Results 71 to 80 of about 18,336 (194)
Odessa Astronomical Publications, 2017 The physical properties of an exact solution of Einstein's field equations are examined. This spherically symmetric perfect fluid solution contains expansion, acceleration and shear. There exist models with regions of spacetime where the pressure and the
H. Knutsen
doaj +1 more source
Riemann solitons on perfect fluid spacetimes
FilomatIn this article, we characterize Riemann solitons on perfect fluid spacetimes. Some relationship between perfect fluid spacetimes and Riemann solitons with certain soliton vector fields are established. We investigate Ricci-symmetric perfect fluid spacetimes whose metrics are Riemann solitons.
Avijit Sarkar, Urmila Biswas
openaire +1 more source
One‐dimensional Carrollian fluids II: C1$C^1$ blow‐up criteria
Journal of the London Mathematical Society, Volume 112, Issue 5, November 2025.Abstract The Carrollian fluid equations arise from the equations for relativistic fluids in the limit as the speed of light vanishes, and have recently experienced a surge of interest in the theoretical physics community in the context of asymptotic symmetries and flat‐space holography.
Nikolaos Athanasiou +3 more
wiley +1 more source
Cosmological analysis of scalar field models in f(R, T) gravity
European Physical Journal C: Particles and Fields, 2017 This paper determines the existence of Noether symmetry in non-minimally coupled f(R, T) gravity admitting minimal coupling with scalar field models. We consider a generalized spacetime which corresponds to different anisotropic and homogeneous universe ...
M. Sharif, Iqra Nawazish
doaj +1 more source
On existence of matter outside a static black hole
, 2006 It is expected that matter composed of a perfect fluid cannot be at rest outside of a black hole if the spacetime is asymptotically flat and static (non-rotating).
Gilbarg D. +3 more
core +1 more source
Holomorphic field theories and higher algebra
Bulletin of the London Mathematical Society, Volume 57, Issue 10, Page 2903-2974, October 2025.Abstract Aimed at complex geometers and representation theorists, this survey explores higher dimensional analogs of the rich interplay between Riemann surfaces, Virasoro and Kac‐Moody Lie algebras, and conformal blocks. We introduce a panoply of examples from physics — field theories that are holomorphic in nature, such as holomorphic Chern‐Simons ...
Owen Gwilliam, Brian R. Williams
wiley +1 more source
On the Necessity of Phantom Fields for Solving the Horizon Problem in Scalar Cosmologies
Universe, 2019 We discuss the particle horizon problem in the framework of spatially homogeneous and isotropic scalar cosmologies. To this purpose we consider a Friedmann–Lemaître–Robertson–Walker (FLRW) spacetime with possibly non-zero spatial ...
Davide Fermi +2 more
doaj +1 more source
Charged fluids in higher order gravity
European Physical Journal C: Particles and Fields, 2023 We generate the field equations for a charged gravitating perfect fluid in Einstein–Gauss–Bonnet gravity for all spacetime dimensions. The spacetime is static and spherically symmetric which gives rise to the charged condition of pressure isotropy that ...
Shavani Naicker +2 more
doaj +1 more source
Noncommutative fluid dynamics in the K\"{a}hler parametrization
, 2011 In this paper, we propose a first order action functional for a large class of systems that generalize the relativistic perfect fluids in the K\"{a}hler parametrization to noncommutative spacetimes.
A. Connes +6 more
core +1 more source
MAKING AN ACCESSIBLE CITY: A Critique of Cartographic Reason through Emphasis on Corpography
International Journal of Urban and Regional Research, Volume 49, Issue 5, Page 1109-1128, September 2025.Abstract Inspired by Gunnar Olsson, this article critiques the use of cartographic reason in the process of creating an accessible city for people with disabilities. It also borrows Gregory's ontological conceptual pair of cartography and corpography, showing the ontological transformations that occur within this pair during the practical removal of ...
Pavel Doboš, Robert Osman
wiley +1 more source