The term m-1 j=1 sin 2 θj 2 is replaced by 1 when m = 1. Using the definition of Θ n (Eq. 74) one can further express it into Eq. 77. Alternatively, we can use the kernel expressed in Eq. 27 to evaluate |n m| s = Tr e [|n m| ŵs (Ω)] = r s Ω|n m|Ω , then using the definition of n|Ω (Eq. 18) to get