# Third quantization for scalar and spinor wave functions of the Universe in an extended minisuperspace

@inproceedings{Kan2021ThirdQF, title={Third quantization for scalar and spinor wave functions of the Universe in an extended minisuperspace}, author={Nahomi Kan and Takuma Aoyama and Taiga Hasegawa and Kiyoshi Shiraishi}, year={2021} }

We consider the third quantization in quantum cosmology of a minisuperspace extended by the Eisenhart–Duval lift. We study the third quantization based on both Klein–Gordon type and Dirac-type equations in the extended minisuperspace. Spontaneous creation of “universes” is investigated upon the quantization of a simple model. We find that the quantization of the Dirac-type wave function reveals that the number density of universes is expressed by the Fermi–Dirac distribution. We also calculate…

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## References

SHOWING 1-10 OF 53 REFERENCES

Quantum field theory of the Universe.

- Physics, MedicinePhysical review. D, Particles and fields
- 1989

The problematical interpretation of the wave function of the Universe is circumvented by introducing an internal comoving model detector, which is an analogue of the DeWitt-Unruh detector in quantum field theory in curved space-time.

Quantum Gravity

- Physics
- 2002

General lectures on quantum gravity. 1 General Questions on Quantum Gravity It is not clear at all what is the problem in quantum gravity (cf. [3] or [8] for general reviews, written in the same…

Spectrum of wormholes.

- Physics, MedicinePhysical review. D, Particles and fields
- 1990

Wormholes have been studied mainly in the semiclassical approximation as solutions of the classical Euclidean field equations, but one can represent wormholes in a more general manner as Solutions of the Wheeler-DeWitt equation with appropriate boundary conditions.

Wave packets in minisuperspace.

- Physics, MedicinePhysical review. D, Particles and fields
- 1988

It is meaningless in minisuperspace of quantum gravity to extend classical paths through this region to a recollapsing phase and higher degrees of freedom are introduced which can produce classical paths by continuous measurement.

Eisenhart-Duval lift for minisuperspace quantum cosmology

- PhysicsPhysical Review D
- 2021

Takuma Aoyama, Taiga Hasegawa, and Kiyoshi Shiraishi Graduate School of Sciences and Technology for Innovation, Yamaguchi University, Yamaguchi-shi, Yamaguchi 753–8512, Japan (Dated: July 29, 2021)…

Equivalence of a harmonic oscillator to a free particle and Eisenhart lift

- PhysicsAnnals of Physics
- 2021

It is widely known in quantum mechanics that solutions of the Schrödinger equation (SE) for a linear potential are in one-to-one correspondence with the solutions of the free SE. The physical reason…

Creation of universes from the third-quantized vacuum

- Physics
- 2020

We calculate the average numbers of closed, flat, and open universes spontaneously created from nothing in third quantization. The creation of universes is exponentially suppressed for large values…

Doubleverse entanglement in third quantized non-minimally coupled varying constants cosmologies

- Physics
- 2020

In this paper we consider a third quantized cosmological model with varying speed of light $c$ and varying gravitational constant $G$ both represented by non-minimally coupled scalar fields. The…

Initial conditions of inflation in a Bianchi I Universe

- Physics
- 2020

We investigate the initial conditions of inflation in a Bianchi~I universe that is homogeneous but not isotropic. We use the Eisenhart lift to describe such a theory geometrically as geodesics on a…