127 research outputs found
Bergmann-Thomson energy-momentum complex for solutions more general than the Kerr-Schild class
In a very well-known paper, Virbhadra's research group proved that the
Weinberg, Papapetrou, Landau and Lifshitz, and Einstein energy-momentum
complexes ``coincide'' for all metrics of Kerr-Schild class. A few years later,
Virbhadra clarified that this ``coincidence'' in fact holds for metrics more
general than the Kerr-Schild class. In the present paper, this study is
extended for the Bergmann-Thomson complex and it is proved that this complex
also ``coincides'' with those complexes for a more general than the Kerr-Schild
class metric.Comment: RevTex, 12 page
Energy Distribution of a Stationary Beam of Light
Aguirregabiria et al showed that Einstein, Landau and Lifshitz, Papapetrou,
and Weinberg energy-momentum complexes coincide for all Kerr-Schild metric.
Bringely used their general expression of the Kerr-Schild class and found
energy and momentum densities for the Bonnor metric. We obtain these results
without using Aguirregabiria et al results and verify that Bringley's results
are correct. This also supports Aguirregabiria et al results as well as
Cooperstock hypothesis. Further, we obtain the energy distribution of the
space-time under consideration.Comment: Latex, no figures [Admin note: substantial overlap with gr-qc/9910015
and hep-th/0308070
Language of instruction: A critical aspect of epistemological access to higher education in South Africa
The article discusses language as a critical aspect of epistemological access to higher education in South Africa through a critical analysis of students’ views on language preferences and attitudes at Durban University of Technology (DUT). Language of instruction at higher education institutions is one amongst a plethora of challenges faced in providing equity in higher education in a socially divided post-apartheid South Africa. This discussion of language and access takes place within broader epistemological access challenges faced in South African higher education. The data generated by 45 semi-structured interviews with undergraduate students from six faculties was collected as part of an institution-wide “Who are our students?” research project. The phenomenological thematic analysis arose from the three research questions asked: what is your home language and what language would you prefer to be taught in and why? Some students did not provide an explanation for their choice as they felt it was self-evident, while some provided interesting reasons for their choices. A critical analysis of the findings using Morrow’s epistemological access theory is conducted against the backdrop of the context of English dominance over indigenous languages; the history of South African higher education, current DUT and higher education policy as it pertains to language and the subsequent challenges around equitable access
Energy distribution of charged dilaton black holes
Chamorro and Virbhadra studied, using the energy-momentum complex of
Einstein, the energy distribution associated with static spherically symmetric
charged dilaton black holes for an arbitrary value of the coupling parameter
which controls the strength of the dilaton to the Maxwell field. We
study the same in Tolman's prescription and get the same result as obtained by
Chamorro and Virbhadra. The energy distribution of charged dilaton black holes
depends on the value of and the total energy is independent of this
parameter.Comment: 8 pages, RevTex, no figure
M{\o}ller Energy for the Kerr-Newman metric
The energy distribution in the Kerr-Newman space-time is computed using the
M{\o}ller energy-momentum complex. This agrees with the Komar mass for this
space-time obtained by Cohen and de Felice. These results support the
Cooperstock hypothesis.Comment: 8 pages, 1 eps figure, RevTex, accepted for publication in Mod. Phys.
Lett.
- …