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On Gravitational Repulsion

Tsvi Piran
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Abstract

The concepts of negative gravitational mass and gravitational repulsion are alien to general relativity. Still, we show here that small negative fluctuations - small dimples in the primordial density field - that act as if they have an effective negative gravitational mass, play a dominant role in shaping our Universe. These initially tiny perturbations repel matter surrounding them, expand and grow to become voids in the galaxy distribution. These voids - regions with a diameter of $40 \h$ Mpc which are almost devoid of galaxies - are the largest object in the Universe.

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Tsvi Piran. 1997-06-16. On Gravitational Repulsion. https://doi.org/10.1023/a%3A1018877928270

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