More than two thirds of the zeta zeros are simple and on the critical line
Determining unconditional lower bounds on the proportion of nontrivial zeros of the Riemann zeta function that are simple and lie on the critical line, and the proportion of distinct zeros. Previous unconditional records were 5/12 for simple on-line zeros and 0.6603 for distinct zeros.
Montgomery's 1973 conditional deduction is made unconditional by replacing the Riemann hypothesis with a rank-trace inequality applied to a finite compression of Weil's Hermitian form, using Sylvester's law of inertia to handle off-line zero pairs. The explicit formula and a test-function family are combined with linear-algebraic lemmas (inertia under pull-back, rank-trace inequality, Weyl bounds). Analytic inputs from Aryan and Baluyot-Goldston-Suriajaya-Turnage-Butterbaugh supply the Frobenius norm estimate. The main results are formally verified in Lean 4.
At least two thirds of nontrivial zeta zeros (with multiplicity) are simple and on the critical line, and at least five sixths are distinct. With the Montgomery-Taylor window the constants improve to 0.6725 and 0.8362. Results extend to primitive Dirichlet L-functions.
