Superposition of FLRW universes

Date

2020-06-01

Author

GÜRSES, METİN
Heydarzade, Yaghoub
Tekin, Bayram

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We show that (1) the Einstein field equations with a perfect fluid source admit a nonlinear superposition of two distinct homogenous Friedman-Lemaitre-Robertson-Walker (FLRW) metrics as a solution, (2) the superposed solution is an inhomogeneous geometry in general, (3) it reduces to a homogeneous one in the two asymptotes which are the early and the late stages of the universe as described by two different FLRW metrics, (4) the solution possesses a scale factor inversion symmetry and (5) the solution implies two kinds of topology changes: one during the time evolution of the superposed universe and the other occurring in the asymptotic region of space.

Subject Keywords

Astronomy and Astrophysics

URI

https://hdl.handle.net/11511/39972

Journal

JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS

DOI

https://doi.org/10.1088/1475-7516/2020/06/060

Collections

Department of Physics, Article

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Citation Formats

M. GÜRSES, Y. Heydarzade, and B. Tekin, “Superposition of FLRW universes,” JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS, pp. 0–0, 2020, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/39972.