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question about mass in GR - black holes

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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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#451882 — question about mass in GR - black holes

What is mass of a black hole?

I have in mind the famous radius of a spherical mass:
rs = 2m, the Schwarzschild radius.

The radius is a distance or a mass?

For example:
for sun the radius is equal about: rs = 3km,
thus a mass of sun is 1.5 km, because rs = 2m, so m = rs/2 - yes?

Unfortunately in the relativity theory a distance is not invariant quantity,
but a mass is invariant in GR, so... there is great ambiguity in the theory:
radius of a mass is: rs = 2m

but if a distance is not invariant then the mass cannot be invariant too, because 2m is simply m doubled - no?

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#451972

alsor@interia.pl wrote:
^^^^^^^^^^^^^^^^
It is considered polite here to post using one’s real name (nicknames may be 
added).

> What is mass of a black hole?

Put simply, the sum of the masses within its event horizon.

> I have in mind the famous radius of a spherical mass:
> rs = 2m, the Schwarzschild radius.

This is only true in natural units where G = c = 1:

<https://en.wikipedia.org/wiki/Natural_units>

The actual equation is

  rₛ = 2 G M∕c²

    [Different from the SI definition, one usually writes “M” for the mass
     to indicate that it is large(r than another mass).  Compare Newton’s
     law of universal gravitation: F = G M m∕r².]

You could have easily found that out by yourself by reading, e.g., 
Wikipedia.
 
> The radius is a distance or a mass?

A distance, of course.
 
> For example:
> for sun the radius is equal about: rs = 3km,

(_the Sun_, or _Sol_)

The current radius of Sol is 695'500 km.  The _Schwarzschild_ radius of Sol 
is ca. 3 km:

  rₛ = 2 G × M☉/c² ≈ 2 G × 1.9 × 10³⁰ kg∕c² ≈ 2'953 m

<http://www.wolframalpha.com/input/?dataset=&i=2+G+%C3%97+(mass+of+Sol)%2Fc%C2%B2>

This means: If all of Sol’s matter and energy would be compressed into a 
sphere whose radius is ca. 3 km, it would become a black hole (BH).

> thus a mass of sun is 1.5 km, because rs = 2m, so m = rs/2 - yes?

No.
 
> Unfortunately in the relativity theory a distance is not invariant
> quantity,

It is not _Lorentz_-invariant.

> but a mass is invariant in GR,

Again, _Lorentz_-invariant.  The mass of a BH, for example, *can* change: 
matter can fall beyond a BH’s outer event horizon to increase the BH’s mass 
(and thus the Schwarzschild radius and event horizon radius), and a BH
can lose mass by emitting radiation (thus shrink and eventually 
“evaporate”).

> so... there is great ambiguity in the theory:

Not at all.  You are just oversimplifying.

> radius of a mass is: rs = 2m

No.

> but if a distance is not invariant then the mass cannot be invariant too,
> because 2m is simply m doubled - no?

No.


PointedEars
-- 
Q: What did the nuclear physicist order for lunch?  
A: Fission chips.

(from: WolframAlpha)

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#453023

W dniu czwartek, 8 marca 2018 18:02:46 UTC+1 użytkownik Thomas 'PointedEars' Lahn napisał:
> alsor@interia.pl wrote:
> ^^^^^^^^^^^^^^^^
> It is considered polite here to post using one’s real name (nicknames may be 
> added).
> 
> > What is mass of a black hole?
> 
> Put simply, the sum of the masses within its event horizon.
> 
> > I have in mind the famous radius of a spherical mass:
> > rs = 2m, the Schwarzschild radius.
> 
> This is only true in natural units where G = c = 1:
> 
> <https://en.wikipedia.org/wiki/Natural_units>
> 
> The actual equation is
> 
>   rₛ = 2 G M∕c²
> 
>     [Different from the SI definition, one usually writes “M” for the mass
>      to indicate that it is large(r than another mass).  Compare Newton’s
>      law of universal gravitation: F = G M m∕r².]
> 
> You could have easily found that out by yourself by reading, e.g., 
> Wikipedia.
>  
> > The radius is a distance or a mass?
> 
> A distance, of course.
>  
> > For example:
> > for sun the radius is equal about: rs = 3km,
> 
> (_the Sun_, or _Sol_)
> 
> The current radius of Sol is 695'500 km.  The _Schwarzschild_ radius of Sol 
> is ca. 3 km:
> 
>   rₛ = 2 G × M☉/c² ≈ 2 G × 1.9 × 10³⁰ kg∕c² ≈ 2'953 m
> 
> <http://www.wolframalpha.com/input/?dataset=&i=2+G+%C3%97+(mass+of+Sol)%2Fc%C2%B2>
> 
> This means: If all of Sol’s matter and energy would be compressed into a 
> sphere whose radius is ca. 3 km, it would become a black hole (BH).
> 
> > thus a mass of sun is 1.5 km, because rs = 2m, so m = rs/2 - yes?
> 
> No.
>  
> > Unfortunately in the relativity theory a distance is not invariant
> > quantity,
> 
> It is not _Lorentz_-invariant.
> 
> > but a mass is invariant in GR,
> 
> Again, _Lorentz_-invariant.  The mass of a BH, for example, *can* change: 
> matter can fall beyond a BH’s outer event horizon to increase the BH’s mass 
> (and thus the Schwarzschild radius and event horizon radius), and a BH
> can lose mass by emitting radiation (thus shrink and eventually 
> “evaporate”).
> 
> > so... there is great ambiguity in the theory:
> 
> Not at all.  You are just oversimplifying.
> 
> > radius of a mass is: rs = 2m
> 
> No.
> 
> > but if a distance is not invariant then the mass cannot be invariant too,
> > because 2m is simply m doubled - no?
> 
> No.


The so-called Schwarzschild's radius has been improvised at hot...
and by some strongly imbecilic mainstream students, I think.

One simple fact destroys completely this idiotic fantasy about the black holes:

a positron-electron annihilation in the gravitational condition!

E0 = mc^2 - that is the standard energy from annihilation of: m = 2m_e,

But in the gravity the energy is lowered to:
E = E0 sqrt(1-2M/r);

for r = 2M, the E = 0,
thus it's evident: E = mc^2 = 0 => m = 0

So, this means: mass of any matter decreases under gravity.
What is obvious in the GR's regimes.... it's just highly nonlinear model, where a mass is a variable, not fixed quantity!
......

Finally: what it is going on in the 'science' about these BH?

You just still made the one stupid error for hundred years:
you use still the Newtonian, thus invariant mass, in the GR equations, what is plainly wrong.

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#453115

alsor@interia.pl wrote:

> The so-called Schwarzschild's radius has been improvised at hot...

It is _not_ called “Schwarzschild's radius”.

“improvised at hot” does not mean anything (in English).

The _Schwarzschild_ radius is a consequence of how (very well) general 
relativity models gravity:

<https://en.wikipedia.org/wiki/Schwarzschild_metric>

> and by some strongly imbecilic mainstream students, I think.

Sadly, you still have no clue.
 
> One simple fact destroys completely this idiotic fantasy about the black
> holes:

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:

  <https://www.ligo.org/detections/GW170814/press-release/pr-english.pdf>

- We can observe cores of other galaxies emitting relativistic jets, caused
  only when matter is ripped apart, accelerated, and heated when falling
  towards by a supermassive black hole:

  <https://en.wikipedia.org/wiki/Astrophysical_jet#/media/File:M87_jet.jpg>
  <https://en.wikipedia.org/wiki/Supermassive_black_hole>

- All observations of the vicinity of the radio source Sagittarius A* in the
  center of the Milky Way (our own galaxy) correspond with the assumption
  that it is a supermassive black hole:

  <https://en.wikipedia.org/wiki/Sagittarius_A*>

- Not far into the future, we should be able to observe that black hole
  directly for the first time:

  <https://en.wikipedia.org/wiki/Event_Horizon_Telescope>

See also:

<https://en.wikipedia.org/wiki/Black_hole#Observational_evidence>
 
> a positron-electron annihilation in the gravitational condition!

Gravity is currently best modeled by *general* relativity.  Positron–
electron annihilation is currently best modeled by quantum electrodynamics, 
a *special*-relativistic quantum field theory.

A unified theory that would be required to describe this situation exactly 
(quantum gravity) is vastly more complex that you think (or could comprehend 
at your point in the learning curve).  Which is why so far, *nobody* has 
managed to come up with one that satisfies all observations.  Even Hawking 
only managed describe the evaporation of a black hole in the classical 
limit.

<https://en.wikipedia.org/wiki/Quantum_gravity>

> E0 = mc^2 - that is the standard energy from annihilation of: m = 2m_e,

E₀ is the _rest_ energy in the *center-of-momentum* frame.  The *total* 
energy of a particle is always

  E  = E₀ + Eₖ

and

  E² = m²c⁴ + p²c²

and for massive particles

  p = γ m v = m v∕√(1 − v²∕c²)

so for them,

  E = γ m c²

[so their magnitude of momentum p, and their total energy, increases *non-
linearly* with relative speed v:

<http://www.wolframalpha.com/input/?dataset=&i=plot+m+c%5E2%2Fsqrt(1+-+v%5E2%2Fc%5E2)+where+m+%3D+1,
+c+%3D+1,+v+%3D+0+to+1>]

When particles collide, their previous kinetic energies Eₖ = m c² (γ − 1) 
contributes to the collision energy, which is why we use particle 
*accelerators* to produce particles with comparably large masses, like Higgs 
bosons [m(H⁰) ≈ 125 GeV/c²].  For that, in the LHC the gluons of protons 
collide at close to the speed of light in vacuum relative to the center-of-
momentum frame (inside the detectors, e.g. the CMS).

<https://en.wikipedia.org/wiki/Higgs_boson>
<https://cds.cern.ch/record/2255762/files/CERN-Brochure-2017-002-Eng.pdf>
 
> But in the gravity the energy is lowered to:
> E = E0 sqrt(1-2M/r);

How did you get that idea?
 
> for r = 2M, the E = 0,

I suppose that you are referring to the Schwarzschild radius rₛ = 2 G M∕c², 
and that you use natural units where G = c = 1, because a radius is _not_ a 
mass.  Probably someone has told you this before.
  
> thus it's evident: E = mc^2 = 0 => m = 0

Your oversimplification has made you to claim nonsense again.  When will you 
start studying what you are talking about?

> So, this means: mass of any matter decreases under gravity. […]

Ex falso quodlibet.


PointedEars
-- 
A neutron walks into a bar and inquires how much a drink costs.
The bartender replies, "For you? No charge."

(from: WolframAlpha)

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#453118

Thomas 'PointedEars' Lahn wrote:

>> One simple fact destroys completely this idiotic fantasy about the
>> black holes:
> 
> 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:

The way you write indicates dementia.

*_P L O N K_*

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#453120

The ’nym-shifting troll trolled as "Darryl Fletcher" <lu@ewiwwe.tt>:
                                                         ^^^^^^^^^
> The way you write indicates dementia.
> 
> *_P L O N K_*

Hilarious.  *PLONK*

-- 
PointedEars

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#453128

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.

Simply:
for very extreme gravity the potential is near to the limit: -1/2 c^2;

thus any such body can bend the light around already, etc.

>   <https://www.ligo.org/detections/GW170814/press-release/pr-english.pdf>
> 
> - We can observe cores of other galaxies emitting relativistic jets, caused
>   only when matter is ripped apart, accelerated, and heated when falling
>   towards by a supermassive black hole:
> 
>   <https://en.wikipedia.org/wiki/Astrophysical_jet#/media/File:M87_jet.jpg>
>   <https://en.wikipedia.org/wiki/Supermassive_black_hole>
> 
> - All observations of the vicinity of the radio source Sagittarius A* in the
>   center of the Milky Way (our own galaxy) correspond with the assumption
>   that it is a supermassive black hole:
> 
>   <https://en.wikipedia.org/wiki/Sagittarius_A*>
> 
> - Not far into the future, we should be able to observe that black hole
>   directly for the first time:
> 
>   <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!

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!

 
> 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,
which immediately destroys yours fantasy about BH.

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.

[toc] | [prev] | [next] | [standalone]

#453159

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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#453175

W dniu niedziela, 18 marca 2018 21:02:31 UTC+1 użytkownik Thomas 'PointedEars' Lahn napisał:

> 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.

try to observe this:
1 = 0

can you see this?
Yes, therefore you just confirmed: 'one is zero', because you observed this directly.
  
> > 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*).

Potential has a dimension of speed squared: v^2.

v^2 = GM/r = -V.
mv^2/2 / m = v^2/2, it's a speed squared too, by 2.
...


> 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.
>
> 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).

Any atomic energy is reduced in this way - by the gravitational redshift.
Why?

Because any (atomic) energy is always: mc^2, what means it's proportional to a mass - of an atom!

for example the hydrogen's emission energy:

E = alpha^2 mc^2 x 1/ n^2 ...

Is this proportional to the atom's mass?
Of course is it.

All energies are redshifted there, because any mass is reduced in the gravity!

E = mc^2 = m0c^2 sqrt(1-2M/r) => m = m0 x sqrt(1-2M/r)

One simple example: two masses, say: a binary star.

The potential is: -m/r  - on both masses.

and the m is there the real mass, not newtonian one!
because of:

m = m0 sqrt(1-2m/r);

where:
m0 - is the oryginal mass (newtonian);
m - this is the real mass of a body, in the GR regime.

Solve this equation:
m = ?

.................

The mass m, in this: rs = 2m, has been simply assumed without any groud,
directly from the newtonian gravity:

for example it's an observed acceleration:
g(r) = -Gm/r^2 -> m = ...
then we can rediscovery the mass m, measuring r - distance.

ect.

But this is no more the Newtonian mass, unfortunately!
and because of that stupid fact you all have lost... in the dark of these black holes.

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#453179

alsor@interia.pl wrote:

> W dniu niedziela, 18 marca 2018 21:02:31 UTC+1 użytkownik Thomas
> 'PointedEars' Lahn napisał:
>> 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.
> 
> try to observe this:
> 1 = 0
> 
> can you see this?
> Yes, therefore you just confirmed: 'one is zero', because you observed
> this directly.

Ridiculous.
   
>> > 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*).
> 
> Potential has a dimension of speed squared: v^2.

For the *dimensions* of *gravitational* potential we are actually *both* 
correct because what I stated is actually not contrary, but equivalent to 
what you indicated:

  [U] = [G] × [m] [M]∕[R] = 1 m³∕(kg × s²) × kg²∕m = 1 kg m²∕s²

  [V] = [U]∕[m] = 1 kg m²∕(s² kg) = 1 m²∕s² = [length]²∕[time]² = [speed]²

<https://en.wikipedia.org/wiki/Gravitational_potential>

However, it is of course only that simple in *Newtonian* mechanics, which 
does not apply to black holes.
 
> Any atomic energy is reduced in this way - by the gravitational redshift.
> Why?
> 
> Because any (atomic) energy is always: mc^2, what means it's proportional 
> to a mass - of an atom!
> 
> [more nonsense]

Sadly, you are a hopeless case.


PointedEars
-- 
A neutron walks into a bar and inquires how much a drink costs.
The bartender replies, "For you? No charge."

(from: WolframAlpha)

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#453257

W dniu niedziela, 18 marca 2018 22:58:55 UTC+1 użytkownik Thomas 'PointedEars' Lahn napisał:

> > Any atomic energy is reduced in this way - by the gravitational redshift.
> > Why?
> > 
> > Because any (atomic) energy is always: mc^2, what means it's proportional 
> > to a mass - of an atom!
> > 
> > [more nonsense]
> 
> Sadly, you are a hopeless case.
 

What is a nonsense?
The gravitational redshift and the gravitational clocks slow-down effect?

The both are experimental facts, and provided in the GR also.

1. E = E0 sqrt(1+2V) =>

and because of that:
2. T = T0 / sqrt(1+2V); the slow-down effect (gravitational time dilation).

1 + 2 + mc^2 =>

3. m = m0 sqrt(1+2V);

Mass dependency on gravity!

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#453302

alsor@interia.pl wrote:

> W dniu niedziela, 18 marca 2018 22:58:55 UTC+1 użytkownik Thomas
> 'PointedEars' Lahn napisał:

Attribution line, not attribution novel.

>> > Any atomic energy is reduced in this way - by the gravitational
>> > redshift. Why?
>> > 
>> > Because any (atomic) energy is always: mc^2, what means it's
>> > proportional to a mass - of an atom!
>> > 
>> > [more nonsense]
>> 
>> Sadly, you are a hopeless case.
>  
> 
> What is a nonsense?
> The gravitational redshift and the gravitational clocks slow-down effect?

The latter is properly called “gravitational time dilation”.  Clocks DO NOT 
actually slow down (unless they are broken).  We have been over this
/ad nauseam/ here.
 
> The both are experimental facts, and provided in the GR also.

Both are NOT "provided in the GR also", but they are *consequences* of what 
GR has to say about the properties of spacetime.

Spouting pseudo-scientific word salad, because you actually have not the 
slightest clue about GR, you are missing the point.
 
> 1. E = E0 sqrt(1+2V) =>

That is such a nonsense, it is not even wrong.

Actually:

  E₀ = m c²

  E² = m²c⁴ + p²c²    (Energy–momentum relation)

   γ = 1∕√(1 – v²∕c²),

where

  E₀ – rest energy
  m  – mass of *moving* object
  c  – speed of light
  γ  – Lorentz factor
  v  – relative *speed* of *moving* object (*small* v)

For m ≠ 0,

   p = γ m v = m v∕√(1 – v²∕c²)

so

   E = γ m c² = γ E₀ = E₀∕√(1 − v²∕c²).

You claim:

  E' = E₀ √(1 + 2 V)

where

  V – *gravitational potential* (instead; it is a *capital* V):

      V(r⃗) = −G M∕r

      where

      G – Newtonian gravitational constant
      M – mass of *stationary* object
      r – distance from center of mass

It would follow:

  E' = E₀ √(1 + 2 V) = E₀ √(1 − 2 G M∕r)
 
Care to explain how to calculate that root?  The summands in the radicand do 
not even have the same dimensions.

In addition, the above energy–momentum relation is defined in *special* 
relativity only, where spacetime is *flat*.  In *general* relativity, energy 
(density) is a part of the energy–momentum tensor, so the relation is 
*vastly* more complex than you claim:

<https://link.springer.com/article/10.12942/lrr-2004-4>

Finally, you can NOT use concepts of *Newtonian* mechanics in *relativistic* 
context *without* making adjustments.  In particular, Newtonian mechanics 
*cannot* be used to describe any *curved* spacetime such as black holes.

> and because of that:
> 2. T = T0 / sqrt(1+2V); the slow-down effect (gravitational time
> dilation).

Nonsense.

Actually:

     T = T₀∕√(1 − 2 G M∕(r c²))

where

  T  – coordinate time interval
  T₀ – proper time interval
  G  – Newtonian gravitational constant
  M  – mass of source of gravitational field
  r  – radial coordinate of observer (distance from center of mass)
  c  – speed of light

You claim:

    T' = T₀∕√(1 + 2 V)

Actually:

  V(r⃗) = −G M∕r

It would follow:

    T' = T₀∕√(1 − 2 G M∕r) ≠ T.

Aside from the dimensions issue, you can NOT use natural units *and* simply 
ignore about the relations between and meanings of quantities because that 
is convenient.  That is NOT science, but *pseudo*-science.
 
> 1 + 2 + mc^2 =>
> 
> 3. m = m0 sqrt(1+2V);
> 
> Mass dependency on gravity!

Result: Utter nonsense.

You have it completely backwards.

Mass is a Lorentz-*invariant* quantity.

In GR, the definition of mass also is *vastly* more complex than you claim:

<https://en.wikipedia.org/wiki/Mass_in_general_relativity>


GR *actually* says:

The density of mass/energy (and momentum, and stress) in spacetime 
corresponds to the curvature of spacetime there.

Gravity is merely the observable effect of the curvature of spacetime.  It 
is observable as such only by *us* (humanoids), because we are not able to 
perceive the curvature of spacetime directly.

Objects in free fall always have trajectories that are described by the 
geodesics of spacetime.  When spacetime is locally curved, those geodesics 
are no longer straight lines.  So we observe phenomena described by *curved* 
lines, such as orbits, gravitational lensing, and black holes.

Put simply:

  “Spacetime tells matter how to move; matter tells spacetime how to curve.”
  
    —John A. Wheeler, “Geons, Black Holes, and Quantum Foam” (2000), p. 235

    [With “matter”, Wheeler is referring to particles with non-zero mass.¹]

<http://www.einstein-online.info/elementary/generalRT.html>

If you still do not understand it after watching this, you will probably 
never understand it:

<https://www.youtube.com/watch?v=0jjFjC30-4A>


My next rebuttal will not be as detailed as its necessity would prove that 
you do not *want* to learn.  You have been warned.


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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#453340

W dniu wtorek, 20 marca 2018 04:43:30 UTC+1 użytkownik Thomas 'PointedEars' Lahn 

> My next rebuttal will not be as detailed as its necessity would prove that 
> you do not *want* to learn.  You have been warned.

You are strongly uneducated... quite like my computer is. :)

So, go and learn more, babe, instead of promoting and reproducing here these series of compositions of symbols, which you don't recognise at all... my computer is still better than you in this domain. :)

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#453346

alsor@interia.pl wrote:

> W dniu wtorek, 20 marca 2018 04:43:30 UTC+1 użytkownik Thomas
> 'PointedEars' Lahn
>> My next rebuttal will not be as detailed as its necessity would prove
>> that you do not *want* to learn.  You have been warned.
> 
> You are strongly uneducated... quite like my computer is. :)
> 
> So, go and learn more, babe, instead of promoting and reproducing here
> these series of compositions of symbols, which you don't recognise at
> all... my computer is still better than you in this domain. :)

[sic!]

I notice, unsurprised, that you are unable to refute my refutations.

But I acknowledge that you are better at throwing mud than me.


PointedEars
-- 
Q: What happens when electrons lose their energy?  
A: They get Bohr'ed.

(from: WolframAlpha)

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#453358

W dniu wtorek, 20 marca 2018 21:03:16 UTC+1 użytkownik Thomas 'PointedEars' Lahn napisał:
> alsor@interia.pl wrote:
> 
> > W dniu wtorek, 20 marca 2018 04:43:30 UTC+1 użytkownik Thomas
> > 'PointedEars' Lahn
> >> My next rebuttal will not be as detailed as its necessity would prove
> >> that you do not *want* to learn.  You have been warned.
> > 
> > You are strongly uneducated... quite like my computer is. :)
> > 
> > So, go and learn more, babe, instead of promoting and reproducing here
> > these series of compositions of symbols, which you don't recognise at
> > all... my computer is still better than you in this domain. :)
> 
> [sic!]
> 
> I notice, unsurprised, that you are unable to refute my refutations.
> 
> But I acknowledge that you are better at throwing mud than me.
> 
> 
> PointedEars
> -- 
> Q: What happens when electrons lose their energy?  
> A: They get Bohr'ed.
> 
> (from: WolframAlpha)

You are simply useless in any sense, due to very little abilities.

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#453366

alsor@interia.pl wrote:

> W dniu wtorek, 20 marca 2018 21:03:16 UTC+1 użytkownik Thomas
> 'PointedEars' Lahn napisał:
>> I notice, unsurprised, that you are unable to refute my refutations.
>> 
>> But I acknowledge that you are better at throwing mud than me.
>> […]
> 
> You are simply useless in any sense, due to very little abilities.

Q.E.D.


F’up2 where it belongs

PointedEars
-- 
Q: Why is electricity so dangerous?  
A: It doesn't conduct itself.

(from: WolframAlpha)

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#452019

On 3/7/18 4:23 PM, alsor@interia.pl wrote:
> What is mass of a black hole?

Technically, primordial black holes don't have any mass, but they behave
as if they did. So for a Schwarzschild black hole, M is a parameter of
the hole that corresponds to the mass it behaves like. That is, the
black hole can form a binary system with some other mass, and as long as
the other object stays well outside the black hole's horizon, the system
behaves as if the black hole was an ordinary compact object with mass M.

Black holes formed by the collapse of matter have a mass equal to the
sum of everything that contributed to it.

> I have in mind the famous radius of a spherical mass: rs = 2m, the 
> Schwarzschild radius. The radius is a distance or a mass?

The radius is a distance, not a mass. But in "natural" units with c=G=1,
both mass and length use the same unit (e.g. cm).

In MKS units, rs = 2 G M / c^2 -- it's quite clear that rs and M
use different units when using MKS (rs is in meters and M is in kg).

	Ditto for length and time. In natural units they use the
	same unit, but in MKS they clearly use different units
	(meter and second).

Remember what a unit is: it is a standard interval to which all
measurements are referenced by taking the ratio of the measurement to
the interval corresponding to the unit. So a measurement result of 10
meters means the measured value is 10 times as long as the standard
meter. The system of natural units has just selected these standard
intervals not by history, but rather to make certain physical constants
have the value 1 -- there's NOTHING mysterious about this, it's just a
set of different choices for the standard intervals.

> For example: for sun the radius is equal about: rs = 3km, thus a
> mass of sun is 1.5 km, because rs = 2m, so m = rs/2 - yes?

No. Mass and length are quite different. It's just that in the system of
natural units they use the same unit.

> Unfortunately in the relativity theory a distance is not invariant 
> quantity, but a mass is invariant in GR, so... there is great 
> ambiguity in the theory: radius of a mass is: rs = 2m

Nope. You are confusing values with their units. Length and mass are
quite different, but in natural units they use the same unit (usually
cm). That is the standards for time and mass are chosen so c=G=1.

	When measuring a time interval to be "10 cm", do NOT think
	of cm as "1/100 the length of a meter", think of it as an
	ABSTRACT unit of time. When measuring a mass to be "1.5 km",
	do NOT think of km as some specific distance, think of it as
	an ABSTRACT unit of mass.

> but if a distance is not invariant then the mass cannot be invariant 
> too, because 2m is simply m doubled - no?

No. Mass is invariant and distance/length is not (but PROPER length is
invariant...). Mass and length are quite different, even though they use
the same unit in the system of natural units.

Tom Roberts

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#452030

On 3/8/18 5:43 PM, Tom Roberts wrote:
> No. Mass and length are quite different. It's just that in the system of
> natural units they use the same unit.

I could have said this better.

Mass and length are quite different. It's just that in the system of 
natural units they use units whose names are spelled the same.

That is: The length corresponding to 1 cm is quite different from the 
amount of mass corresponding to 1 cm, and both are quite different from 
the time interval corresponding to 1 cm.

Tom Roberts

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#452966

On 09/03/2018 01:51, Tom Roberts wrote:
> On 3/8/18 5:43 PM, Tom Roberts wrote:

>> No. Mass and length are quite different.

WELL, WELL, WELL !!!  WILL YOU LOOK AT THAT?
Here is something Tom Roberts and i agree on eh!


>> It's just that in the system of
>> natural units they use the same unit.
> 
> I could have said this better.
> 
> Mass and length are quite different. It's just that in the system of 
> natural units they use units whose names are spelled the same.

You are losing me again Mr.Roberts :(

> That is: The length corresponding to 1 cm is quite different from the 
> amount of mass corresponding to 1 cm, and both are quite different from 
> the time interval corresponding to 1 cm.

I think you said it much better the first time Mr.Roberts.

keith stein

> Tom Roberts

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#452039

On Friday, 9 March 2018 00:43:51 UTC+1, tjrob137  wrote:
> On 3/7/18 4:23 PM, alsor@interia.pl wrote:
> > What is mass of a black hole?
> 
> Technically, primordial black holes don't have any mass, but they behave
> as if they did. 

Tom, believe an engineer: your moronic mumble has nothing
in common with technic.

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