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
An open singularity-free cosmological model with inflation
Download
index.pdf
Date
2002-11-20
Author
Karaca, K
Bayin, S
Metadata
Show full item record
This work is licensed under a
Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License
.
Item Usage Stats
91
views
0
downloads
Cite This
In the light of recent observations which point to an open universe (Omega(0) < 1), we construct an open singularity-free cosmological model by reconsidering a model originally constructed for a closed universe. Our model starts from a nonsingular state called prematter, governed by an inflationary equation of state P = (gamma(p) - 1)rho where gamma(p) (similar or equal to10(-3)) is a small positive parameter representing the initial vacuum dominance of the universe. Unlike the closed models universe cannot be initially static hence, starts with an initial expansion rate represented by the initial value of the Hubble constant H(0). Therefore, our model is a two-parameter universe model (gamma(p), H(0)). Comparing the predictions of this model for the present properties of the universe with the recent observational results, we argue that the model constructed in this work could be used as a realistic universe model.
Subject Keywords
Inflation
,
Flatness
,
Singularity-free
URI
https://hdl.handle.net/11511/66072
Journal
INTERNATIONAL JOURNAL OF MODERN PHYSICS A
DOI
https://doi.org/10.1142/s0217751x0201354x
Collections
Department of Physics, Article
Suggestions
OpenMETU
Core
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 SINGULARITY-FREE COSMOLOGICAL MODEL WITH A CONFORMALLY COUPLED SCALAR FIELD
BAYIN, SS; COOPERSTOCK, FI; FARAONI, V (American Astronomical Society, 1994-06-20)
We explore the possibility of describing our universe with a singularity-free, closed, spatially homogeneous and isotropic cosmological model, using only general relativity and a suitable equation of state which produces an inflationary era. A phase transition to a radiation-dominated era occurs as a consequence of boundary conditions expressing the assumption that the temperature cannot exceed the Planck value. We find that over a broad range of initial conditions, the predicted value of the Hubble paramet...
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 ...
Different approaches to the Einstein energy associated with the de Sitter C-space-time
Salti, M (2005-12-01)
The paper is purposed to elaborate the problem of gravitational energy localization in de Sitter(dS) C-space-time (the C space-time in a background with a cosmological constant Lambda). In this connection, using the energy-momentum definition of Einstein, we find the same energy in both general relativity and tele-parallel gravity.
A physical model for dimensional reduction and its effects on the observable parameters of the universe
Karaca, Koray; Bayin, Selcuk (Springer Science and Business Media LLC, 2008-04-01)
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 transi...
Citation Formats
IEEE
ACM
APA
CHICAGO
MLA
BibTeX
K. Karaca and S. Bayin, “An open singularity-free cosmological model with inflation,”
INTERNATIONAL JOURNAL OF MODERN PHYSICS A
, pp. 4457–4462, 2002, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/66072.