A. Connes, TRACE FORMULA IN NONCOMMUTATIVE GEOMETRY AND THE RIEMANN-HYPOTHESIS, Comptes rendus de l'Academie des sciences. Serie 1, Mathematique, 323(12), 1996, pp. 1231-1236
We reduce the Riemann hypothesis for L functions on a global field k t
o the validity (not rigorously justified) of a trace formula for the a
ction of the idele class group on the noncommutative space quotient of
the adeles of k by the multiplicative group of k.