Ciro Santilli
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Faster-than-light (FTL) | 🗖 nosplit | ↑ parent "Speed of light" | 105, 2, 105

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In special relativity, it is impossible to travel faster than light.
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One argument of why, is that if you could travel faster than light, then you could send a message to a point in Spacetime that is spacelike-separated from the present. But then since the target is spacelike separated, there exists a inertial frame of reference in which that event happens before the present. This has diagrams: http://www.physicsmatt.com/blog/2016/8/25/why-ftl-implies-time-travel TODO space diagram where FTL leads to timelike-separated event before the present.
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