Depends on the notation. Sometimes Q* is used to denote optimality, for example here : https://www.cs.toronto.edu/~jlucas/teaching/csc411/lectures/lec21_22_hand

Depends on the notation. Sometimes Q* is used to denote optimality, for example here : https://www.cs.toronto.edu/~jlucas/teaching/csc411/lectures/lec21_22_handout.pdf https://www.cs.toronto.edu/~jlucas/teaching/csc411/lectures/... , page 31