Results 301 to 310 of about 62,947 (343)

The Singularity Problem of Gravitation

Fortschritte der Physik/Progress of Physics, 1988
We review the present status of the singularity problem in gravitation theory. First we repeat the known results for Einstein's theory. After this, different other gravitation theories are considered under the following aspect: Which of the presumptions leading to singularities in Einstein's theory are not fulfilled, and can this prevent the ...
H. Fuchs, U. Kasper, D. -E. Liebscher, V. Müller, H. -J. Schmidt   +4 more
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Singularities in gravitational theory

Russian Physics Journal, 1992
It is shown that in the absolute parallelism theory a unique choice of field equations can be made by requiring that the solutions extend beyond possible singularities, while for the equations of the general theory of relativity and R2-gravitation this condition is not satisfied.
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Gravitation Without Singularity

Chinese Physics Letters, 2000
The coupled Einstein-scalar-vector field equations are found, and their static spherically symmetric solutions are derived under the consideration of self-gravitational interaction of scalar field and proved to be singularity-free and of limited energy.
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On singularities in electrodynamics and gravitational theory

Astronomische Nachrichten, 1979
AbstractThe singularity and particle problems in electrodynamics and gravitational theory are discussed. Comparing different modifications of MAXWELL's electrodynamics and general theory of relativity, arguments are given which show possibilities of solving these problems by a modification that replaces EINSTEIN's equations by those of the EINSTEIN ...
von Borzeszkowski, Horst-Heino, Treder, Hans-Jürgen, Yourgrau, Wolfgang   +2 more
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Foliation analysis of gravitation singularities

Physics Letters A, 1982
Abstract Gravitation singularities are examined as singularities of space-time foliations which represent critical points of real functions on a space-time.
D. Ivanenko, G. Sardanashvily
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Precursory singularities in spherical gravitational collapse

Physical Review Letters, 1992
Summary: General conditions are developed for the formation of naked precursory (``shell-focusing'') singularities in spherical gravitational collapse. These singularities owe their nakedness to the fact that the gravitational potential fails to be single valued prior to the onset of a true gravitational singularity.
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Singularities in Weyl gravitational fields

International Journal of Theoretical Physics, 1974
The peculiarities of the scalarS ≡RijklRijkl are exhibited for two axially-symmetric static (Weyl) gravitational fields. By examiningS along curved families of trajectories to the Weyl singularities, examples are found which contradict previous claims by Gautreau and Anderson regarding ‘directional singularities’.
F. I. Cooperstock, G. J. Junevicus
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Marathe’s generalized gravitational fields and singularities

Il Nuovo Cimento B, 1983
The field equation proposed by Penney and Marathe, the interesting mathematical properties of which have been studied by Marathe, is discussed from an original physical point of view. In particular, this equation is shown to admit solutions which are qualitatively different from analogous solutions of the Einstein equation since they have no ...
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Gravitational Singularities

Index Academic
Gravitational singularities in general relativity are spacetime locations where the gravitational field becomes infinite. Scalar invariant curves of spacetime include a measure of matter density. Some physicists and philosophers believe that because the density of matter tends to become infinite in singularity, spacetime laws are no longer valid there.
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Arnold’s singularity theory and gravitational lensing

Journal of Mathematical Physics, 1993
Caustics in gravitational lensing are formulated from a symplectic geometric viewpoint. Arnold’s singularity theory is then used to give a rigorous local classification of generic gravitational lensing caustics and their evolutions. A local classification is also presented of generic image surfaces, time-delay image surfaces, big caustics, and ...
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