---
title: "quantum pigeonhole principle"
type: "entity"
entity_kind: "concept"
status: "hub"
canonical_name: "quantum pigeonhole principle"
aliases: []
first_seen: "2026-10-23T00:00:00.000Z"
writer_model: "claude-sonnet-5"
connects_to: ["weak value","pre- and post-selection","Yakir Aharonov","Sandu Popescu","quantum foundations"]
seek_code_commit: "d40ee39"
---


A 2016 result (Aharonov, Colombo, Popescu, Sabadini, Struppa & Tollaksen, *PNAS* 113:532) showing that three or more non-entangled, identically pre- and post-selected particles can — via [[entity-weak-value|weak-value]] reasoning — occupy fewer "boxes" than particles, with no two ever found together, violating the classical pigeonhole principle without relying on entanglement. In the vault it is [[entity-yakir-aharonov|Yakir Aharonov]]'s and [[entity-sandu-popescu|Sandu Popescu]]'s joint demonstration that pre/post-selection alone, not correlation between particles, can produce counting-defying results.

## References
- [[claim-aharonov-2016-quantum-pigeonhole-three-particles-two-boxes-weak-value]]
- [[claim-quantum-pigeonhole-paper-won-2016-cozzarelli-prize]]