Originally posted by sonhouse
I think the deal now is not the observer but the measurement of a phenomena that interacts with the target. Don't forget, the idea that the quantum phenomena associated with an observer effects is only true now because there is at least one planet in the universe with observers. Right when stars were first forming and before that, there was an extremely hig ...[text shortened]... ped up, the universe didn't just snap to attention and change its ways just in response to us.
Yes, I get that the universe isn't that which changed -- it is we who change. The story concerned the usual physics gadget gone wrong -- it explodes and our hero is put into what appears in our continuum to be a 24-day coma. but he awakes and eventually tells us what, subjectively, occurred from his point of view. His consciousness was transported or transposed with an alternative history in which WW II never happened. So, our hero lived a different life and most things while very similar were also quite noticeably different -- friends who were wounded in the war he meets are not missing the fingers they lost, etc. And, of course, he meets the perfect woman, to whom he is married in this alternative life. When he wakes from the coma back in the main thread of his life, he is distraught and sets out to find that woman, whom he insists must exist also in his own continuum.
The story is well done, but dated -- not too many folks today would find it styled for their taste. But the SF aspect of the story prompted my question -- the author, John Wyndham, who died in 1969, posited that among all the infinite quantum universes that diverge from a single "atom of time," enough of one continuum would also exist in most if not all others, even if quite clearly altered.
So in this story, I doubt there is a "target." He wasn't suggesting Heisenberg's idea that the observer changes the universe, he was saying the universe one observes may be different depending on where you happen to be in relation to it in four-dimensional space-time. At least that's what I think he meant.