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Cosmonaut Sergei Krikalev, the World's Most Prolific Time Traveler - Universe Today
Is time travel a fact or is it just science fiction? Thanks to time dilation and Einstein’s theory of relativity, we know that time travel can and actually does happen, albeit only in extremely tiny increments at the speeds and distances we can travel in space. If you add up the accumulated speed cosmonaut Sergei … Continue reading "Cosmonaut Sergei Krikalev, the World’s Most Prolific Time Traveler"