I Opposite of Black Hole - Matter Repulsion?

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Since black holes takes matter to a singularity, theoretically could there be a hole that does the opposite? As in push everything away like negative pressure.
 
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Oh cool! Thanks!
 
Drakkith said:
A white hole, which does exactly what you proposed

Not really. A white hole has attractive gravity, not repulsive gravity. See below.

Felix Quintana said:
could there be a hole that does the opposite? As in push everything away like negative pressure.

No. A black hole, and its time reverse, a white hole, are both vacuum solutions; there is zero pressure everywhere (and also zero energy density). The white hole has things coming out of it and decelerating as they rise away. The black hole has things falling into it and accelerating as they fall. Gravity is attractive in both cases.

For a solution with "negative pressure", you need either a cosmological constant or something like a scalar field, i.e., not vacuum.
 
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