Special Issue Entropy in Quantum Gravity and Quantum Cosmology

Four years ago, I proposed an issue entitled “Entropy in Quantum Gravity,” to give a partial picture of the state of the art. In this renewed issue, I would like to enlarge the discussion to include also Quantum Cosmology. Of course, Quantum Gravity and Quantum Cosmology are intimately connected, and it is also clear that the subject of studying Entropy in Quantum Gravity and Quantum Cosmology is far from being exhausted. This Special Issue focuses on different contributions and approaches by some of the leading researchers in this field.