Nontrivial Riemann Zeros as Spectrum

Define \Upsilon(s) := \Gamma(s+1)\, (1-2^{1-s}) \, \zeta(s) , and denote by \mathcal{Z} := \left\{\gamma \in \mathbb{C} \;\middle|\; \Upsilon (\gamma)=0 \right\} its set of zeros, which includes both the periodic eta zeros, determined by (1-2^{1-s}) =0 with s \neq 1 , and the nontrivial zeta zeros \rho. We introduce a non-symmetric operator

\displaystyle \hat{\mathcal{R}} \colon \mathcal{D}(\hat{\mathcal{R}}) \subset L^2([0,\infty)) \to L^2([0,\infty)) \, ,

with spectrum

\displaystyle \sigma(\hat{\mathcal{R}}) = \left\{ i\left(1/2- \gamma \right) \;\middle|\; \gamma \in \mathcal{Z} \right\} \, .

Assuming that all nontrivial zeros of the Riemann zeta function are simple, we construct a positive semidefinite operator \hat{W} intertwining \hat{\mathcal{R}} and its adjoint on the spectral subspace associated with the nontrivial zeros, \hat{\mathcal{R}}^\dagger \hat{W} = \hat{W} \hat{\mathcal{R}} . The positivity of \hat{W} , which represents an operator-theoretic form of (Bombieri’s refinement of) Weil’s positivity criterion, enforces \Re(\rho)=1/2 for all \rho , in accordance with the Riemann Hypothesis. Furthermore, from the similarity between \hat{\mathcal{R}} and \hat{\mathcal{R}}^\dagger , we obtain a self-adjoint operator, whose spectrum coincides with the imaginary parts of the nontrivial zeta zeros.