# Holography with wave functionals rather than partition functions

Roughly speaking Gubser-Klebanov-Polyakov Witten's (GKPW) prescription in the context of holography tells us partition function of CFT is "equal" to that of the gravity theory in one higher dimension $$Z_{CFT_d} \equiv Z_{AdS_{d+1}}$$

with particular boundary conditions. The boundary values of the field propagating in the bulk are actually the sources to certain CFT operators. Then taking partial derivative of $Z$ with respect to those sources and fixing them to zero at the end we obtain the n-point correlators.

But the full partition function in itself contains a lot of information. For example in condensed matter systems usually only the knowledge of the ground state is useful enough. Is there some GKPW like prescription at the level of wave functional?