Submissions from Pasquale Liguori
 [1] faKiv:2101.07793 [pdf]

Observers and the mystery of electrical energy loss in the quantumcritical QCDComments: 8 pages, 7 figures
The subject of observerindependent energy loss in the quantumcritical QCD is still a mystery and physicists are still trying to understand how and when energy is lost. We investigate the problem by using systematic techniques of quantum field theory, and we show that the observerinduced energy loss can be understood in terms of the entanglement entropy and the entanglement entropy for quantumcritical systems. We also show that the entanglement entropy in the quantumcritical QCD can be computed using the constantenergy method.
 [2] faKiv:2101.08722 [pdf]

The Big Bang and the Big Crunch: A New Approach to the Evolutionary EntropyComments: 15 pages, 2 figures
The Big Bang can be interpreted as a period of evolution of the universe after the Big Crunch. This period of evolution is characterized by the emergence of entropy and the creation of a universe of primordial black holes. At the end of the Big Bang, the entropy of the universe becomes dominated by the classical zerotemperature theory of the Big Bang and its Big Crunch. The evolution of the entropy can be characterised by a twostep process: (i) The Big Bang is followed by a period of the evolution of entropy and (ii) The Big Crunch is followed by a period of the evolution of entropy. We provide a new approach to the evolution of entropy using the Big Bang and Big Crunch models, which allows us to interpret the Big Bang as a period of the evolution of entropy at the end of the Big Crunch. This is a much simpler and more direct way to interpret the Big Bang and Big Crunch as periods of the evolution of entropy at the end of the Big Crunch.