Zobrazeno 1 - 10
of 37
pro vyhledávání: '"Woei Chet Lim"'
We consider a dynamical systems formulation for models with an exponential scalar field and matter with a linear equation of state in a spatially flat and isotropic spacetime. In contrast to earlier work, which only considered linear hyperbolic fixed
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::f39caf32863b1de709a75224e37795b3
Autor:
Woei Chet Lim
We produce numerical evidence that the joint spike transitions between Kasner eras of $G_2$ cosmologies are described by the non-orthogonally transitive $G_2$ spike solution. A new matching procedure is developed for this purpose.
Comment: 18 pa
Comment: 18 pa
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::30aec8cbb9fb196a276b6ffbc1e4c751
Autor:
Woei Chet Lim, Zubair Moughal
We use the technique developed in Moughal's doctoral thesis to analyse the joint spike transition, revealing new groups of worldlines which undergo distinct transitions, and correcting misconceptions about spikes.
20 pages, 9 figures. Accepted b
20 pages, 9 figures. Accepted b
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::cbeca932c56ab41fd95d777928747480
http://arxiv.org/abs/2111.15122
http://arxiv.org/abs/2111.15122
Autor:
Woei Chet Lim, Zubair Moughal
The Geroch/Stephani transformation is a solution-generating transformation, and may generate spiky solutions. The spikes in solutions generated so far are either early-time permanent spikes or transient spikes. We want to generate a solution with a l
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::f3e180083ee95f5db46f0f06e6f6721e
http://arxiv.org/abs/2102.12028
http://arxiv.org/abs/2102.12028
In this paper we expand upon our previous work [1] by using the entire family of Bianchi type V stiff fluid solutions as seed solutions of the Stephani transformation. Among the new exact solutions generated, we observe a number of important physical
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::ccfef360d33d5e95143a307c4596d0c8
http://arxiv.org/abs/1705.02747
http://arxiv.org/abs/1705.02747
Using the Geroch transformation we obtain the first example of an exact stiff fluid spike solution to the Einstein field equations in a closed form exhibiting a spacelike $G_1$ group of symmetries (i.e., with a single isometry). This new solution is
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::d8928f924412d6e0b30fad12077230b6
http://arxiv.org/abs/1606.07177
http://arxiv.org/abs/1606.07177
Autor:
Alan Coley, Woei Chet Lim
Publikováno v:
Classical and Quantum Gravity. 24:889-895
We investigate the effect of dark energy on the limits on the shear anisotropy in spatially homogeneous Bianchi cosmological models obtained from measurements of the temperature anisotropies in the cosmic microwave background. We shall primarily assu
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::a82722418a6cad3c7035f258c34db99c
https://doi.org/10.1088/0264-9381/24/4/009
https://doi.org/10.1088/0264-9381/24/4/009
Autor:
Alan Coley, Woei Chet Lim
We shall discuss the general relativistic generation of spikes in a massless scalar field or stiff perfect fluid model. We first investigate orthogonally transitive (OT) $G_2$ stiff fluid spike models both heuristically and numerically, and give a ne
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::b156886e1ab2bf328493129fac9abff2
http://arxiv.org/abs/1511.07095
http://arxiv.org/abs/1511.07095
Publikováno v:
Physics Letters B. 638(4):310-313
We show that in tilting perfect fluid cosmological models with an ultra-radiative equation of state, generically the tilt becomes extreme at late times and, as the tilt instability sets in, observers moving with the tilting fluid will experience sing
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::9a049e0935197b3a523f9cc051571b3f
Publikováno v:
Classical and Quantum Gravity. 23:3573-3591
We study perfect fluid cosmological models with a constant equation of state parameter $\gamma$ in which there are two naturally defined time-like congruences, a geometrically defined geodesic congruence and a non-geodesic fluid congruence. We establ
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::0dbf7cc37c5093059d86459aa28eebad
https://doi.org/10.1088/0264-9381/23/10/021
https://doi.org/10.1088/0264-9381/23/10/021