Abstract: Some recent work in the quantum gravity
literature has considered what happens when the
amplitudes of a TQFT are summed over the bordisms
between fixed in-going and out-going boundaries.
We will comment on these constructions. The total
amplitude, that takes into account all in-going and
out-going boundaries can be presented in a curious
factorized form. This talk reports on work done with
Anindya Banerjee and is based on the paper on the
e-print arXiv   2201.00903.