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Graft wrote:This finding has implications for the design and interpretation of experiments, as it shows that the coincidence window loophole cannot be eliminated by a demonstration of independence of the detection times and settings.
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Recent experimental tests of local realism based on the Clauser-Horne/Eberhard inequality are considered and it is shown that in one case (Christensen et al.) the emission rate is appropriately limited to ensure valid counting, and the data confirms local realism; in a second case (Giustina et al.) the experiment fails to appropriately limit the emission rate, and the claimed violation can be accounted for locally.

Graft wrote:The recent Clauser-Horne (CH)-based Einstein-Podolsky-Rosen-Bohm (EPRB) experiment performed by Christensen et al. is analyzed. The data analysis performed by Christensen et al. is shown to rely upon postselection (data discarding) that produces an artifactual violation of the CH inequality. A corrected analysis that properly includes all of the experimental data is developed, showing that the Christensen et al. experiment confirms locality and disconfirms the quantum joint prediction.

Code: Select all

A = +sign(g(a,e,s))  # Alice's measurement results A(a, e, s) = +/-1  # Here g(u,v,s) is a metric on S^3, reducing to the usual g on R^3
B = -sign(g(b,e,s))  # Bob's measurement results B(b, e, s) = -/+1    # A(a, L) = +/-1 and B(b, L) = +/-1 are exactly as defined by Bell
     
Cuu = length((A*B)[A > 0 & B > 0])   # Coincidence count of (+,+) events
Cdd = length((A*B)[A < 0 & B < 0])   # Coincidence count of (-,-) events
Cud = length((A*B)[A > 0 & B < 0])   # Coincidence count of (+,-) events
Cdu = length((A*B)[A < 0 & B > 0])   # Coincidence count of (-,+) events
       
corrs[i,j] = (Cuu + Cdd - Cud - Cdu) / (Cuu + Cdd + Cud + Cdu) # = -a.b

# There are no "0 outcomes" within S^3: Cou = Cod = Cuo = Cdo = Coo = 0
CoB = length(A[g(a,e,s) & A == 0])   # Number of A = 0 events within S^3 (regardless of B events) = 0
CAo = length(B[g(b,e,s) & B == 0])   # Number of B = 0 events within S^3 (regardless of A events) = 0