Results 41 to 50 of about 18,336 (194)

ELECTROMAGNETISM AND PERFECT FLUIDS INTERPLAY IN MULTIDIMENSIONAL SPACETIMES [PDF]

The Eleventh Marcel Grossmann Meeting, 2008
We consider fields in (D>2)-dimensional spacetime, whose potential is r-form (skew-symmetric tensor of rank r), the field tensor F being its exterior derivative and the Lagrangian, a function of the quadratic invariant I of this tensor. It is shown that vector field (r=1) describes electromagnetic field only for D=4.
openaire   +2 more sources

Matter ouside a Static Higher-dimensional Black Hole

, 2012
We considered matter fields composed of a perfect fluid in the static higher-dimensional spherically symmetric asymptotically flat black hole spacetime.
Rogatko, Marek
core   +1 more source

Static circularly symmetric perfect fluid solutions with an exterior BTZ metric [PDF]

, 2004
In this work we study static perfect fluid stars in 2+1 dimensions with an exterior BTZ spacetime. We found the general expression for the metric coefficients as a function of the density and pressure of the fluid.
A. Garcia, J. Carminati, José R. Villanueva, K. Lake, M. Bañados, M. Lubo, M.S.R. Delgaty, Marco Olivares, N. Cruz, N.J. Cornish, Norman Cruz, P.M. Sá, R. Adler, S. Rahman, W. Israel   +14 more
core   +1 more source

Dressing a Naked Singularity: an Example

, 2009
Considering the evolution of a perfect fluid with self-similarity of the second kind, we have found that an initial naked singularity can be trapped by an event horizon due to collapsing matter.
C. F. C. BRANDT, JAIME F. VILLAS DA ROCHA, M. F. A. DA SILVA, Penrose R., R. CHAN   +4 more
core   +1 more source

Systemic Governance From Below: Story Telling to Empower Access to the Commons Through Mapping and Modelling: A Mixed Methods Approach

Systems Research and Behavioral Science, EarlyView.
ABSTRACT Access to forests, farming land and the Citarum river is limited in Tarumajaya; furthermore, many do not own their own housing and are dependent on the public and private landowners in the area. The region of Tarumajaya faces significant challenges in access to crucial resources such as forests, farming land and the Citarum river, leading to a
Rudolf Wirawan, Janet Judy McIntyre‐Mills, R. Riswanda R. Riswanda, Ida Widianingsih, Indra Gunawan   +4 more
wiley   +1 more source

Cylindrically symmetric perfect-fluid universes [PDF]

, 2000
The aim of this paper is to examine some obtained exact solutions of the Einstein-Maxwell equations, especially their properties from a chronological point of view.
Banerjee A, Bonnor W B, Hawking S W, Horský J, J Horský, Kramer D, Krasinski A, Mitskievic N V, P Klepác, Wright J P   +9 more
core   +2 more sources

Aggregation and the Structure of Value

Noûs, EarlyView.
ABSTRACT Roughly, the view I call “Additivism” sums up value across time and people. Given some standard assumptions, I show that Additivism follows from two principles. The first says that how lives align in time cannot, in itself, matter. The second says, roughly, that a world cannot be better unless it is better within some period or another.
Weng Kin San
wiley   +1 more source

Geometric Classifications of Perfect Fluid Space-Time Admit Conformal Ricci-Bourguignon Solitons

Journal of Mathematics
This paper is dedicated to the study of the geometric composition of a perfect fluid space-time with a conformal Ricci-Bourguignon soliton, which is the extended version of the soliton to the Ricci-Bourguignon flow.
Noura Alhouiti, Soumendu Roy, Santu Dey, Fatemah Mofarreh, Akram Ali, Yanlin Li   +5 more
doaj   +1 more source

Anisotropic solutions in symmetric teleparallel $$f\left( Q\right) $$ f Q -theory: Kantowski–Sachs and Bianchi III LRS cosmologies

European Physical Journal C: Particles and Fields, 2023
We investigate the existence of anisotropic self-similar exact solutions in symmetric teleparallel $$f\left( Q\right) $$ f Q -theory. For the background geometry we consider the Kantowski–Sachs and the Locally Rotationally Symmetric Bianchi type III ...
N. Dimakis, M. Roumeliotis, A. Paliathanasis, T. Christodoulakis   +3 more
doaj   +1 more source

Relativistic hydrodynamics on spacelike and null surfaces: Formalism and computations of spherically symmetric spacetimes

, 1999
We introduce a formulation of Eulerian general relativistic hydrodynamics which is applicable for (perfect) fluid data prescribed on either spacelike or null hypersurfaces.
C. W. Misner, E. Chow, E. Gourgoulhon, E. Seidel, F. Banyuls, F. C. Michel, F. Eulderink, G. B. Cook, H. Bondi, H. Bondi, J. A. Font, J. A. Font, J. A. Font, J. C. Miller, J. Ma. Martí, J. Ma. Martí, J. Ma. Martí, J. R. Wilson, J. Thornburg, J. Winicour, José A. Font, K. New, K. Thorne, L. A. Tamburino, L. A. Tamburino, M. A. Scheel, M. Dubal, M. Ruffert, N. Bishop, P. Anninos, P. J. Mann, P. L. Roe, P. Laguna, P. Papadopoulos, P. Papadopoulos, Philippos Papadopoulos, R. A. Isaacson, R. D. Richtmyer, R. Donat, R. Donat, R. Gómez, R. Gómez, R. K. Sachs, R. L. Marsa, S. Bonazzola, S. K. Godunov   +45 more
core   +1 more source