (or whatever the freaking number is) what exactly do they mean? from the...

Why does the time on the planet left not appear to slow from the spaceship as it is accelerating at great speed away from the spaceship, relative to the spaceships perception. I mean, could traveling at close to light speed also be viewed as slowing down the spaceship more and more so that the...

Does anyone know whether the expansion of the universe ever exceeded the speed of light taking the early accelerated phase into consideration? If not then the early photons must have bounded back and forth within the boundary of the early universe and a few or maybe many of all photons we are...

Light speed relative to universal speed... HI guys, Just a simple request for confirmation that I have it right. It may seem so obvious to you but to me I just need to confirm with currently held thought ( this forum ) that the photon travels at relativistically zero velocity with the...

Assume that c is the maximum velocity of electromagnetic radiation in an inertial frame of reference centred upon the source of the elecromagnetic radiation. Assign an interface (boundary layer) between adjacent inertial frames of reference such that the velocity of the electromagnetic...

Has anyone an idea why speed of light is constant ? Has this something to do with lack of mass of a photon because I cannnot imagine it to be possible to add speed to something that has no mass. As light emerges from energy fall of an electron, does speed of light have anything to do with...

Like we have learned in school, the ultimate speed is a light speed. Do you believe that? We may be wrong. Let's take an example. There are two objects. They start in the same place and they start moving away from each other. They are traveling in a speed of a light. But isn't the speed they are...

If you are in a spaceship traveling the speed of light and you turned on your headlights what would happen?

I say NO. If energy can be converted to Mass and Mass can be converted to Energy, then, being a layman, what would prevent any object from being propelled to the speed of light without, as I have heard, requiring all the energy in the Universe to do so?

One of the main problems of quasars is: How can an energy equivalent to 100 times that of a normal galaxy, be produced continuously in a region smaller than the Solar System? To solve this puzzle, it was suggested that quasars were not at cosmological distances, but much closer, even within...

I stumbled on an article entitled, “Crash of relativity after Lorenz-Einstein” at: www.worldspace.nm.ru/en/articles/pdf/lor_e.pdf It is written by A.V. Rykov, Ph.D., chief of lab. Of Seismometry at the Russian Academy of Science. What interested me was his assertion that the speed of light...