But any knowledge you gain will change your behavior in the future, it’s unavoidable, and those changes will compound causing the divergence to grow over time.
The only way to avoid “erasing” the timeline is to propose a time travel mechanism through which the timeline never changes despite passing information to the past, and that’d be basically what I suggested, taken to a bit more extreme of a conclusion - that because any other possibility would cause a paradox, your future self must have already made the optimal choice and will be satisfied telling your past self what they already heard in the past themselves.
Well, either that, or you just continue existing in a different timeline, with no benefit from helping your past self.
But any knowledge you gain will change your behavior in the future, it’s unavoidable, and those changes will compound causing the divergence to grow over time.
The only way to avoid “erasing” the timeline is to propose a time travel mechanism through which the timeline never changes despite passing information to the past, and that’d be basically what I suggested, taken to a bit more extreme of a conclusion - that because any other possibility would cause a paradox, your future self must have already made the optimal choice and will be satisfied telling your past self what they already heard in the past themselves.
Well, either that, or you just continue existing in a different timeline, with no benefit from helping your past self.