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Re: Massive gamma ray burst detected after black hole merger

Followups directed to: sci.physics.relativity

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7 wrote:

> Thomas 'PointedEars' Lahn wrote:
>>> As I was saying before, when black holes try to merge,
>> Black holes do not “try to” merge; either they merge or they do not. 
>> They do not have will, but just have to follow laws of nature.  Saying
>> that black holes try to merge is as nonsensical as saying that a ball
>> dropped tries to fall down.
> 
> Well if it didn't try, it couldn't have fallen.

Incorrect.

It falls according to Newton’s laws of motion and of universal gravitation 
because the force of gravity caused by its mass and the mass of the body it 
is falling towards pulls on it (and the body it is falling towards; which 
equally falls towards the ball, but we can approximate and neglect that if 
its mass is much greater than that of the ball).

It falls according to general relativity because one of the geodesics of the 
spacetime that is curved by the energy–momentum of both it and of the body 
it is falling towards (again, actually they fall towards each other) then 
ends in or near the center of mass of that body, and there is *no* force 
that *prevents* the ball from having a spacetime trajectory that follows 
that geodesic.

So nothing is tried there at all by anything.  The laws of nature, as we 
discern them, just are.  Ascribing a will of trying to an inanimate object 
like a black hole or a ball, that way lies madness.
 
> Ergo your shiiite logic is full of black holes.

Ex falso quodlibet.  (You should also be more careful.  “Shiiite” can be 
easily misread and misunderstood to refer to religion.)

>>> the net gravity in the middle between the two black holes fall off
>>> to zero […]
>> 
>> How did you get that idea?
> 
> You know I did some thought experiments with a planets
> and figured the centre of a planet has zero gravity.

Imprecise at best.  There is no *net* force on a test mass in the center *of 
mass* of a planet because the gravitational forces pulling from all sides 
*cancel each other out*.  However, as I just stated, there is still gravity 
there, and in GR terms the spacetime curvature reaches a local maximum 
there.

> That was on top of being taught this in physics classes
> deriving formula for the relation which is a linear decay function.

Not even wrong.

> Ergo black hole gravity collapses in the same way when
> black holes are trying to merge.

Black holes are based on general relativity, not Newtonian gravity, so 
saying that “black holes gravity collapses” is *at least* referring to an 
ill-defined concept.

What actually happens is that the curvature of spacetime increases towards 
the singularity of the black hole where it approaches positive infinity.  
That means that as black holes merge, the spacetime curvatures of the black 
holes *add up*.  Given that the curvature is positive in and around both 
black holes, how could it become zero between them as they get closer 
together and finally merge?

> So says elementary physics.

No, it does not.  Elementary mathematics, on the other hand, says that you 
are wrong because 1 + 1 > 0.

Black holes are a topic of general relativity: F'up2 sci.physics.relativity.


PointedEars
-- 
“Science is empirical: knowing the answer means nothing;
 testing your knowledge means everything.”
   —Dr. Lawrence M. Krauss, theoretical physicist,
    in “A Universe from Nothing” (2009)

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Massive gamma ray burst detected after black hole merger 7 <7@enemygadgets.com> - 2016-02-27 09:33 +0000
  Massive gamma ray burst detected after black hole merger HVAC <mr.hvac@gmail.com> - 2016-02-27 03:40 -0800
    Re: Massive gamma ray burst detected after black hole merger 7 <7@enemygadgets.com> - 2016-02-27 12:30 +0000
      Re: Massive gamma ray burst detected after black hole merger john <johnsefton288@gmail.com> - 2016-02-27 04:47 -0800
        Re: Massive gamma ray burst detected after black hole merger HVAC <mr.hvac@gmail.com> - 2016-02-27 05:06 -0800
        Re: Massive gamma ray burst detected after black hole merger Sam Wormley <swormley1@gmail.com> - 2016-02-27 08:04 -0600
      Re: Massive gamma ray burst detected after black hole merger HVAC <mr.hvac@gmail.com> - 2016-02-27 05:02 -0800
        Re: Massive gamma ray burst detected after black hole merger 7 <7@enemygadgets.com> - 2016-02-27 13:35 +0000
          Re: Massive gamma ray burst detected after black hole merger HVAC <mr.hvac@gmail.com> - 2016-02-27 06:01 -0800
            Re: Massive gamma ray burst detected after black hole merger 7 <7@enemygadgets.com> - 2016-02-27 16:37 +0000
              Re: Massive gamma ray burst detected after black hole merger HVAC <mr.hvac@gmail.com> - 2016-02-27 09:17 -0800
              Re: Massive gamma ray burst detected after black hole merger HVAC <mr.hvac@gmail.com> - 2016-02-27 09:30 -0800
            Re: Massive gamma ray burst detected after black hole merger benj <none@gmail.com> - 2016-02-27 15:16 -0500
              Re: Massive gamma ray burst detected after black hole merger Sam Wormley <swormley1@gmail.com> - 2016-02-27 18:56 -0600
              Re: Massive gamma ray burst detected after black hole merger Odd Bodkin <bodkinodd@gmail.com> - 2016-02-29 09:00 -0600
                Re: Massive gamma ray burst detected after black hole merger HVAC <mr.hvac@gmail.com> - 2016-02-29 07:08 -0800
          Re: Massive gamma ray burst detected after black hole merger Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-02-27 17:15 +0100
            Re: Massive gamma ray burst detected after black hole merger 7 <7@enemygadgets.com> - 2016-02-27 16:26 +0000
              Re: Massive gamma ray burst detected after black hole merger Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-02-27 17:51 +0100
                Re: Massive gamma ray burst detected after black hole merger 7 <7@enemygadgets.com> - 2016-02-27 18:13 +0000
      Re: Massive gamma ray burst detected after black hole merger Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-02-27 17:13 +0100
        Re: Massive gamma ray burst detected after black hole merger 7 <7@enemygadgets.com> - 2016-02-27 16:22 +0000
          Re: Massive gamma ray burst detected after black hole merger Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-02-27 17:53 +0100
            Re: Massive gamma ray burst detected after black hole merger john <johnsefton288@gmail.com> - 2016-02-27 09:07 -0800
              Re: Massive gamma ray burst detected after black hole merger HVAC <mr.hvac@gmail.com> - 2016-02-27 09:26 -0800
              Re: Massive gamma ray burst detected after black hole merger Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-02-27 18:47 +0100
              Re: Massive gamma ray burst detected after black hole merger Odd Bodkin <bodkinodd@gmail.com> - 2016-02-27 11:56 -0600
            Re: Massive gamma ray burst detected after black hole merger 7 <7@enemygadgets.com> - 2016-02-27 18:01 +0000
              Re: Massive gamma ray burst detected after black hole merger Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-02-27 19:06 +0100
                Re: Massive gamma ray burst detected after black hole merger 7 <7@enemygadgets.com> - 2016-02-27 18:16 +0000
                Re: Massive gamma ray burst detected after black hole merger Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-02-27 19:39 +0100
  Re: Massive gamma ray burst detected after black hole merger Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-02-27 17:09 +0100
    Re: Massive gamma ray burst detected after black hole merger 7 <7@enemygadgets.com> - 2016-02-27 16:18 +0000
      Re: Massive gamma ray burst detected after black hole merger Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-02-27 18:22 +0100
        Re: Massive gamma ray burst detected after black hole merger "hanson" <hanson@quick.net> - 2016-02-27 10:55 -0800
  Re: Massive gamma ray burst detected after black hole merger Yousuf Khan <bbbl67@spammenot.yahoo.com> - 2016-02-27 19:52 -0500
    Re: Massive gamma ray burst detected after black hole merger 7 <7@enemygadgets.com> - 2016-02-28 10:09 +0000
      Re: Massive gamma ray burst detected after black hole merger Yousuf Khan <bbbl67@spammenot.yahoo.com> - 2016-02-29 10:48 -0500
  Re: Massive gamma ray burst detected after black hole merger Sylvia Else <sylvia@not.at.this.address> - 2016-02-28 11:59 +1100
    Re: Massive gamma ray burst detected after black hole merger 7 <7@enemygadgets.com> - 2016-02-28 10:05 +0000
      Re: Massive gamma ray burst detected after black hole merger Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-02-28 14:39 +0100
  Re: Massive gamma ray burst detected after black hole merger "reber g=emc^2" <herbertglazier0@gmail.com> - 2016-02-29 09:59 -0800
    Re: Massive gamma ray burst detected after black hole merger Sam Wormley <swormley1@gmail.com> - 2016-02-29 12:01 -0600
    Re: Massive gamma ray burst detected after black hole merger Sam Wormley <swormley1@gmail.com> - 2016-02-29 20:01 -0600
  Re: Massive gamma ray burst detected after black hole merger "reber g=emc^2" <herbertglazier0@gmail.com> - 2016-03-01 11:34 -0800
    Re: Massive gamma ray burst detected after black hole merger HVAC <mr.hvac@gmail.com> - 2016-03-01 14:10 -0800

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