== Virtual Pin Holes == 

 In case it is not obvious how Afshar's results can still be obtained if, everything else being equal, we were permitted to respecify the upstream constraints, the following is an example. 

 1. Remove the pinhole construction. 
 2. Leave everything else as is, including Afshar's results. 
 3. Place pin size obstacles at those locations formerly occupied by the pinholes. 
 4. Place adjacent to such (at least a few pinhole widths away) a hologram of the pinholes. 
 5. Project laser light through the apparatus. 

 If properly constructed the downstream data will be the same as Afshar's.  

 Yet a "which way" inference (from the downstream data) would be incorrect since there are, in fact, obstacles at the inferred upstream locations. 

 Now of course we're talking about real particles, ie. measurements made in the shadow of the pinsize obstacles. Afshar's particles are measured ex situ.  

 Well in this experiment, we can also measure such particles, ie. ex situ. And we'd find they'd be doing exactly the same thing here as they do in Afshar's experiment: 

 ie. indicating "which way" they went, despite actual obstacles to such! 

 Should we conclude our pin size obstacles are not really there?  

 I guess we could ... 

 Carl Looper 
 19 January 2006