But when attendees gathered outside for a raucous countdown at 10 p.m. Eastern Standard Time, nothing appeared on the makeshift landing pad at the coordinates Dorai set for the time travelers….
It’s actually a blessing that no one from the future showed up on Saturday night, said David Batchelor, the NASA physicist who wrote “The Science of Star Trek.”
Speaking on his own behalf and not for NASA in a phone interview, Batchelor noted the same potential risks mentioned by speakers at the convention, such as the displacement of matter in a finite universe caused by the introduction of someone from another time. He also touched on the paradoxes arising from such acts as going back in time and killing one’s own ancestors.
“We should breathe a sigh of relief,” said Batchelor, who considered his decision not to go to the convention a safe bet. “It means we were protected from the chaos that would result if someone came back and changed something.”
The thought that struck me as I read this was, if time travelers came from the future to attend the convention “after the fact”—wouldn’t our memories change to match the altered timeline? In other words, we wouldn’t know that no one from the future appeared, because they in fact did and time was changed.
Alternatively, travelers from the future did attend the convention, only that spun off into an alternate timeline and our own timeline is undisturbed.