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#81
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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
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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
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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
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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
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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
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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
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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
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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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