Quantum Chaos

Some passages in Poul Anderson's Time Patrol series account for causality violation without reference to a mutable timeline or to a temporal succession of altered timelines. (These are two ways of saying the same thing.)

Everard, using "you" as a collective pronoun, thinks that, if you change the past, thus preventing your own birth:

"You, pastward of the change, would still be there; but returning futureward, you'd find a totally different world...You'd exist, but as an effect without a cause, thrown up into existence by that anarchy which is at its foundation." (Time Patrol, p. 672)

If you have begun to exist with false memories as a quantum fluctuation, then you have not traveled from the future of a previous timeline and you would not "return" futureward but would travel in that direction for the first time.

Wanda asks Everard where she would have come from if she prevented her own birth. He replies:

"'From nowhere. From nothing. Cause-and-effect doesn't apply. It's sort of like quantum mechanics, scaled up from the subatomic to the human level.'" (The Shield Of Time, p. 30)

Again, this clearly states that Wanda's birth did not occur in a previous timeline (or in a previous state of the mutable timeline) but has never occurred anywhere anytime. This is counter-intuitive but not logically impossible. However, Time Patrolmen do become logically incoherent when they add that it is possible that there own present existence and experience does not occur.