Key points are not available for this paper at this time.
We calculate the three-loop matching coefficient CHH, required for a consistent description of Higgs boson pair production in gluon fusion through next-to-next-to-leading order QCD in the heavy top quark approximation. We also compute the gg→HH amplitude in mt→∞ approximation in the full theory and show its consistency with an earlier computation in heavy-top effective theory.
Grigo et al. (Mon,) studied this question.