Some LRS Bianchi type II string-dust cosmological models with time decaying vacuum energy Λ
A new class of LRS Bianchi type II string- dust cosmological models are obtained in which the expansion (ᶿ) in the model is assumed to be proportional to the shear (σ). To get the deterministic models of the universe we consider the case of Reddy string (ρ + λ = 0), where ρ and λ are the rest energy...
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| Format: | Conference or Workshop Item |
| Language: | English |
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Ibnu Sina Institute for Fundamental Science Studies, Universiti Teknologi Malaysia
2010
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| Online Access: | http://psasir.upm.edu.my/id/eprint/64968/ http://psasir.upm.edu.my/id/eprint/64968/1/2010-2.pdf |
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| author | Amirhashchi, Hassan Dehzangi, Arash |
| author_facet | Amirhashchi, Hassan Dehzangi, Arash |
| author_sort | Amirhashchi, Hassan |
| building | UPM Institutional Repository |
| collection | Online Access |
| description | A new class of LRS Bianchi type II string- dust cosmological models are obtained in which the expansion (ᶿ) in the model is assumed to be proportional to the shear (σ). To get the deterministic models of the universe we consider the case of Reddy string (ρ + λ = 0), where ρ and λ are the rest energy density and the tension density of the string cloud, respectively. It is shown that in all models the vacuum energy density Λ is a positive and decreasing function of time and it approaches a small positive value at late times which is supported by recent results from the observations of (SN Ia). The physical and geometrical behaviour of these models are discussed. |
| first_indexed | 2025-11-15T11:21:14Z |
| format | Conference or Workshop Item |
| id | upm-64968 |
| institution | Universiti Putra Malaysia |
| institution_category | Local University |
| language | English |
| last_indexed | 2025-11-15T11:21:14Z |
| publishDate | 2010 |
| publisher | Ibnu Sina Institute for Fundamental Science Studies, Universiti Teknologi Malaysia |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | upm-649682018-09-03T04:10:05Z http://psasir.upm.edu.my/id/eprint/64968/ Some LRS Bianchi type II string-dust cosmological models with time decaying vacuum energy Λ Amirhashchi, Hassan Dehzangi, Arash A new class of LRS Bianchi type II string- dust cosmological models are obtained in which the expansion (ᶿ) in the model is assumed to be proportional to the shear (σ). To get the deterministic models of the universe we consider the case of Reddy string (ρ + λ = 0), where ρ and λ are the rest energy density and the tension density of the string cloud, respectively. It is shown that in all models the vacuum energy density Λ is a positive and decreasing function of time and it approaches a small positive value at late times which is supported by recent results from the observations of (SN Ia). The physical and geometrical behaviour of these models are discussed. Ibnu Sina Institute for Fundamental Science Studies, Universiti Teknologi Malaysia 2010 Conference or Workshop Item PeerReviewed text en http://psasir.upm.edu.my/id/eprint/64968/1/2010-2.pdf Amirhashchi, Hassan and Dehzangi, Arash (2010) Some LRS Bianchi type II string-dust cosmological models with time decaying vacuum energy Λ. In: Regional Annual Fundamental Science Symposium 2010 (RAFSS 2010), 8-9 June 2010, Grand Season Hotel, Kuala Lumpur. (pp. 139-148). |
| spellingShingle | Amirhashchi, Hassan Dehzangi, Arash Some LRS Bianchi type II string-dust cosmological models with time decaying vacuum energy Λ |
| title | Some LRS Bianchi type II string-dust cosmological models with time decaying vacuum energy Λ |
| title_full | Some LRS Bianchi type II string-dust cosmological models with time decaying vacuum energy Λ |
| title_fullStr | Some LRS Bianchi type II string-dust cosmological models with time decaying vacuum energy Λ |
| title_full_unstemmed | Some LRS Bianchi type II string-dust cosmological models with time decaying vacuum energy Λ |
| title_short | Some LRS Bianchi type II string-dust cosmological models with time decaying vacuum energy Λ |
| title_sort | some lrs bianchi type ii string-dust cosmological models with time decaying vacuum energy λ |
| url | http://psasir.upm.edu.my/id/eprint/64968/ http://psasir.upm.edu.my/id/eprint/64968/1/2010-2.pdf |