attaining the speed of light?

Question

I always heard this was an impossible feat but in a previous question about acceleration in a vacuum due to gravity I was rewarded with this grand answer

"There is a speed limit to everything, though, and that’s the speed of light; nothing goes faster, not even things that have been falling in a gravitational field for a long time."

so if i drop a teddy bear down a vaccum tube of infinate length it will reach the speed of light?

Answer 1

The theory of relativity shows that it cannot. Let's just say that you keep applying a force to something, rather than that you have an infinite vacuum tube (since there needs to be continued acceleration in that vacuum tube).

The trouble is that, since E=mc^2, m=E/c^2, so the object acquires a higher mass - the mass of its energy. As it becomes heavier, it becomes harder to accelerate, so it only approaches the speed of light, even as you add energy to it. The mathematics is, in reality a little more complicated than this, but this really is what's going on - as an object gains energy, it becomes more massive, and harder to speed up. E=1/2 mv^2 for kinetic energy works only for speeds much less than the speed of light.

Answer 2

Well, the idea is that under current theory, "c" is the fastest speed and that anything with any mass simply can't reach that speed. That's because as the speed of an object increases, so does its mass. To go that last unit of acceleration from "c-1" to "c" would mean that the mass of the object would reach infinity, thus requiring an infinite amount of energy (E) so that the speed of the mass reaches "c." So, it renders E=mc2 nonsensical, because E would be infinity and m would be infinity and so it would be infinty equals infinity times the speed of light squared.

What I think must be understood is that relativity is only a partial theory of the universe. It is not yet harmonized with quantum mechanics and quantum gravity, and physicists are still searching for that elusive "theory of everything."

In short - relativity is wrong, to one degree or another.

Answer 3

first you or ANYBODY tell me why they think nothing can go faster than light, HOW DID ANYBODY "CONCLUDED" THAT NOTHING CAN GO FASTER THAN LIGHT?!?!?


a bit earlier today I ran into a question about light speed. it wasn't really a question, but someone, I don't remember who, said he knows how to travel faster than light. although I told him some problems which were too big for him to solve them by himself, I was hit by a great creativity and theoretically very possible idea. the guy posted this:

Tell me if this would work or not.

You take a really long pole, I mean really really really long. And swing it with one end connected to a point in a big circle in space. The end of the pole moves faster then the part of the pole closer to the pivoting point since it has to cover more distance right? If you do the math wouldn't the end of the pole reach the speed of light?

the guy's nick on yahoo is sirgarr02


by that story I stand behind the fact that the light speed isn't inapproachable.

this is only the beginning. the ideas of use of the mechanisms for traveling faster than light are not so close to human race, but will be some day!

Answer 4

Visible Light exists in a frequency/vibration and there are modes that exist beyond that, such as Gamma or X ray frequencies which are "faster". Time and distance are relative quantities so you need limits in order to measure speed. Aside from working in a vacuum and around gravity, I think phases of matter determine the greater part of light speed travel.

Answer 5

Wrong
Even if U acclerate something at the speed of light
it can reach a speed greater than that
but according to the einstein's relativity
nothing can go beyond the speed of light
but the truth is that U cant just measure it

Answer 6

Not sure.toreach great speeds you must have an acceleration due to gravity and so you can not use an infinte tube since the gravity lowers with distance.
You must also avois friction forces
And do not forget, the mass increases with speed

Answer 7

First of all consider that the speed of light is relative to our dimension only and since there are unlimited dimensions (String Theory under construction here....) and distance becomes a flexible dimension, the cosmic speed limit can be transversed with impunity....

Answer 8

Using earth's gravity as an example, the moon which is 240.000 miles from the centre of the earth feels only 1/3600 times the pull of gravity, it falls just 1/20 inch in one second.