International Journal of Astrophysics and Space Science
Volume 6, Issue 6, December 2018, Pages: 93-100
Received: Nov. 6, 2018;
Accepted: Nov. 19, 2018;
Published: Jan. 7, 2019
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Chifu Ebenezer Ndikilar, Physics Department, Federal University Dutse, Dutse, Nigeria
Abu Ovansa Samson, Physics Department, Gombe State University, Gombe, Nigeria
Hafeez Yusuf Hafeez, Physics Department, Federal University Dutse, Dutse, Nigeria; SRM Research Institute, SRM Institute of Science and Technology, Kattankulathur, India
Singularities in three non-Schwarzschild space-times: Minkowski, Friedman-Lemaitre-Robertson-Walker and Reissner-Nordstromare investigated. Gravitational collapse in the Schwarzschild solution is obvious and widely studied. However, gravitational collapse should not be limited to Schwarzschild solution only as interesting findings exist in other metric fields. The Ricci curvature scalar for each space-time is evaluated and used in the determination of true curvature singularities. The Ricci scalar has proved to be very effective in determining the presence of singularities or otherwise in space-time geometry. Results indicate that there are inherent singularities in components of space-time in all three cases. Gravitational singularities in Minkowski space are found to be consequences of the choice of coordinate. Minkowksi space possesses only coordinate singularities and no curvature singularity. This differs with Schwarzschild’s metric which has true curvature singularity. Friedman-Lemaitre-Robertson-Walker (FLRW) and Reissner-Nordstrom metrics have true curvature singularities. Gravitational collapse in the FLRW metric yields a curvature singularity which shows the universe started a finite time ago. Cosmic strings, white holes and blackholes are deduced from the Reissner-Nordstrom singularities. Reissner-Nordstrom solution show that the addition of small amounts of electric charge or angular momentum could completely alter the nature of the singularity, causing the matter to fall through a ‘wormhole’ and emerge into another universe. Analysis of gravitational collapse in this article provides one of the most exciting research frontiers in gravitation physics and high energy astrophysics; as the debate on their physical existence persists.
Chifu Ebenezer Ndikilar,
Abu Ovansa Samson,
Hafeez Yusuf Hafeez,
Gravitational Collapse and Singularities in Some Non-Schwarzschild's Space-Times, International Journal of Astrophysics and Space Science.
Vol. 6, No. 6,
2018, pp. 93-100.
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