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Re: Record-breaking supermassive black hole found in heart of far-off galaxy

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On 2/12/2016 10:56 AM, Mike Duffy wrote:
> On Fri, 12 Feb 2016 10:26:28 -0600, Odd Bodkin wrote:
>
>> Note, John Sefton, that black holes are not presented in GR as things
>> that swallow everything in their vicinity, and that star formation in
>> the region outside a black hole is perfectly consistent with general
>> relativity.
>
> How does that work? My limited understanding of the mechanism for black
> holes emitting matter via 'Hawking' radiation works best for black holes
> just barely big enough to hold thenselves together. Bigger ones would thus
> emit less.
>

Because of the gravitational pull of the black hole, matter can accrete 
outside the black hole's event horizon WITHOUT being sucked in. This is 
for the same reason that the matter in the rings of Saturn accrete in 
those rings without falling into Saturn, and for the same reason the 
asteroid belt orbits the sun without falling into the sun.

If the density of the accretion is high enough, you can seed stars.

If the black hole has angular momentum, then you can also get effects 
that come from the rotation of the orbiting matter, such as magnetic 
fields and ejected jets along the axis.

None of this has anything to do with Hawking radiation, which (as you 
say) is tiny, tiny, tiny for a supermassive black hole.

-- 
Odd Bodkin --- maker of fine toys, tools, tables

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Thread

Record-breaking supermassive black hole found in heart of far-off galaxy Yousuf Khan <bbbl67@spammenot.yahoo.com> - 2016-02-12 11:21 -0500
  Re: Record-breaking supermassive black hole found in heart of far-off galaxy Odd Bodkin <bodkinodd@gmail.com> - 2016-02-12 10:26 -0600
    Re: Record-breaking supermassive black hole found in heart of far-off galaxy Mike Duffy <Invalid@no_such_domain.com> - 2016-02-12 11:56 -0500
      Re: Record-breaking supermassive black hole found in heart of far-off galaxy Odd Bodkin <bodkinodd@gmail.com> - 2016-02-12 11:09 -0600
      Re: Record-breaking supermassive black hole found in heart of far-off galaxy Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-02-13 01:37 +0100
        Re: Record-breaking supermassive black hole found in heart of far-off galaxy dlzc <dlzc1@cox.net> - 2016-02-13 07:08 -0800
  Re: Record-breaking supermassive black hole found in heart of far-off galaxy Sam Wormley <swormley1@gmail.com> - 2016-02-12 11:02 -0600

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