“…Usually, to come back to the matrix gravity, one needs a deformation theory [25,26,38,46]. But, the recent studies [26,28,30,68] all together show that one can start with Witten's topological gravity and come back to the matrix gravity without a deformation theory, again at least in the higher genera. More precisely, we first go to the special cubic Hodge partition function by a space/time duality [18,67,68] (see also [2,3]) (in [68] this is revealed by the Hodge-BGW correspondence), and then go to the so-called modified even GUE partition function by the Hodge-GUE correspondence [26,28], and finally back to the even GUE partition function via a product formula [30], again at least to the higher genera in jets.…”