Holographic Entanglement of a Big Bang Observable Universe

We study the holographic entanglement entropy of a big bang observable universe, which is the entropy of quantum fields in the universe. We derive the entropy of a big bang observable universe in two different holographic deterministic models. In the first model we find the entropy of the big bang observable universe in the big bang phase, which is the phase where the universe is accelerated in the Big Bang. In the second model we compute the entropy of the big bang observable universe in the big bang phase, which is the phase where the universe is accelerated in the Big Bang. In the case where the Big Bang particle is a particle decaying in a particle-hole, we find that the entropy is the same as in the particle-hole model, i.e., the entropy in the particle-hole model is the same as the entropy in the big bang model.