clopen.solutions

Open problems

980 registered problems.

OP-00036 Partially resolved
Vinzant's conjecture on 4M − 5 phase retrieval measurements
FA · frames · injectivity · phase retrieval · Randomstrasse101
OP-00037 Open
The Balan–Wang conjecture on the stability of real phase retrieval
FA · frames · phase retrieval · Randomstrasse101 · stability
OP-00039 Solution claimed
Zauner's conjecture
FA · equiangular tight frames · quantum information · Randomstrasse101 · SIC-POVM
OP-00044 Open
The Paley ETF restricted isometry conjecture
FA · compressed sensing · equiangular tight frames · Paley graph · Randomstrasse101 · restricted isometry property
OP-00075 Solution claimed
No seven mutually unbiased bases in ℂ⁶
CO · frames · mutually unbiased bases · quantum information · Randomstrasse101
OP-00199 Partially resolved
Complex equiangular tight frames with twice the dimension
FA · conference matrices · equiangular tight frames · line packings · OpenProblemsInNLA
OP-00348 Open
Hexagonal optimality for Gaussian time-frequency sampling
FA · AIM Open Applied Problems · frame bounds · Gabor frames · hexagonal lattices
OP-00689 Solution claimed
Finite-density time sampling of an infinite observation window
FA · AIM Open Applied Problems · Beurling density · dynamical sampling · frames