Electroweak corrections to the true muonium hyperfine splitting

In contrast to other atomic systems, in true muonium (mu(+)mu(-)) the leading-order Z boson corrections to the hyperfine splitting are shown to be experimentally accessible in the near future. This contribution (-109 MHz) constitutes a necessary contribution to a full O(ma(7)) calculation of the true muonium hyperfine splitting. This calculation would enable a number of possible solutions to the muon problem to be constrained. Additionally, we compute the general expression for a pseudovector coupling to particle-antiparticle bound states at leading order, including the annihilation channel.