Recently four mathematicians claimed to have proven the invariant subspace problem, which is the problem that states > Does every bounded operator on a separable Hilbert space have a non-trivial invariant subspace? They claimed to have proven the existence of a non-zero weak limit that is orthogonal to the entire space and that gave rise to a contradiction. For those interested this is the link to the paper: https://www.mdpi.com/2075-1680/13/9/598 So my question is, since the paper was published in a journal does that mean the problem is closed?