← Open problems
MUB-10.9
Is the set of (mu + 2) MU bases from Thm. 6.11 unextendible?
In plain terms
Unextendibility of the Latin-square construction in square dimensions.
Our position — ours alone, not the authors'
Latin-square adjacency is our native vocabulary from the A6 work. Square dimensions means d=9,16,25... -- d=36 is the interesting one and is enormous.
Source
Daniel McNulty, Stefan Weigert, Mutually Unbiased Bases in Composite Dimensions -- A Review
Quantum 10, 2051 (2026) · §10.3
https://doi.org/10.22331/q-2026-04-01-2051
Licence:
CC-BY-4.0
— the problem statement is quoted here under that
licence, with attribution, and has not been modified