matter of speed?

Question

i had read that we can't acquire speed greater then c it is right from the formula m0/(1-(v2-c2)) but i had also read that if we increase our speed greater then c then we can reach past how is it possible.

Answer 1

Brian is correct: an object that has any mass cannot reach the speed of light because it would take an infinite amount of energy. But if we *could* go faster, we would be able to see things from the past.

Some people say that we can visit the past and interact with it as our faster-than-light travel would take us outside of the future light cone (see Stephen Hawking's book "A Brief History of Time" for an explanation of light cones). However, this would probably take us to an alternate universe, not the one from which we came. This conjecture has not been proved, of course.

The bottom line is that we cannot go faster than c.

Answer 2

The constant "c" refers to the speed of light in a vacuum. Our current best speed is still only a small fraction of this speed. Time travel is the stuff of science fiction, and if we could exceed the speed of light we could see into the past but not "reach" the past. So for the sake of argument you hop into a faster than light craft and jaunt to Pluto. if you look back at the earth, with an impossibly strong telescope, you would actually see yourself in the past but couldn't travel to the past.

It is just like looking at the stars, because the light takes so long to reach the earth, the "images" you see are already very old, in some cases the stars you are currently seeing could have died millions of years ago and we just haven't seen that light yet.

Answer 3

time varies with speed, the faster some one or thing goes the more time for that object slows, therefore at the speed of light time would stand still so if you went faster time would begin to go backwards