Why is the speed of light so high? ?

Question

Why is the speed of light so high? ?

Answer 1

Why not?  It is what it is.  Asking why isn't meaningful because the speed of light is a basic characteristic of the Universe for which there is no known cause.

Here are a couple of articles that discuss physical constants.

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

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

Answer 2

It just is, "why" questions are invalid when discussing inanimate objects.

Answer 3

No one knows WHY it is so high, but it is.

Answer 4

It appears high to us, because we are slow.

We are slow because we powered not by nuclear energy, but by chemical reactions, like burning fats.

Answer 5

It is what it is. Whether that is high or low is a matter of opinion and is of no consequence.

If the value of c were very much lower, the world would look quite different, as everyday activities would have to take special relativistic effects into account.

Answer 6

One answer is that it isn't.  When physicists work out equations in relativity they often set the speed of light to one: c = 1.  This makes the equations more tidy.  It amounts to defining natural units of measurement in which the speed of light is exactly one unit.  For example, if the second is kept as the basic unit of time, then the unit of length must be equal to exactly 299792458 metres.  This unit is called the light-second because it is the distance travelled by light in one second.  The speed of light is then one light-second per second.

This is not a complete answer.  The speed of light is high when measured in our standard units such as metres per second or miles per hour.  Those units are defined by arbitrary conventions which have their roots in ancient ways of keeping time and measuring distances.  It is probably no accident that the second is about the average duration of a heart beat and the metre or yard is the distance of one human step.  So the real question is "Why is the speed of light so high in terms of familiar every day measurements?" or "Why are the speeds at which we normally move so slow compared to the natural units in which the equations of physics take the most tidy form?"

These are very meaningful questions but ones to which we have only partial answers.  The speeds at which we walk and live are limited by the amounts of energy E available to us from the chemical processes which drive our muscles compared to the amount of mass m which is to be moved.  Kinetic energy at low speed is given by the formula E=(1/2)mv2.  So the order of magnitude of velocities we obtain when powered by chemical energy might be given by the square root of E/m.  Actually it will be much less than that because we are very inefficient in our use of energy, allowing most of it to be released slowly and dissipated as heat.  Our speeds might also be related to the strength of gravity on Earth g = 9.81m/s2 in relation to our own size.  It is no coincidence that g takes a moderate value in conventional units, unlike c.

It is a consequence of relativity deduced by Einstein that the amount of energy available from a mass m is given by E = mc2 so the question now becomes (in part at least) "Why is so little of the energy of matter available in the form of chemical energy?" If our metabolisms worked using nuclear reactions instead of chemical reactions we might move much faster (other factors permitting) and then our units of length and time would be different, and the speed of light would not seem so high.  These relative scales of energy are determined by such parameters as the coupling constants of the natural forces and the masses of particles.  We know from observation that these take values which vary widely in scale over many orders of magnitude.  We do not yet know why this is.  It may be that the values are arbitrary and their differing values have to be put down to something ontological such as the anthropic principle, or it may be that they are determined without ambiguity from a unified theory of forces which split naturally at different scales.  The strength of gravity on Earth comes from similar parameters in cosmology and similar principles may apply to the question of why hospitable planets have moderate gravitational fields.  Until more is known about the fundamental parameters and how they derive from deeper principles, a complete answer cannot be given.

Answer 7

The speed of light is barely connected to the speed of the electrons in orbit of the atom's nucleus.  Think about you throwing an orange from your dad's car window when traveling at 60mph.  The orange will be projected at that same speed.

In terms of overall view, the speed of light is not "so high", it takes many thousands of years just to cross our galaxy diameter.

The thing is that all other speeds we use to observe and measure are very slow compared with it.  :)

Answer 8

The speed of light is the only absolute speed in the Universe. It is THE speed, and all other speeds should be measured relative to it. As a matter of fact, a meter is defined as the 1/299792458 of the distance travelled by light in 1 second in a vacuum.

We should not question why the speed of light is so high, then, but why everything else is so slow. Well, here's part of the answer: Special Relativity is the only logical conclusion one can reach once one assumes the constancy of the speed of light, and it explains that you cannot accelerate to the speed of light (and, by extension, beyond the speed of light) with any finite amount of energy.

Why then do most objects not even approach a fraction of the speed of light? The answer is that most processes simply do not provide enough kinetic energy to accelerate objects to relativistic speeds. Remember K. E. = 1/2 mv^2, hence increasing velocity tenfold will increase K. E. 100-fold.

Answer 9

At this time there is no over-arching theory that tells us things like why the speed of light is what it is.  

But for that matter we don't know  why the gravity force between two objects is as strong as it is or why an electron has as much mass as it does.  All these things involve a number which, as far as anyone knows, has to be measured and can't be worked out from just starting with math (like pi can).

Maybe there will be a theory in your lifetime that tells you the answer to these questions, and maybe they won't be worked out for a very long time.

These questions are deep and mysterious and will take a lot of clever thinking and experiments to work out.