OP-00038 Partially resolved A degree-4 Sum-of-Squares proof that ℂ⁶ has no seven mutually unbiased bases OC · mutually unbiased bases · Randomstrasse101 · semidefinite programming · Sum-of-Squares
OP-00075 Solution claimed No seven mutually unbiased bases in ℂ⁶ CO · frames · mutually unbiased bases · quantum information · Randomstrasse101
OP-00699 Solution claimed The maximum number of mutually unbiased bases in dimension six CO · AIM Open Applied Problems · complex Hadamard matrices · mutually unbiased bases