From: Dan Asimov <dasimov@earthlink.net> To: math-fun <math-fun@mailman.xmission.com> Sent: Saturday, March 21, 2009 11:32:18 AM Subject: Re: [math-fun] If We Have Free Will, Then So Do Electrons What is the definition of a measurement at A being "influenced" by what happened at B ? --Dan Gene wrote: << [A] source S produces a pair of particles that are detected at A and B at space-like separation, so that A and B cannot influence each other (if you believe causality and relativity). It can happen that the measurements at A and B are correlated, e.g. if the z components of spins are measured, A has spin up if and only if B has spin up. These correlations become evident only when the recorded measurements are brought together and compared. The cause and effect relation responsible for such correlations is the common origin of the particles at S. There is no possible measurement at A that can be influenced by what happened at B.
This means that measurements made at space-time location A produce outcomes that depend on what measurements were (or will be) performed at location B, or depend on whether or not measurements occur at B. -- Gene