Discussion about the orthopositronium decay rate and analysis of some   $O(\alpha^2)$ contributions
  I consider the problem of the evaluation of the orthopositronium decay rate, including second order radiative corrections. I present a brief theoretical discussion of this problem and a review of the results available in literature, and, then, I analyze some $O(\alpha^2)$ annihilation-type contributions, recently computed. 
V. Antonelli