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Black Hole Sound Waves



 
 
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  #21  
Old September 14th 03, 07:09 AM
Jeff Relf
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Hi Old Man ,
You say :
" The speed of sound in a gas of photons
( or of relativistic particles )
c_s ( photonic ) / c ( light )
= 1 / sqrt( 3 ) ~ 0.58
' Introduction to Cosmology ' B. Ryden "


Cosmology ? That figures .

Nothing blows my mind like cosmology does .
  #22  
Old September 14th 03, 07:09 AM
Jeff Relf
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Hi Old Man ,
You say :
" The speed of sound in a gas of photons
( or of relativistic particles )
c_s ( photonic ) / c ( light )
= 1 / sqrt( 3 ) ~ 0.58
' Introduction to Cosmology ' B. Ryden "


Cosmology ? That figures .

Nothing blows my mind like cosmology does .
  #23  
Old September 14th 03, 04:12 PM
Bill Sheppard
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A body of such density and extension
should be prone to vibrating, or ringing
for long periods of time, especially after
a large object has struck it.


Check out this 'clearinghouse' of info on BH ringdown-

http://astrogravs.gsfc.nasa.gov/docs...down_date.html

This could explain the observed
phenomenon of "black holes" producing
sound waves.


"Sound waves" in the near-perfect vacuum of space? Or acoustic pressure
waves in the fabric of space itself, propagating at c, otherwise known
as 'gravity waves'?

On a related note (no pun intended), here is an excellent piece
addressing the "speed of gravity" question-

http://www.metaresearch.org/cosmolog...of_gravity.asp

This paper also clarifies the distinction between gravity and 'gravity
waves'. The mainstream almost universally blurs the distinction,
creating the impression that gravity itself "propagates" from its
source, presumably at c.
As an analogy, picture the drain hole in a bathtub. While
draining, nothing "propagates" away from the hole. The medium itself
(water in this case) is flowing _into_ the hole. The inflow is fastest
at the hole. More distally from the hole, it is slower. But the flow is
still *toward* the hole; nothing's propagating 'away'. The
flowing-space model of gravity puts to rest the 'speed of gravity'
question.
oc

Anti-spam address: oldcoot88atwebtv.net
Change 'at' to@

  #24  
Old September 14th 03, 04:12 PM
Bill Sheppard
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Posts: n/a
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A body of such density and extension
should be prone to vibrating, or ringing
for long periods of time, especially after
a large object has struck it.


Check out this 'clearinghouse' of info on BH ringdown-

http://astrogravs.gsfc.nasa.gov/docs...down_date.html

This could explain the observed
phenomenon of "black holes" producing
sound waves.


"Sound waves" in the near-perfect vacuum of space? Or acoustic pressure
waves in the fabric of space itself, propagating at c, otherwise known
as 'gravity waves'?

On a related note (no pun intended), here is an excellent piece
addressing the "speed of gravity" question-

http://www.metaresearch.org/cosmolog...of_gravity.asp

This paper also clarifies the distinction between gravity and 'gravity
waves'. The mainstream almost universally blurs the distinction,
creating the impression that gravity itself "propagates" from its
source, presumably at c.
As an analogy, picture the drain hole in a bathtub. While
draining, nothing "propagates" away from the hole. The medium itself
(water in this case) is flowing _into_ the hole. The inflow is fastest
at the hole. More distally from the hole, it is slower. But the flow is
still *toward* the hole; nothing's propagating 'away'. The
flowing-space model of gravity puts to rest the 'speed of gravity'
question.
oc

Anti-spam address: oldcoot88atwebtv.net
Change 'at' to@

  #25  
Old September 14th 03, 04:25 PM
Uncle Al
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Jeff Relf wrote:
[snip]
Nothing.

A remote sparrow fart would blow your mind.


--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
"Quis custodiet ipsos custodes?" The Net!
  #26  
Old September 14th 03, 04:25 PM
Uncle Al
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Jeff Relf wrote:
[snip]
Nothing.

A remote sparrow fart would blow your mind.


--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
"Quis custodiet ipsos custodes?" The Net!
  #27  
Old September 14th 03, 08:39 PM
Jonathan Silverlight
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In message ,
Bill Sheppard writes
A body of such density and extension
should be prone to vibrating, or ringing
for long periods of time, especially after
a large object has struck it.


Check out this 'clearinghouse' of info on BH ringdown-

http://astrogravs.gsfc.nasa.gov/docs...down_date.html

This could explain the observed
phenomenon of "black holes" producing
sound waves.


"Sound waves" in the near-perfect vacuum of space? Or acoustic pressure
waves in the fabric of space itself, propagating at c, otherwise known
as 'gravity waves'?

On a related note (no pun intended), here is an excellent piece
addressing the "speed of gravity" question-

http://www.metaresearch.org/cosmolog...of_gravity.asp

This paper also clarifies the distinction between gravity and 'gravity
waves'. The mainstream almost universally blurs the distinction,
creating the impression that gravity itself "propagates" from its
source, presumably at c.


Corrections welcomed, but aren't _changes_ in gravitational fields
supposed to propagate by gravity waves? AFAIK the existence of gravity
waves has been fairly well confirmed by Taylor and Hulse's binary pulsar
observations, though everyone will be happier when direct observations
are made.
The speed of gravity is a lot more controversial, and I'm not sure it
can be measured. There seem to be a lot of people objecting to Ed
Fomalont and Sergei Kopeikin's measurement.
I know Tom van Flandern has some "interesting" views on this.
--
"Forty millions of miles it was from us, more than forty millions of miles of
void"
  #28  
Old September 14th 03, 08:39 PM
Jonathan Silverlight
external usenet poster
 
Posts: n/a
Default

In message ,
Bill Sheppard writes
A body of such density and extension
should be prone to vibrating, or ringing
for long periods of time, especially after
a large object has struck it.


Check out this 'clearinghouse' of info on BH ringdown-

http://astrogravs.gsfc.nasa.gov/docs...down_date.html

This could explain the observed
phenomenon of "black holes" producing
sound waves.


"Sound waves" in the near-perfect vacuum of space? Or acoustic pressure
waves in the fabric of space itself, propagating at c, otherwise known
as 'gravity waves'?

On a related note (no pun intended), here is an excellent piece
addressing the "speed of gravity" question-

http://www.metaresearch.org/cosmolog...of_gravity.asp

This paper also clarifies the distinction between gravity and 'gravity
waves'. The mainstream almost universally blurs the distinction,
creating the impression that gravity itself "propagates" from its
source, presumably at c.


Corrections welcomed, but aren't _changes_ in gravitational fields
supposed to propagate by gravity waves? AFAIK the existence of gravity
waves has been fairly well confirmed by Taylor and Hulse's binary pulsar
observations, though everyone will be happier when direct observations
are made.
The speed of gravity is a lot more controversial, and I'm not sure it
can be measured. There seem to be a lot of people objecting to Ed
Fomalont and Sergei Kopeikin's measurement.
I know Tom van Flandern has some "interesting" views on this.
--
"Forty millions of miles it was from us, more than forty millions of miles of
void"
  #29  
Old September 14th 03, 09:55 PM
Bill Sheppard
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Default

Jonathan S. asked,

...but aren't _changes_ in gravitational
fields supposed to propagate by gravity
waves?


Yes, oscillating masses (like co-orbiting neutron stars or binary BHs)
or massive gravitational events (like a SN going off) should radiate
copious amounts of GW energy. I prefer the term 'spatial acoustic
pressure waves' propagating at c. This clarifies the distinction between
gravity and so-called 'gravity waves'. But the latter term requires an
underlying spatial medium which is a big no-no.

AFAIK the existence of gravity waves
has been fairly well confirmed by Taylor
and Hulse's binary pulsar observations,
though everyone will be happier when
direct observations are made.


Yes, Taylor & Hulse's 1974 observations indirectly inferred the pulsar's
orbit was decaying by GW radiation as Einstein had predicted 'way back
in 1915. But this newest Chandra image is showing what appears be
*direct* signature of GWs. Yet they're being pawned off as "sound" in
the rarified gas of space, since space has gotta be 'pure void'. Uh-huh.
oc

Anti-spam address: oldcoot88atwebtv.net
Change 'at' to@

  #30  
Old September 14th 03, 09:55 PM
Bill Sheppard
external usenet poster
 
Posts: n/a
Default

Jonathan S. asked,

...but aren't _changes_ in gravitational
fields supposed to propagate by gravity
waves?


Yes, oscillating masses (like co-orbiting neutron stars or binary BHs)
or massive gravitational events (like a SN going off) should radiate
copious amounts of GW energy. I prefer the term 'spatial acoustic
pressure waves' propagating at c. This clarifies the distinction between
gravity and so-called 'gravity waves'. But the latter term requires an
underlying spatial medium which is a big no-no.

AFAIK the existence of gravity waves
has been fairly well confirmed by Taylor
and Hulse's binary pulsar observations,
though everyone will be happier when
direct observations are made.


Yes, Taylor & Hulse's 1974 observations indirectly inferred the pulsar's
orbit was decaying by GW radiation as Einstein had predicted 'way back
in 1915. But this newest Chandra image is showing what appears be
*direct* signature of GWs. Yet they're being pawned off as "sound" in
the rarified gas of space, since space has gotta be 'pure void'. Uh-huh.
oc

Anti-spam address: oldcoot88atwebtv.net
Change 'at' to@

 




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