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Of course, this is entirely an aesthetic opinion and not scientific on my part.
The article makes it seem like "the timeline corrects itself." What the scientific paper actually says (as best I can understand it) is that, if the universe is entirely deterministic, the conditions necessary for time travel can only occur when the time traveling wouldn't cause a paradox. As the authors note, this isn't super relevant to our universe because: - the conditions necessary for time travel probably don't…
It's actually even more general than that: under non-deterministic laws (such as the way most people currently understand quantum mechanics), if time travel is possible at all, the probability of it will only be nonzero for time travel scenarios that do not cause a paradox. (I don't think this is discussed in the paper referenced in the article, but it is discussed in some of the other papers that that paper references--IIRC the Novikov paper is one of them.)
One of the short stories in Ted Chiang’s recent book Exhalation deals with this theme. It’s a pretty interesting and entertaining read.
My naive understanding of time travelling back a single day would put me in a spot where earth will be a day later.
This suggests concepts like fate and the universe having a will and intent. It seems absurd. Wouldn’t a branching creating a new universe with its own timeline make more sense? Each unit of influence you exert as a time traveler branches a new universe in which you continue to exist and which has a completely new and separate timeline without paradoxes.
It's metaphysical philosophizing as far as I'm concerned -- interesting, but not terribly applicable, and heavily influenced by one's own beliefs and preexisting notions about the world.
One of the short stories in Ted Chiang’s recent book Exhalation deals with this theme. It’s a pretty interesting and entertaining read.
> Researchers ran the numbers and determined that even if you made a change in the past, the timeline would essentially self-correct, ensuring that whatever happened to send you back in time would still happen. I'm sure these researchers are pretty smart, but nothing in this article goes beyond the level of a grade-school debate. Maybe there's something enlightening in the paper. But if there was, you'd think it woul…
“Briefly stated, the Gell-Mann Amnesia effect is as follows. You open the newspaper to an article on some subject you know well. In Murray’s case, physics. In mine, show business. You read the article and see the journalist has absolutely no understanding of either the facts or the issues. Often, the article is so wrong it actually presents the story backward—reversing cause and effect. I call these the “wet streets cause rain” stories. Paper’s full of them.
In any case, you read with exasperation or amusement the multiple errors in a story, and then turn the page to national or international affairs, and read as if the rest of the newspaper was somehow more accurate about Palestine than the baloney you just read. You turn the page, and forget what you know.”
When you take this theory to it's logical conclusion, you end up with some strange outcomes. The strangest is the idea of going back and killing baby Hitler. When you attempt to do that, the universe, in it's self righting ways makes the assassination attempt not work. Since Hitler is a pretty big enemy for a lot of people, many people over time try to go back and kill Hitler. Hitler, on the other hand is just living…
https://www.imdb.com/title/tt9788516/
> Want to see Hitler die in a variety of comically fantastic ways? Now you can. Welcome to Multiversity!
Time travel violates the law of conservation of energy. By travelling back in time, you yourself are injecting more mass/energy into a system. So it's great as a science fiction trope, but if you're going to talk physics, that needs to be addressed.
I don’t have the details but I’m pretty sure passage of time is due to a tendency for entropy to increase, and that if I go back in time a second by, say, walking backwards, it is no more a violation of the cons of energy as if I walk forward.