A physical model for dimensional reduction and its effects on the observable parameters of the universe

Date

2008-04-01

Author

Karaca, Koray
Bayin, Selcuk

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We construct a physical model to study the effects of dimensional reduction that might have taken place during the inflationary phase of the universe. The model we propose is a (1 + D)-dimensional (D > 3), nonsingular, spatially homogeneous and isotropic Friedmann model. We consider dimensional reduction to take place in a stepwise manner and interpret each step as a phase transition. Independent of the details of the process of dimensional reduction, we impose suitable boundary conditions across the transitions and trace the effects of dimensional reduction to the currently observable parameters of the universe. In order to exhibit the cosmological features of the proposed model, we construct a (1 + 4)-dimensional toy model for both closed and open cases of Friedmann geometries. It is shown that in these models the universe makes transition into the lower dimension when the critical length parameter l(4,3), which signals dimensional reduction, reaches the Planck length in D = 3. The numerical models we present in this paper have the capability of making definite predictions about the cosmological parameters of the universe such as the Hubble parameter, age and density.

Subject Keywords

Physics and Astronomy (miscellaneous)

URI

https://hdl.handle.net/11511/65553

Journal

GENERAL RELATIVITY AND GRAVITATION

DOI

https://doi.org/10.1007/s10714-007-0532-1

Collections

Department of Physics, Article

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Citation Formats

K. Karaca and S. Bayin, “A physical model for dimensional reduction and its effects on the observable parameters of the universe,” GENERAL RELATIVITY AND GRAVITATION, pp. 799–831, 2008, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/65553.