Zobrazeno 1 - 10
of 42
pro vyhledávání: '"Golda, Zdzislaw A."'
Publikováno v:
Acta Physica Polonica B 50 (2019) 885-909
This work deals with intersection points: conjugate points and cut points, of timelike geodesics emanating from a common initial point in special spacetimes. The paper contains three results. First, it is shown that radial timelike geodesics in stati
Externí odkaz:
http://arxiv.org/abs/1901.03533
The work presents the frst and the second degree Darboux polynomials, Jacobi's last multipliers as well as the set of frst integrals for Brans-Dicke cosmology. Algebraic invariant sets are constructed. First integrals are visualized for some particul
Externí odkaz:
http://arxiv.org/abs/1901.00388
Publikováno v:
International Journal of Modern Physics D Vol. 25, No. 1 (2016) 1650007
We refine and analytically prove an old proposition due to Calabi and Markus on the shape of timelike geodesics of anti--de Sitter space in the ambient flat space. We prove that each timelike geodesic forms in the ambient space a circle of the radius
Externí odkaz:
http://arxiv.org/abs/1602.07111
This is a consecutive paper on the timelike geodesic structure of static spherically symmetric spacetimes. First we show that for a stable circular orbit (if it exists) in any of these spacetimes all the infinitesimally close to it timelike geodesics
Externí odkaz:
http://arxiv.org/abs/1404.5808
Publikováno v:
Acta Phys. Polon. B45 (2014) 1051-1075
We investigate local and global properties of timelike geodesics in three static spherically symmetric spacetimes. These properties are of its own mathematical relevance and provide a solution of the physical `twin paradox' problem. The latter means
Externí odkaz:
http://arxiv.org/abs/1402.6511
Publikováno v:
Acta Phys. Polon. B 46(2015) 773-787
Several physical problems such as the `twin paradox' in curved spacetimes have purely geometrical nature and may be reduced to studying properties of bundles of timelike geodesics. The paper is a general introduction to systematic investigations of t
Externí odkaz:
http://arxiv.org/abs/1402.3976
We investigate the initial condition which are simultaneously consistent with perturbation equations in both the radiation-dominated and the mater-dominated epochs. The exact formula for the spectrum transfer-function is derived.
Comment: 7 page
Comment: 7 page
Externí odkaz:
http://arxiv.org/abs/1103.2258
The acoustic spacetime corresponding to perturbed Friedman-Lemaitre-Robertson-Walker universe inherit the space isometries from the original FLRW model, but essentially differs in dynamics. The scale factor manifestly depends on the equation of state
Externí odkaz:
http://arxiv.org/abs/1103.1506
In this paper the acoustic field propagating in the early hot ($p=\epsilon/$) universe of arbitrary space curvature ($K=0, \pm 1$) is considered. The field equations are reduced to the d'Alembert equation in an auxiliary static Roberson-Walker space-
Externí odkaz:
http://arxiv.org/abs/0902.0239
Publikováno v:
Acta Phys.Polon. B36 (2005) 2133-2141
Under an appropriate change of the perturbation variable Lifshitz-Khalatnikov propagation equations for the scalar perturbation reduce to d'Alembert equation. The change of variables is based on the Darboux transform.
Comment: LaTeX, 9 pages
Comment: LaTeX, 9 pages
Externí odkaz:
http://arxiv.org/abs/gr-qc/0511040