Quantum M2→2Λ/3 discontinuity for massive gravity with a Λ term

In a previous paper we showed that the absence of the van Dam–Veltman–Zakharov discontinuity as M2→0 for massive spin 2 with a Λ term is an artifact of the tree approximation, and that the discontinuity reappears at one loop, as a result of going from five degrees of freedom to two. In this Letter we show that a similar classical continuity but quantum discontinuity arises in the “partially massless” limit M2→2Λ/3, as a result of going from five degrees of freedom to four.