Suppose that starting this year (2019), I and all people who are important to me will do the following: We will live for 20 years on a delightful planet, and then travel through spacetime both 20 years back and to another delightful planet, and repeat ad infinitum.
Then, we won’t exist after the year 2039. But notice that this needn’t matter to us! Indeed, we are no worse off than if we skipped the time travel, and lived forever, moving between delightful planets every 20 years.
This is yet another thought experiment showing that what is important to us is internal and not external time.
Not to be a nuisance, but doesn't this actually just illustrate the absurdity of time travel? It makes no sense that I am both on this planet and that one at the same time, or that I am both older and younger at the same time. It's not even false; it is meaningless.
ReplyDeleteAt best, we'd need a "time machine" (I know you didn't mention a machine; but it makes my point clearer) that is instead actually a "world-resetter", such that the state of affairs (including the acknowledged date) are back to where they were 20 years ago. It is still 20 years later, but the states of affairs have been perfectly reset.