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Re: question about mass in GR - black holes

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alsor@interia.pl wrote:

> W dniu niedziela, 18 marca 2018 17:34:00 UTC+1 użytkownik Thomas
> 'PointedEars' Lahn napisał:
> 
>> The fantasy is yours.  There is *a lot* of *observational evidence* that
>> black holes exist.
>> - Pairs of black holes have been *observed* to *merge* four times now:
> 
> They see very dense, massive objects only, not any black holes.

Objects with large (mass) density *are* black holes in general relativity, 
the theory of which these apparatuses are based, and which they confirm 
*again* through their observations.
 
> Simply:
> for very extreme gravity the potential is near to the limit: -1/2 c^2;

Not even wrong.  You need to *study* what you are talking about.  Your 
uneducated guesses are hopeless.  Gravitational potential, for example,
has units of energy per mass, not length squared per time squared (c is a 
*speed*).

>>   <https://en.wikipedia.org/wiki/Event_Horizon_Telescope>
> 
> There is no practical difference for these stupid humans between black
> hole and some very dens body!

Because there is none.  A body whose radius is smaller than its 
Schwarzschild radius becomes a black hole, period.  Obviously the 
mass/energy density of a small body with a large mass/energy is very high, 
too, as any density is defined as

  ρ = dQ∕dV.

where Q is the quantity whose density is to be measured per unit volume; 
here mass/energy (m/E).

And that the curvature of spacetime corresponds to the density of 
mass/energy, stress, and momentum in spacetime, is the main statement of 
general relativity (about which you have no clue), in the form of the 
Einstein field equations:

  R_µν − (1∕2 R + Λ) g_µν = 8π G∕c⁴ T_µν
              “curvature” = “energy-momentum” (density)

For a perfect fluid:

                     T_00 = ρ

That is, if that density rises above a certain limit, spacetime is curved in 
a way that all geodesics in it lead towards a single spacetime point (inner 
Schwarzschild or Reissner–Nordström metric) or ring (Kerr or Kerr–Newman 
metric) – a *singularity*.  Light follows geodesics, so all light that gets 
beyond the Schwarzschild radius from the outside can never get back – that 
is the *definition* of a *black* hole.

<https://goo.gl/images/UVhe3v>
<https://goo.gl/images/X4g2o5>

<http://jila.colorado.edu/~ajsh/insidebh/>
<http://jila.colorado.edu/~ajsh/bh/schw.html> (link in the above is dead)

<http://hyperphysics.phy-astr.gsu.edu/hbase/Relativ/blahol.html#c1>
<http://hyperphysics.phy-astr.gsu.edu/hbase/Astro/blkhol.html#c2>

> A real limit of size for a massive body - uniform sphere, is just: R = 3m,
> what is practically the same what your stupid: rs = 2m!

3 = 2.  Hopeless case.

>> Gravity is currently best modeled by *general* relativity.  Positron–
>> electron annihilation is currently best modeled by quantum
>> electrodynamics, a *special*-relativistic quantum field theory.
> 
> I told about the standard gravitational redshift in the GR model only,

No, you did not.  You evidently have no clue of basic physics to begin with, 
let alone GR.

<http://hyperphysics.phy-astr.gsu.edu/hbase/Relativ/gratim.html#c1>

> which immediately destroys yours fantasy about BH.

You have no clue what you are talking about.  Go away (and study).
 
> I don't care about 'quantum gravity' at all - it's just another very big
> fallacy in these so-called mainstream... it's by babes invented
> pseudoscience in fact.

No, *you* are the unrivaled master of pseudoscience.  Like when you equate 
the rest energy of a massive body (m > 0) with the emitted frequency of a 
photon (m = 0).


PointedEars
-- 
«Nec fasces, nec opes, sola artis sceptra perennant.»
(“Neither high office nor power, only the scepters of science survive.”)

  —Tycho Brahe, astronomer (1546-1601), inscription at Hven

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question about mass in GR - black holes alsor@interia.pl - 2018-03-07 14:23 -0800
  Re: question about mass in GR - black holes Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-03-08 18:02 +0100
    Re: question about mass in GR - black holes alsor@interia.pl - 2018-03-17 15:16 -0700
      Re: question about mass in GR - black holes Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-03-18 17:33 +0100
        Re: question about mass in GR - black holes Darryl Fletcher <lu@ewiwwe.tt> - 2018-03-18 17:05 +0000
          Re: question about mass in GR - black holes Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-03-18 18:08 +0100
        Re: question about mass in GR - black holes alsor@interia.pl - 2018-03-18 10:49 -0700
          Re: question about mass in GR - black holes Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-03-18 21:02 +0100
            Re: question about mass in GR - black holes alsor@interia.pl - 2018-03-18 14:24 -0700
              Re: question about mass in GR - black holes Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-03-18 22:58 +0100
                Re: question about mass in GR - black holes alsor@interia.pl - 2018-03-19 10:04 -0700
                Re: question about mass in GR - black holes Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-03-20 04:43 +0100
                Re: question about mass in GR - black holes alsor@interia.pl - 2018-03-20 12:42 -0700
                Re: question about mass in GR - black holes Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-03-20 21:03 +0100
                Re: question about mass in GR - black holes alsor@interia.pl - 2018-03-20 14:04 -0700
                Re: question about mass in GR - black holes Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-03-20 23:59 +0100
  Re: question about mass in GR - black holes Tom Roberts <tjroberts137@sbcglobal.net> - 2018-03-08 17:43 -0600
    Re: question about mass in GR - black holes Tom Roberts <tjroberts137@sbcglobal.net> - 2018-03-08 19:51 -0600
      Re: question about mass in GR - black holes Keith Stein <keithstein111@gmail.com> - 2018-03-17 10:20 +0000
    Re: question about mass in GR - black holes mlwozniak@wp.pl - 2018-03-08 21:25 -0800
      Re: question about mass in GR - black holes Python <python@python.invalid> - 2018-03-09 06:31 +0100
    Re: question about mass in GR - black holes alsor@interia.pl - 2018-03-17 15:40 -0700
      Re: question about mass in GR - black holes Tom Roberts <tjroberts137@sbcglobal.net> - 2018-03-18 01:05 -0500
        Re: question about mass in GR - black holes Térov Balónky <iytn@yeicenlw.ik> - 2018-03-18 12:57 +0000
        Re: question about mass in GR - black holes alsor@interia.pl - 2018-03-18 10:23 -0700
          Re: question about mass in GR - black holes "David (Kronos Prime) Fuller" <fuller.david@hotmail.com> - 2018-03-18 10:35 -0700
            Re: question about mass in GR - black holes alsor@interia.pl - 2018-03-18 11:11 -0700
              Re: question about mass in GR - black holes "David (Kronos Prime) Fuller" <fuller.david@hotmail.com> - 2018-03-18 11:18 -0700
                Re: question about mass in GR - black holes "David (Kronos Prime) Fuller" <fuller.david@hotmail.com> - 2018-03-18 11:40 -0700
                Re: question about mass in GR - black holes "David (Kronos Prime) Fuller" <fuller.david@hotmail.com> - 2018-03-18 11:50 -0700
                Re: question about mass in GR - black holes "David (Kronos Prime) Fuller" <fuller.david@hotmail.com> - 2018-03-18 12:29 -0700
                Re: question about mass in GR - black holes alsor@interia.pl - 2018-03-18 11:43 -0700
                Re: question about mass in GR - black holes "David (Kronos Prime) Fuller" <fuller.david@hotmail.com> - 2018-03-18 11:45 -0700
                Re: question about mass in GR - black holes "David (Kronos Prime) Fuller" <fuller.david@hotmail.com> - 2018-03-18 11:44 -0700
                Re: question about mass in GR - black holes alsor@interia.pl - 2018-03-18 11:46 -0700
              Re: question about mass in GR - black holes Python <python@python.invalid> - 2018-03-18 19:40 +0100
          Re: question about mass in GR - black holes Tom Roberts <tjroberts137@sbcglobal.net> - 2018-03-20 19:39 -0500
            Re: question about mass in GR - black holes alsor@interia.pl - 2018-03-21 10:26 -0700
              Re: question about mass in GR - black holes Tom Roberts <tjroberts137@sbcglobal.net> - 2018-03-21 19:13 -0500
                Re: question about mass in GR - black holes alsor@interia.pl - 2018-03-21 17:55 -0700
                Re: question about mass in GR - black holes Tom Roberts <tjroberts137@sbcglobal.net> - 2018-03-22 00:08 -0500
                Re: question about mass in GR - black holes mlwozniak@wp.pl - 2018-03-22 00:05 -0700
                Re: question about mass in GR - black holes alsor@interia.pl - 2018-03-22 14:06 -0700
                Re: question about mass in GR - black holes "David (Kronos Prime) Fuller" <fuller.david@hotmail.com> - 2018-03-22 14:37 -0700
                Re: question about mass in GR - black holes "David (Kronos Prime) Fuller" <fuller.david@hotmail.com> - 2018-03-21 18:09 -0700
                Re: question about mass in GR - black holes alsor@interia.pl - 2018-03-21 18:19 -0700
                Re: question about mass in GR - black holes "David (Kronos Prime) Fuller" <fuller.david@hotmail.com> - 2018-03-21 18:43 -0700
                Re: question about mass in GR - black holes "David (Kronos Prime) Fuller" <fuller.david@hotmail.com> - 2018-03-21 18:46 -0700
                Re: question about mass in GR - black holes alsor@interia.pl - 2018-03-21 20:22 -0700
                Re: question about mass in GR - black holes "David (Kronos Prime) Fuller" <fuller.david@hotmail.com> - 2018-03-21 20:55 -0700
                Re: question about mass in GR - black holes "David (Kronos Prime) Fuller" <fuller.david@hotmail.com> - 2018-03-21 21:11 -0700
                Re: question about mass in GR - black holes "David (Kronos Prime) Fuller" <fuller.david@hotmail.com> - 2018-03-21 21:21 -0700
                Re: question about mass in GR - black holes "David (Kronos Prime) Fuller" <fuller.david@hotmail.com> - 2018-03-21 21:26 -0700
                Re: question about mass in GR - black holes "David (Kronos Prime) Fuller" <fuller.david@hotmail.com> - 2018-03-21 20:49 -0700
  Re: question about mass in GR - black holes Keith Stein <keithstein111@gmail.com> - 2018-03-19 15:45 +0000
  Re: question about mass in GR - black holes numbernumber1964@gmail.com - 2018-03-20 13:51 -0700
    Re: question about mass in GR - black holes Odd Bodkin <bodkinodd@gmail.com> - 2018-03-20 23:02 +0000
  Re: question about mass in GR - black holes numbernumber1964@gmail.com - 2018-03-20 13:54 -0700
  Re: question about mass in GR - black holes Koobee Wublee <koobee.wublee@gmail.com> - 2018-03-21 10:40 -0700
    Re: question about mass in GR - black holes "David (Kronos Prime) Fuller" <fuller.david@hotmail.com> - 2018-03-21 11:17 -0700
    Re: question about mass in GR - black holes alsor@interia.pl - 2018-03-21 11:27 -0700
  Re: question about mass in GR - black holes numbernumber1964@gmail.com - 2018-03-22 15:26 -0700
    Re: question about mass in GR - black holes alsor@interia.pl - 2018-03-29 15:25 -0700

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