Show/Hide Menu
Hide/Show Apps
Logout
Türkçe
Türkçe
Search
Search
Login
Login
OpenMETU
OpenMETU
About
About
Open Science Policy
Open Science Policy
Open Access Guideline
Open Access Guideline
Postgraduate Thesis Guideline
Postgraduate Thesis Guideline
Communities & Collections
Communities & Collections
Help
Help
Frequently Asked Questions
Frequently Asked Questions
Guides
Guides
Thesis submission
Thesis submission
MS without thesis term project submission
MS without thesis term project submission
Publication submission with DOI
Publication submission with DOI
Publication submission
Publication submission
Supporting Information
Supporting Information
General Information
General Information
Copyright, Embargo and License
Copyright, Embargo and License
Contact us
Contact us
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
Metadata
Show full item record
This work is licensed under a
Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License
.
Item Usage Stats
194
views
0
downloads
Cite This
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
Suggestions
OpenMETU
Core
A physical model for dimensional reduction and its effects on the observable parameters of the universe
Karaca, Koray; Bayın, Selçuk; Department of Physics (2005)
In this thesis, assuming that higher spatial dimensions existed only during the inflationary prematter phases of the universe, we construct a (1+D)-dimensional (D>3), nonsingular, homogeneous and isotropic Friedmann model for dimensional reduction. In this model, dimensional reduction occurs in the form of a phase transition that follows from a purely thermodynamical consideration that the universe heats up during the inflationary prematter phases. When the temperature reaches its Planck value Tpl,D, which ...
An open inflationary model for dimensional reduction and its effects on the observable parameters of the universe
Karaca, K; Bayin, S (World Scientific Pub Co Pte Lt, 2005-04-30)
Assuming that higher dimensions existed in the early stages of the universe where the evolution was inflationary, we construct an open, singularity-free, spatially homogeneous and isotropic cosmological model to study the effects of dimensional reduction that may have taken place during the early stages of the universe. We consider dimensional reduction to take place in a stepwise manner and interpret each step as a phase transition. By imposing suitable boundary conditions we trace their effects on the pre...
A theoretical study on nitrourea and its tautomers
Türker, Burhan Lemi; Gumus, Selcuk; Atalar, Taner; Atlanel, Sencer (Informa UK Limited, 2008-01-01)
In the present study, nitrourea and its possible tautomers have been subjected to theoretical analysis by performing Hartree-Fock and also density functional theory (DFT) calculations. The optimized geometries, vibrational frequencies, and some thermodynamical values for the presently considered species have been obtained in their ground states.
On the universality of low-energy string model
Dereli, T; Obukhov, YN (IOP Publishing, 2000-01-07)
The low-energy (bosonic 'heterotic') string theory is interpreted as a universal limit of the Kaluza-Klein reduction when the dimension of an internal space goes to infinity. We show that such an approach is helpful in obtaining classical solutions of the string model. As a particular application, we obtain new exact static solutions for the two-dimensional effective string model. They turn out to be in agreement with the generalized no-hair conjecture, in complete analogy with the four- and higher-dimensio...
A First-Order Linear Model for the Estimation of Detonation Velocity
Türker, Burhan Lemi (Informa UK Limited, 2011-01-01)
A linear multivariable model has been derived for the estimation of detonation velocity. Then, its two simplified forms, first-order linear models, have been proposed as estimators of detonation velocities of a large population of explosives having different skeletal structures. Then, the models are analyzed mathematically and regression equations are obtained and discussed. The first model possesses two independent variables E/M and density, whereas the second one is based on E/M only. The total energy (E)...
Citation Formats
IEEE
ACM
APA
CHICAGO
MLA
BibTeX
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.