Radiative corrections to the decay rate of orthopositronium

Abstract

The $e^8$ corrections to the decay rate of orthopositronium are calculated. For this calculation, as for bound-state problems in general, special attention must be given to infrared and Coulomb terms. The final result of this calculation is that the $e^8$ corrections yield a decrease in the lifetime of approximately 0.4% which represents a discrepancy of 2½ standard deviations with the current experimental value.