Submitted on 2020-01-03
In this note, I analyze the code and the data generated by M. Fodje's (2013) simulation programs "epr-simple" and "epr-clocked". They are written in Python were published on Github only, initially without any documentation at all of how they worked. Inspection of the code showed that they make use of the detection loophole and the coincidence loophole respectively. I evaluate them with appropriate modified Bell-CHSH type inequalities: the Larsson detection-loophole adjusted CHSH, and the Larsson-Gill coincidence-loophole adjusted CHSH (NB: its correctness is conjecture, we do not have proof). The experimental efficiencies turn out to be approximately eta = 81% (close to optimal) and gamma = 55% (far from optimal). The observed values of CHSH are, as they must be, within the appropriately adjusted bounds. Fodjes' detection-loophole model turns out to be very, very close to Pearle's famous 1970 model, so the efficiency is very close to optimal. The model has the same defect as Pearle's: the joint detection rates exhibit signaling. The coincidence-loophole model is actually an elegant modification of the detection-loophole model. Because of this, however, it cannot lead to optimal efficiency. Later versions of the programs included an explanation of how they worked, including formulas, though still no reference whatever to the literature on the two loopholes which Fodje exploits, not even to the concept of an experimental (i.e., in principle, avoidable) loophole. The documentation available now does make a lot of the "reverse engineering" in this paper superfluous. I plan to rewrite it as a very, very short note. I will also use the few jewels in the work in a more ambitious paper, still to be written, about the results of the bigger research project of which these experiments were a small part.
The two authors listed by Researchers.one are both myself, in my two capacities as emeritus professor and as independent consultant. Actually I was just attempting to add my middle name "David" or middle initial "D." to my name on my own profile. But only succeeded in cloning myself.