DCQ Pencil Top


[Contextual Image]

Instructions: Name That Place

_ _ _ _ a _ _ _


This puzzle requires understanding what is happening within a very bizarre quantum mechanical experiment.

  • 3
    $\begingroup$ Although I am not able to figure out the exact mechanism, <spoiler>this will help others to find the starting point. $\endgroup$
    – ACB
    Commented Nov 18, 2022 at 13:09
  • $\begingroup$ If the electron goes through slot 1 then the logic is the electron did not go through slot 2 so then the later measurement of the property of did the electron pass the slot nullifies the property did. $\endgroup$
    – Willtech
    Commented Dec 20, 2022 at 8:08

1 Answer 1



Solution Part 1:

The experiment shown in the diagram is the Delayed Choice Quantum Eraser Double Slit Experiment.

This experiment breaks time itself by entangling a particle (photon) through a crystal after a double slit. The entangled particle on the North Path hits Detector 0 (not labeled) first, while the South Path adds post-processing. Because of the bizzare nature of entanglement, the two correspond instantaneously without regard to distance, or in this experiment, time.

The first set of half-mirrors reflect half of the particles to either Detector 1 or Detector 2. These first 2 detectors on the South Path retain information about which slit the particle passed through. So the resulting pattern we see on the North Path is particle-like (two bands). But if the particle passes through the first half mirrors to the dark black full mirrors, it reflects through a scrambling filter on the way to Detector 3. At Detector 3 the which-path information is destroyed, so the North Path retroactively registers wave-like patterns.

Based on this information, we can conclude that the measurement we are seeing on the North Path corresponds to Detector 3, because the which-path information was destroyed.

Solution Part 2

If we destroy every 3rd letter in the string of letters SILNZEANGIA ESEPCZUANGIA, we get


Solution Part 3

Sine (Sin) and Secant (Sec) are trigonometric operations. Secant is the inverse of Cosine (Cos). Substituting, we get Sin x Sec = Sin / Cos = Tangent (Tan). This leads us to the answer, Tanz[a]nia.


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.