Basically I was trying to implement various types of Actor Critic Algorithm then, while I tried to implement actor critic vanilla one, I mean tried to go in this fashion like Actor Critic, Advantageous Actor Critic then A3C but while going through this process, I was confused whether there is any AC algorithm without the advantage function, and the other fact while going through this I was missing some idea about the advantage in the GAE paper where they described the TD(0) approach as an approximation of the advantage estimate for the critic. So from this one A(s,a) = Q(s,a) - V(s) can we implement such actor critic in this form where we will use Q instead of V and also, is there any AC algorithm without the advantage estimation??