Lets pretend I am in my space ship going in one direction at 0.9c. My brother is in his space ship going the opposite direction also at 0.9c. Oh and there is a big clock on the side of our ships. When we cross paths, to me it looks as if i'm not moving and my brother is moving at 1.8c. I am aware that the formula for time dilation is t0 = t√1-[itex]\frac{v^{2}}{c^{2}}[/itex] and that velocities don't simply add together, the formula for that is V[itex]_{3}[/itex] = [itex]\frac{v_{1}+v_{2}}{1+\frac{v_{1}v_{2}}{c^{2}}}[/itex]. Using that formula for velocity the speed would be about 0.9945c. this only makes sense to me if the two velocities are in the same direction. So lets just forget the formula for velocity. I see my brother moving faster than light. Lets also pretend I have some kind of telescope that can perceive vision instantaneously. Using the time dilation formula, I would be left with t√-0.8 I know you can't really find the square root of a negative number, so what would I see? Would I see his clock run slow but forward like normal, not move at all, or backwards?(adsbygoogle = window.adsbygoogle || []).push({});

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# Does time go backwards if object is going faster than light?

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