Why the speed of light?

Question

Why do scientists say its impossible for anything to move faster than the speed of light. Just because we havent witnessed it doesnt mean it doesnt exist, right?

Answer 1

Hey! That's an excellent question. You brought up a very interesting philosophical term, what we know about the speed of light is partly through empirical observation. However, there are other interesting things to consider.

-the speed of light is a result of many laws of electromagnetism, including Maxwell's equation. It is also important in relativity term. One funny thing to notice is that the important thing is about the number c and not with the physical speed of light itself. For example, if you can make light move slower, that has no impact on the relativity theory.

-If information could travel faster than the speed of light, then causes would happen before their effect. This is all after considering the special theory of relativity.

-One more thing, you know what? Usually speed is relative, but not the speed of light. If two observers are looking at light and one is moving close to its speed, it will not happen that light moves faster for one of them, rather what would happen is that time would dilate for one of them. Imagine that, one of them would take longer to age.

-(ok, this next one is gonna be very simplified. it's kinda more complex than it sounds, but the idea is still there.) Also just imagine, since energy could be converted into mass, how heavy a mass would get as it's approching the speed of light, taking kenitic energy equal to mv^2. It would become progessively harder for that mass to gain kinetic energy, and therefore speed. If you could make a graph of that, the assymptote of that graph would be c! Amazing right?

- In conclusion, don't forget that light has the speed of c in a vacuum only. The implications of light having a speed greater than c are very interesting. You have to kinda understand modern physics to get the supporting details behind a constant speed of light.There have been instances where people have made light travel at a speed higher than c, but it still remains that no information can be travelled at speeds greater than that of light.

Answer 2

The simple answer to this is, basically we have all these equations which are related to eachother and they all seem to be fairly correct.

When the speed of light is exceeded in these equations, things no longer make sense. You get things like numbers divided by zero or things that mathematically don't jive.

It isn't neccisarily true that nothing can occure faster than light, it's thought that the expansion of the universe occured/occures faster than light, but the transfer of information cannot occure faster than light.

What is meant by information, is for example, you. You are a bundle of information. You have a specific amount of mass/energy and when you are flying through space and smash into something, you depart that information onto that object, so to speak. The reaction of the object will be in accordance to the action caused by you.

Now sometimes equations are slightly off, or wrong, or there is a discontinuity, or they're only correct in certain environments. So we cannot...or we should not say in science that something is infallable.

Answer 3

The fact that nothing can travel faster than light is a logical outcome of the observation that every observer gets the same result for the speed of light. There are various ways of testing this, and they have always shown that this holds true.

Many aspects of modern physics also rely on ideas that are a logical extension of this, and the conclusions of these have also been tested.

So all of these support the idea that nothing can go faster than light.

As a result, it is unlikely that we will ever find anything that does go faster than light, and if we do it will have to be marginal to what we consider "every day reality" because otherwise it would already be reflected in our everyday experience.

Answer 4

It goes like this: The speed of light is the same for all observers, no matter what it equals 1/root(Epsilon naught Mu naught) (this was experimentally verified, quite accidentally, by Michelson and morely trying to prove the existence of the ether). Using this Einstein derived the special relativity equations. Many of these equations include a 1/root(1-v^2/c^2). This term blows up to infinity at c, so anything accelerating through c comes up against some very difficult barriers:
1)the entire universe ages infinitely during your journey
2)your momentum and kinetic energy go towards infinity and then jumps to negative infinity. Also the energy required to accelerate you goes towards infinity, so you simply stop accelerating.
3)you start going backwards, very suddenly, as length goes from 0 to negative in your direction of travel.
4)there are also some nasty electromagnetic effects that would have the effect of eliminating the force entirely (the electromagnetic force is carried by photons at the speed of light).

Answer 5

Because scintist assume the speed of light is constant, and never changes. Using E=mc2, you use engery to approch the speed of light, but for them to remain equal, ethier mass or the speed of light must increase. Well the speed of light wont increase, but mass does, so as you ezpend more energy, go gain more mass, instead of approching the speed of light. I hope this makes sense, and that it helps. But hey, I really dont trust the modern laws of phsyics, so mabye we can go the speed of light. As the y say, Absence of proff is NOT proof of absence. And, just to add on, scientists have found evidence that the speed of light has changed sense wqhen earth was first created. If i find the source I'll post it.

Answer 6

Interestingly, some scientists are beginning to agree with you. We say it because it was a necessary condition of Einstein's "Theory of Relativity" - the best attempt at explaining the way things work in the universe since Newton in the mid 1600's.

Most of Einstein's theories have proven to be true - or as "true" as anything can be in science - that is, they conform to our best ability to test them. They were grounded in this condition - that nothing could exceed the speed of light.

Nuclear science, for one, developed out of these theories, as did much of the science of astronomy and physics as we know them today.

Using Einstein's model, we have constructed our belief in the size and condition of the universe, and its beginnings, etc.

Now, some say the concept of time itself, and therefore velocity, are only human constructs, and that there is no suc thing as time. So "speed" would just be an illusion, anyway.

Answer 7

The speed of light in a vacuum is denoted by the letter c for constant or the Latin celeritas (speed). The speed of light through a transparent medium (that is, not in vacuum) is less than c; the ratio of c to this speed is called the refractive index of the medium.

In metric units, c is exactly 299,792,458 metres per second or 1,079,252,848.8 kilometres per hour. Converted to imperial units, it is approximately 186,282.397 miles per second, or 670,616,629.384 miles per hour. Note that this speed is a definition, not a measurement, since the fundamental SI unit of length, the metre, has been defined since 21 October 1983 in terms of the speed of light—one metre is the distance light travels in a vacuum in 1/299,792,458 of a second.

Answer 8

I remember reading an article about this.. i believe it went something like, once we start goin faster than speed of light well be breaking time/ space. and nature " supossedly" does and will not allow its not physically possible same goes for time travel or we wont be able to time travel beforer the point in time when the machine was invented

Answer 9

its about 700 mph! It is the fasting thing known to man or other. that is a FACT,

did u know that if u set a HUGE mirror that coveres half of earth, and u set up another mirror to another star in a different galaxy, it would take light millions of years to reach that other mirror. when it finally does, it reflecs an image of earth back to us, and do u know what happens?? Since it traveled so fast, and for so long, we would be able to see an image of Earth billions of years ago!! so the speed of light is like a time machine, cool huh!

Answer 10

Sorry, just over the past three years scientists have learned how to increase the velocity of photons greater than than light speed. They have also learned how to slow light to crawl.