The more I think about it, the producers have dismissed time travel.
They have not dismissed taking the concepts of Einstein's Theory of
Relativity to new conclusions. Forgive me if my extrapolation feels
half baked, and if you really knowthis better than I do, please share
your thoughts.
Relativity of simultaneity basically says: "It is impossible to say in
an absolute sense whether two events occur at the same time if those
events are separated in space." (Wikipedia)
So you have on the island and off. Desmond finds himself observing at
two time simultaneously. To him, it's the same time, because he keeps
switching consciousness back and forth.
"Einstein's special theory demonstrates that there are occasions when
there is no 'correct' answer, where no observer has a privileged
status, and all the observers can claim to be 'correct' even if their
ordering of events disagree with each other."
That is why Desmond needs a constant-- Penny. It is through her that
he can establish a frame of reference that will keep him from going
insane from not having any correct answer to make sense of.
What really would be a mind**** is if the Lost flashbacks are not
really flashbacks, but each character experiencing this disorientation.


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