Posted August 25, 2020
there was once a gamer, in his or her own right, who could play games at the speed of light. they played a game one day, in a RELATIVE way, and finished the game the previous night!
* Going near the speed of light will still cause you to go forward in time; you can actually, in an arbitrarily small amount of time (from your perspective) you can travel arbitrary distances and go forward arbitrary amounts of time. (This is the rule that makes it possible for your grandchildren to be older than you.) Note that it still takes some time from your perspective.
* Going at the speed of light will allow you to go arbitrary distances in 0 time from your perspective. In other words, from your perspective, travel at the speed of light is instant. (It isn't instant from an observer's perspective, however.)
* Traveling *faster* than the speed of light is required to actually travel backwards in time. With that said, physicists generally believe that nothing goes faster than light (though there are some theories that allow such particles, which are called "tachyons", that do go faster than light, but bight be difficult or impossible for us tardons to interact with.) In any case, doing the special relativity calculations with speeds faster than light will result in things like square roots of negative numbers; in other words, you may have particles with imaginary mass!
(Special relativity is relatively easy to wrap your head around if you understand algebra; general relativity, on the other hand, is far more complex and less accessible, but I believe is needed for GPS to work properly.)
(For those who prefer more scientifically rigorous terminology, replace "perspective" with "reference frame".)
By the way, a great quote from Google on one particular day: "Stephen Hawking died tomorrow at age 76".
