37. Piotr T. Chru¶ciel, Sebastian J. Szybka On the Ernst electro-vacuum equations and ergosurfaces Acta Phys. Pol., B , vol. 39, pp. 59-75 (2008). [abstract] [preprint] [journal] |
Abstract: The question of smoothness at the ergosurface of the space-time
metric constructed out of solutions (E,phi) of the Ernst electro-vacuum equations is considered. We prove smoothness of those ergosurfaces at which Re(E) provides the dominant contribution to f=-(Re(E)+|phi|^2) at the zero-level-set of f. Some partial results are obtained in the remaining cases: in particular we give examples of leading-order solutions with singular isolated ``ergocircles". |
38. Sebastian J. Szybka, Tadeusz Chmaj Fractal Threshold Behavior in Vacuum Gravitational Collapse Phys. Rev. Lett., vol. 100, p. 101102 (2008). [abstract] [preprint] [journal] [download] |
Abstract: We present the numerical evidence for fractal threshold behavior in the five dimensional vacuum Einstein equations satisfying the cohomogeneity-two triaxial Bianchi type-IX ansatz. In other words, we show that a flip of the wings of a butterfly may influence the process of the black hole formation. |
39. Andrzej Woszczyna Dispersion of density waves in the Universe with positive cosmological constant Conference report (2008). [abstract] [Mathematica 5.2] |
Abstract: Marie Curie Host Fellowships for the Transfer of Knowledge (TOK)
Project MTKD-CT-2005-029466: PARTICLE PHYSICS AND COSMOLOGY: THE INTERFACE,
Fourth Workshop 13.02 - 16.02.2008, Warszawa |
40. Sebastian J. Szybka Chaos, Gravity and Wave Maps with Target SU(2) Proceedings of the MG11 Meeting on General Relativity (2008). [abstract] [journal] |
Abstract: We present the numerical evidence for chaotic solutions and fractal threshold behavior in the Einstein equations coupled to a wave map (with target SU(2)). This phenomenon is explained in terms of heteroclinic intersections. |
41. Artur Janda On Lie Symmetries of Certain Spherically Symmetric Systems in General Relativity Acta Phys. Pol., B , vol. 38, pp. 3961-3969 (2007). [abstract] [journal] [http://th-www.if.uj.edu.pl/acta/vol38/pdf/v38p3961.pdf] |
Abstract: Certain aspects of Lie-point symmetries in spherically symmetric systems of gravitational physics. Lie symmetries are helpful in solving differential equations. General concepts and a few examples are given: perfect fluid in shearfree motion, the conformal Weyl theory and a higher derivative gravity which is equivalent to General Relativity coupled to certain nonlinear spin-2 field theory. |
42. Jacek Guzik, Gary Bernstein, Robert E. Smith Systematic effects in the sound horizon scale measurements MNRAS, vol. 375, pp. 1329-1337 (2007). [preprint] [journal] |
Abstract:
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