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Quasar found 13 billion years away



 
 
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  #81  
Old July 24th 07, 10:55 AM posted to sci.astro.research
Chalky
external usenet poster
 
Posts: 219
Default Quasar found 13 billion years away

On Jul 23, 8:30 am, (Phillip Helbig---
remove CLOTHES to reply) wrote:
In article , Chalky

writes:
On Jul 18, 10:30 am, (Phillip Helbig---
remove CLOTHES to reply) wrote:
In article , Chalky


writes:
Black holes radiate by Hawking radiation.


What is the Hawking temperature for a black hole of macho mass? (Yes, I
know,


You astonish me.


Wonders never cease! :-)

Please tell me both the mass of the macho,


I meant the mass range the various observational projects (MACHO, OGLE,
MOA etc) were/are sensitive to. This is roughly between a millionth of
a solar mass and a solar mass. A solar mass has a Hawking temperature
of about 60 nK. (Thus, it would absorb more energy from the CMB than it
emits, causing it to increase in mass and thus decrease in temperature.)
The temperature is inversely proportional to the mass. In fact, it is
one of the great formulae:

T = \frac{\hbar c^{3}}{(8\pi^GMk}


According to http://casa.colorado.edu/~ajsh/hawk.html,

kT = hbar g / (2 pi c) where g = G M / R^2 and k is Boltzmann's
constant.

This is more logical, since it gives increasing temperature (and
intensity) with increasing mass. According to you, this relationship
is inverted.

[Mod. note: I think you'll find that R is a function of M. Indeed, the
web page says

`Bigger black holes are colder and dimmer: the Hawking temperature
is inversely proportional to the mass'

-- mjh]

(for a Schwarzschild black hole) where T is the temperature, hbar is the
reduced Planck constant, c is the speed of light, G is the gravitational
constant, M is the mass and k is Boltzmann's constant.

Thus, even at the bottom of the "MACHO mass range", the temperature is
only about 60 mK, still much less than that of the CMB.


I think I will trust my intuition and http://casa.colorado.edu, thank
you.

Chalky
  #82  
Old July 24th 07, 01:29 PM posted to sci.astro.research
Chalky
external usenet poster
 
Posts: 219
Default Quasar found 13 billion years away

On Jul 24, 10:55 am, Chalky wrote:
This is more logical, since it gives increasing temperature (and
intensity) with increasing mass. According to you, this relationship
is inverted.

[Mod. note: I think you'll find that R is a function of M. Indeed, the
web page says

`Bigger black holes are colder and dimmer: the Hawking temperature
is inversely proportional to the mass'


Thanks for pointing this out. (That had escaped my attention.) I have
attermpted to emphasise several times within the current discussion
subject, that I am on something of a fishing expedition here, in an
area I do not completely understand. I am not, as Phillip claims,
attempting to present a completed thesis. If I were, I would stick to
the areas I do understand, and the areas where I have incontrovertible
evidence that this understanding predicts reality more accurately and
elegantly than established theory does. (And, to be perfectly honest,
if that were the case, I would not be presenting such a thesis here.)

Having said that, since I love to throw spanners into the works to see
what happens,
I would also like to respond speculatively thus:

If I am correct in concluding that EFE is not quite the full shilling,
as indicated by its prediction of singularities (a point first made by
Einstein), then its predictions are going to be progressively more
unreliable as one gets progressively closer to the singularity. In
this context, I would be tempted to argue that a more massive black
hole OR wormhole, would not necessarily have a larger radius.

Chalky


[Mod. note: quoted text trimmed. Please remember the speculativeness
criterion for s.a.r. in followups along these lines -- mjh]
  #83  
Old July 25th 07, 09:51 AM posted to sci.astro.research
Chalky
external usenet poster
 
Posts: 219
Default Quasar found 13 billion years away

On Jul 24, 10:55 am, Chalky wrote:
On Jul 23, 8:30 am, (Phillip Helbig---
remove CLOTHES to reply) wrote:





In article , Chalky


writes:
On Jul 18, 10:30 am, (Phillip Helbig---
remove CLOTHES to reply) wrote:
In article , Chalky


writes:
Black holes radiate by Hawking radiation.


What is the Hawking temperature for a black hole of macho mass? (Yes, I
know,


You astonish me.


Wonders never cease! :-)


Please tell me both the mass of the macho,


I meant the mass range the various observational projects (MACHO, OGLE,
MOA etc) were/are sensitive to. This is roughly between a millionth of
a solar mass and a solar mass. A solar mass has a Hawking temperature
of about 60 nK. (Thus, it would absorb more energy from the CMB than it
emits, causing it to increase in mass and thus decrease in temperature.)
The temperature is inversely proportional to the mass. In fact, it is
one of the great formulae:


T = \frac{\hbar c^{3}}{(8\pi^GMk}


According tohttp://casa.colorado.edu/~ajsh/hawk.html,

kT = hbar g / (2 pi c) where g = G M / R^2 and k is Boltzmann's
constant.

This is more logical, since it gives increasing temperature (and
intensity) with increasing mass. According to you, this relationship
is inverted.

[Mod. note: I think you'll find that R is a function of M. Indeed, the
web page says

`Bigger black holes are colder and dimmer: the Hawking temperature
is inversely proportional to the mass'


Actually, I still don't get this. Even classically, mass is
proportional to density times R cubed. Why are more massive black
holes less dense than less massive ones? And why is Hawking radiation
supposed to be stronger when gravity is weaker?

C
  #84  
Old July 25th 07, 09:53 AM posted to sci.astro.research
Chalky
external usenet poster
 
Posts: 219
Default Quasar found 13 billion years away

On Jul 23, 8:14 pm, (Phillip Helbig---
remove CLOTHES to reply) wrote:
In article , Chalky





writes:
On Jul 21, 10:25 pm, Chalky wrote:
On Jul 18, 10:30 am, (Phillip Helbig---
remove CLOTHES to reply) wrote:


In article , Chalky


writes:
Black holes radiate by Hawking radiation.


What is the Hawking temperature for a black hole of macho mass? (Yes, I
know,


You astonish me. Please tell me both the mass of the macho, and its
Hawking temperature, to save us all time.


And, while you are on this subject, please also enlighten us as to
your predicted nature of the MACHO, too.


Why? I haven't predicted any mass for MACHOs.

The point was that you suggested that MACHOs could provide enough
radiation through Hawking radiation to fill a hole in your theory.


No. I suggested that MACHOs might contribute to the CMB. As you should
know, MACHO candidates include neutron stars, brown dwarfs, and
unassociated planets, as well as black holes. The only reason for
mentioning Hawking radiation was that, in all other cases, the
mechanism for thermal radiation is obvious.

Now that we have successfully eliminated black hole MACHOs as a
significant contributor, you have the remaining task of explaining how
eg planetary MACHOs, whose surfaces could be close to thermal
equilibrium with the night sky, can fail to radiate heat accordingly.
To do this, you will, presumably, need to explain how their cores can
fail to be hotter than their surfaces, as is the case for the Earth.


Chalky
  #85  
Old July 25th 07, 09:54 AM posted to sci.astro.research
Chalky
external usenet poster
 
Posts: 219
Default Quasar found 13 billion years away

On Jul 24, 1:29 pm, Chalky wrote:

Having said that, since I love to throw spanners into the works to see
what happens,
I would also like to respond speculatively thus:

If I am correct in concluding that EFE is not quite the full shilling,
as indicated by its prediction of singularities (a point first made by
Einstein), then its predictions are going to be progressively more
unreliable as one gets progressively closer to the singularity. In
this context, I would be tempted to argue that a more massive black
hole OR wormhole, would not necessarily have a larger radius.


Actually, I would like to debunk that trivial suggestion myself. The
Schwarzchild radius formula actually looks pretty robust, since it is
the same in Newtonian physics too.

C
  #86  
Old July 25th 07, 10:25 PM posted to sci.astro.research
Phillip Helbig---remove CLOTHES to reply
external usenet poster
 
Posts: 198
Default Quasar found 13 billion years away

In article , Chalky
writes:

And, while you are on this subject, please also enlighten us as to
your predicted nature of the MACHO, too.


Why? I haven't predicted any mass for MACHOs.


Then how do you know their Hawking temperature?


I explicitly stated that I was referring to the mass range the various
observational programmes (I even named some names) were/are sensitive
to.
  #87  
Old July 25th 07, 10:27 PM posted to sci.astro.research
Phillip Helbig---remove CLOTHES to reply
external usenet poster
 
Posts: 198
Default Quasar found 13 billion years away

In article , Chalky
writes:

What is the Hawking temperature for a black hole of macho mass? (Yes, I
know,


You astonish me.


Wonders never cease! :-)

Please tell me both the mass of the macho,


I meant the mass range the various observational projects (MACHO, OGLE,
MOA etc) were/are sensitive to. This is roughly between a millionth of
a solar mass and a solar mass. A solar mass has a Hawking temperature
of about 60 nK. (Thus, it would absorb more energy from the CMB than it
emits, causing it to increase in mass and thus decrease in temperature.)
The temperature is inversely proportional to the mass. In fact, it is
one of the great formulae:

T = \frac{\hbar c^{3}}{(8\pi^GMk}


According to http://casa.colorado.edu/~ajsh/hawk.html,

kT = hbar g / (2 pi c) where g = G M / R^2 and k is Boltzmann's
constant.

This is more logical, since it gives increasing temperature (and
intensity) with increasing mass. According to you, this relationship
is inverted.

[Mod. note: I think you'll find that R is a function of M. Indeed, the
web page says

`Bigger black holes are colder and dimmer: the Hawking temperature
is inversely proportional to the mass'

-- mjh]

(for a Schwarzschild black hole) where T is the temperature, hbar is the
reduced Planck constant, c is the speed of light, G is the gravitational
constant, M is the mass and k is Boltzmann's constant.

Thus, even at the bottom of the "MACHO mass range", the temperature is
only about 60 mK, still much less than that of the CMB.


I think I will trust my intuition and http://casa.colorado.edu, thank
you.


As the moderator's note shows, it is clear where your intuition is
taking you.

I quote one of the most famous formulae in all of physics, and point out
that the temperature is inversely proportional to the mass. Your
intuition indicates the opposite and you prefer to go with that. Thus,
don't be surprised if people are taking you less and less seriously with
every post of yours they read. One can debate about how observations
are interpreted, about whether perhaps something has been overlooked
etc, but questioning formulae derived from first principles (note:
Stephen Hawking is a theorist, not an experimentalist) or, worse,
stating that they are wrong, is tantamount to leaving scientific
discussion altogether.
  #88  
Old July 26th 07, 08:27 AM posted to sci.astro.research
Chalky
external usenet poster
 
Posts: 219
Default Quasar found 13 billion years away

On Jul 25, 10:27 pm, (Phillip Helbig---
remove CLOTHES to reply) wrote:
In article , Chalky





writes:
What is the Hawking temperature for a black hole of macho mass? (Yes, I
know,


You astonish me.


Wonders never cease! :-)


Please tell me both the mass of the macho,


I meant the mass range the various observational projects (MACHO, OGLE,
MOA etc) were/are sensitive to. This is roughly between a millionth of
a solar mass and a solar mass. A solar mass has a Hawking temperature
of about 60 nK. (Thus, it would absorb more energy from the CMB than it
emits, causing it to increase in mass and thus decrease in temperature.)
The temperature is inversely proportional to the mass. In fact, it is
one of the great formulae:


T = \frac{\hbar c^{3}}{(8\pi^GMk}


According tohttp://casa.colorado.edu/~ajsh/hawk.html,


kT = hbar g / (2 pi c) where g = G M / R^2 and k is Boltzmann's
constant.


This is more logical, since it gives increasing temperature (and
intensity) with increasing mass. According to you, this relationship
is inverted.


[Mod. note: I think you'll find that R is a function of M. Indeed, the
web page says


`Bigger black holes are colder and dimmer: the Hawking temperature
is inversely proportional to the mass'


-- mjh]


(for a Schwarzschild black hole) where T is the temperature, hbar is the
reduced Planck constant, c is the speed of light, G is the gravitational
constant, M is the mass and k is Boltzmann's constant.


Thus, even at the bottom of the "MACHO mass range", the temperature is
only about 60 mK, still much less than that of the CMB.


I think I will trust my intuition andhttp://casa.colorado.edu, thank
you.


As the moderator's note shows, it is clear where your intuition is
taking you.

I quote one of the most famous formulae in all of physics, and point out
that the temperature is inversely proportional to the mass. Your
intuition indicates the opposite and you prefer to go with that. Thus,
don't be surprised if people are taking you less and less seriously with
every post of yours they read. One can debate about how observations
are interpreted, about whether perhaps something has been overlooked
etc, but questioning formulae derived from first principles (note:
Stephen Hawking is a theorist, not an experimentalist) or, worse,
stating that they are wrong, is tantamount to leaving scientific
discussion altogether.- Hide quoted text -


Two extremes:
1) Question nothing and swallow everything (AKA parrot learning).
2) Question everything, and build only on answers that make sense.

You will find it is scientists in the second category who come up with
the most revolutionary breakthroughs: Copernicus, Newton, and
Einstein, for example, and scientists in the first category who then
learn those findings parrot fashion, once they have become accepted by
the scientific community at large.

If you fell into the second category, you would have noticed that the
formula seemed counter-intuitive, and then worked out why, as I did:
the operative gravitational force is the tidal force near the
Schwartzchild radius, which is larger for smaller masses, because the
Schwartzchild radius is much smaller.

The fact that you did not explain this, but instead criticised me for
asking questions, suggests your affinities lie closer to the first
extreme.

Please note that my response of Jul 25, 9:53 am, confirms that I had
worked this out for myself, and, consequently, accepted the formula,
long before your posting of Jul 25, 10:27 pm, ridiculing me for
needing to know why the formula was as it was.

Please stick to the point, and respond to my posting of Jul 25, 9:53
am.

Chalky

[Mod. note: Again, can I remind participants that we are supposed to
be discussing the science, not each other -- mjh]
 




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