A New Loophole in Recent Bell Test Experiments

Understand

Recent experiments have reached detection efficiencies sufficient to close the detection loophole with photons.

• Both experiments ran multiple successive trials in fixed measurement configurations, rather than randomly re-setting the measurement configurations before each measurement trial.
• This opens a new potential loophole for a local hidden variable theory.
• The loophole invalidates one proposed method of statistical analysis of the experimental results, as demonstrated in this note.