There's actually a much older idea, called the Novikov Principle, which is more directly related to temporal paradoxes: basically, it states that for any "closed timelike curve" - physics for a timeline which loops back on itself - there is are an infinite number of possible timelines in which the act of traveling back causes a result in which the future has not been changed.
The example used in the original work: you cannot hit a billiard ball through a time portal such that it will knock itself off course and miss the time portal, because if you try, a billiard ball will come through the time portal and mess up your aim just enough that instead of knocking the billiard ball away from the time portal, it will just mess up your aim a little bit.
...they have done the math. They have proven that, in a universe where time travel happens via closed timelike curves, not only would this work, there is no possible set of initial conditions for which it would not work, and you can use the same "principle of least action" to determine the most likely angle at which the ball will emerge from the time portal.
...and then somebody went and said, "Wait, if you can predict the angle at which it emerges, that basically means you can *send yourself information from the future*, and someone - not an SF writer, a real scientist - has actually written a hypothetical computer program that performs mathematical calculations by setting up a situation where a paradox will happen if the correct answer does not appear from the future.
Physics is *deeply awesome*.
And yet, 90% of the SF stories I've encountered that use something like that in time travel physics either refuse to explain or develop it, or end up going somewhere ludicrously anthropomorphic with it, attributing intention, when the awesome part is that you don't *need* anything more elaborate than apparently silly coincidences happening, because it seems that the universe believes in the law of narrative causality.
And magic has been blamed on probability manipulation at least as far back as the Scarlet Witch's debut in X-Men in 1964 (and probably earlier!)
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The example used in the original work: you cannot hit a billiard ball through a time portal such that it will knock itself off course and miss the time portal, because if you try, a billiard ball will come through the time portal and mess up your aim just enough that instead of knocking the billiard ball away from the time portal, it will just mess up your aim a little bit.
...they have done the math. They have proven that, in a universe where time travel happens via closed timelike curves, not only would this work, there is no possible set of initial conditions for which it would not work, and you can use the same "principle of least action" to determine the most likely angle at which the ball will emerge from the time portal.
...and then somebody went and said, "Wait, if you can predict the angle at which it emerges, that basically means you can *send yourself information from the future*, and someone - not an SF writer, a real scientist - has actually written a hypothetical computer program that performs mathematical calculations by setting up a situation where a paradox will happen if the correct answer does not appear from the future.
Physics is *deeply awesome*.
And yet, 90% of the SF stories I've encountered that use something like that in time travel physics either refuse to explain or develop it, or end up going somewhere ludicrously anthropomorphic with it, attributing intention, when the awesome part is that you don't *need* anything more elaborate than apparently silly coincidences happening, because it seems that the universe believes in the law of narrative causality.
And magic has been blamed on probability manipulation at least as far back as the Scarlet Witch's debut in X-Men in 1964 (and probably earlier!)