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#21
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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
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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
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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
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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
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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
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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
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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
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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" |
#29
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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
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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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