[extropy-chat] Is Many Worlds testable?

[scerir]

Russell Wallace
> I was thinking along the lines of: put a detector 
> at each slit to check which one the particle went through, 
> but instead of displaying the result on a screen, 
> record it to flash memory without looking at it. 
> Interference pattern stays gone.

The solution Zurek and Wootters gave to this problem
is simple and radical.

Why check the 'which path' the particle went
through _before_ the screen (between the 
two-slit and the screen)?

Let us check the 'which path' _behind_ the screen,
after the screen has registered (in a non
reversible way) every single spot, and the entire 
interferential pattern.

How? Perhaps the nanotech would help here. The trick
is to make a special screen, made of little tubes.
Each tube may register both the spot (the position
of the particle on the screen) and the direction
of the particle, from the slit a or the slit b. 
 
If the geometrical trick works, knowing both the 
position of the spot and the direction of the particle
from the slit, it would be very interesting to see if
the pattern is still interferential or not.

(If the pattern is not interferential it means that
the tubular screen has an action, backwards in time,
on the particles, while they are passing the slits).