English

Initial wave-function of the universe is arbitrary

High Energy Physics - Theory 2020-02-24 v3 General Relativity and Quantum Cosmology

Abstract

We consider quantization of the gravity-scalar field system in the minisuperspace approximation. It turns out that in the gauge fixed deparametrized theory where the scale factor plays the role of time, the Hamiltonian can be uniquely defined without any ordering ambiguity as the square root of a self-adjoint operator. Moreover, the Hamiltonian degenerates to zero and the Schr\"{o}dinger equation becomes well behaved as the scale factor vanishes. Therefore, there is no technical or physical obstruction for the initial wave-function of the universe to be an arbitrary vector in the Hilbert space, which demonstrates the severeness of the initial condition problem in quantum cosmology.

Keywords

Cite

@article{arxiv.1901.00199,
  title  = {Initial wave-function of the universe is arbitrary},
  author = {Ali Kaya},
  journal= {arXiv preprint arXiv:1901.00199},
  year   = {2020}
}

Comments

6 pages, v3: comments added, the results are generalized to the most general spatially flat minisuperspace model

R2 v1 2026-06-23T07:00:55.288Z