[extropy-chat] Re: Damien grants psi evidence

[scerir]

From: "Dirk Bruere" 

> It begins with the Delayed Choice expt and a Cramer 
> style interpretation of a 'backward in time signal' 
> upon measurement that sets a 'real' unique path 
> for the photon retrospecively. [...]. The question 
> that has nagged me is: Is that loop local limited 
> to the photon/apparatus or does it essentially 're-run' 
> the universe over that duration?

It is a 'transaction', limited to the sources of advanced
and retarded fields. The rest of the universe remains
unchanged, independent. That said there is a real problem
of definition of time(s).

But the 'delayed choice' strategy is, perhaps, interesting.

                ESP domain

Dirk                |               Walter
                                
Dirk figuring (or pre-figuring, or post-figuring) 
Walter's cards. Of course we must compare, in some
place and time, Walter's outcomes and Dirk's results.


                      Quantum 

Dirk/Two-slit Int. <--p1-- s ---p2--> Two-slit Int./Walter

The source s emits entangled photons. p1 to Dirk's two-slit 
interferometer. p2 to Walter's two-slit interferometer.
Dirk and Walter get similar interference patterns. No
information if we compare these interference patterns.
They are similarly random. 

                Quantum Delayed Choice

Dirk/Two-sl.I.<---p1-- s --p2--------------> Two-sl.I./Walter

The source s emits two entangled photons. p1 to Dirk's 
Two-slit interferometer. p2 to Walter's Two-slit interferometer.
Walter (who is far away from the source s of entangled photons) 
has time to choose if (or not) to put a lens inside his Two-slit
interferometer. (Dirk _already_ got his spot on the screen,
that is p1 already reached Dirk's screen in some place, and
was registered). If Walter inserts a lens inside his 
interferometer, his interferometer becomes a Heisenberg 
microscope, imaging the two slits, thus Walter now knows 
the 'which way' of his photon p2. But if Walter knows 
the 'which way' of his photon, does he also change 
- given the strict correlation between momenta of entangled 
photons - Dirk's interference pattern (just one spot actually)? 
No, because Dirk's interference pattern (one spot) was registered 
_already_. No information, again, reaches Dirk, whatever Walter 
may choose, i.e. to insert, or not to insert, at a later time, 
a lens inside his interferometer? No possible 'back in time' 
information to Dirk? No possible 'back in time' information 
to Dirk. But if we compare Dirk's interference pattern
(actually just one spot on a screen) and the 'later' Walter's
choice (to insert, or not to insert, a lens inside his
interferometer, as to trasform it in a Heisenberg microscope)
we find that both the registered and experimental facts are
consistent. In the sense that the registered position of Dirk's
spot is always consistent with the 'later' choice by Walter.
And this is, of course, a big surprise.