At the speed of light time stops. Really?

Answer 1

It has to do with the nature of space and time or more accurately, the nature of spacetime. It turns out that both space and time are relative and how much space and time you experience depends on your frame of reference.

For example, imagine you were to travel in a spaceship at 99% the speed of light to a distant star that was a 100 trillion kilometers away .

Those left at home would see the distance you traveled to be 100 trillion kilometers and would consider the time it took you to be about 10 years.

However, you in the spaceship would only measure the distance to the star to be 14 trillion kilometers instead of 100 trillion kilometers and you would think it only took you 1.4 years to travel there instead of 10 years.

If you traveled even faster at 99.99% the speed of light you would measure the distance to be 1.4 trillion kilometers instead of 14 and you would think it only took you 0.14 years instead of 1.4.

If you traveled even faster at 99.9999% the speed of light you would measure the distance to be 0.14 trillion kilometers instead of 1.4 and you would think it only took you 0.014 years instead of 0.14, and so on.

The closer to the speed of light you travel the shorter the distance becomes for you and the less time it takes you.

As you can see "space and time becomes less and less" for you in the spaceship relative to us here on the earth.

What it comes down to is that different people see space and time differently, depending on the "frame of reference" from which they are looking at things.

Note however that it would be impossible for you to travel at exactly the speed of light because it would theoretically take you an infinite amount of energy to get up to that speed. Light can do it because it has no "rest mass".

For light when it travels from one point to another at the speed of light, from its point of view, it experiences no passage of time and there is no distance between the two points.

Answer 2

More accurately, according to the theory of relativity, time dilation approaches infinity as an observer's velocity approaches the speed of light. The mathematics breaks down atthe speed of light ('c') - for at the exact speed of light, mass and time dilation become infinite. That is why we say nothing with a rest mass can reach the speed of light.

Answer 3

At the speed of light, time does not stop, but instead appears to slow down as observed by an outside observer. This is a consequence of Einstein's theory of relativity, where time dilation occurs as objects approach the speed of light.