[HN Gopher] Mathematicians Prove Hawking Wrong About the Most Ex...
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       Mathematicians Prove Hawking Wrong About the Most Extreme Black
       Holes
        
       Author : worldvoyageur
       Score  : 29 points
       Date   : 2024-08-21 14:50 UTC (8 hours ago)
        
 (HTM) web link (www.quantamagazine.org)
 (TXT) w3m dump (www.quantamagazine.org)
        
       | worldvoyageur wrote:
       | " In principle, a black hole can reach a point where it has as
       | much charge or spin as it possibly can, given its mass. Such a
       | black hole is called "extremal" -- the extreme of the extremes.
       | 
       | These black holes have some bizarre properties. In particular,
       | the so-called surface gravity at the boundary, or event horizon,
       | of such a black hole is zero. "
       | 
       | It had been thought impossible for such black holes to exist.
       | However, new work now demonstrates that such black holes are
       | indeed possible.
       | 
       | None have been found, however. Though this seems unsurprising.
       | How would you detect one?
        
         | floxy wrote:
         | >How would you detect one?
         | 
         | I wonder if the gravitational wave signature of a merger
         | between an extremal black hole with something else would give
         | us any clues.
        
           | observationist wrote:
           | You might see something that appears to fall into nothing,
           | with observable massive fluctuations in gravity - anything
           | close by would get disintegrated, observing such an event
           | would result in a treasure trove of data, as long as it's
           | very, very far away. The secondary damage would be something
           | like a particle accelerator bubble on the scale of multiple
           | solar systems.
        
       | Vecr wrote:
       | Checking this physics on this kind of thing is really hard. The
       | math saying an object can operate does not tell you how the
       | object comes into existence, for example.
        
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       (page generated 2024-08-21 23:01 UTC)