The small-$N$ series in the zero-dimensional $O(N)$ model: constructive expansions and transseries

Dario Benedetti, Razvan Gurau, Hannes Keppler +1

We consider the 0-dimensional quartic $O(N)$ vector model and present a complete study of the partition function $Z(g,N)$ and its logarithm, the free energy $W(g,N)$, seen as funct…