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From: Henri Wilson on 15 Jun 2005 16:00 On Wed, 15 Jun 2005 05:10:41 -0400, David Evens <devens(a)technologist.com> wrote: >On Sun, 12 Jun 2005 21:00:03 GMT, The Ghost In The Machine ><ewill(a)sirius.athghost7038suus.net> wrote: > >>In sci.physics, Paul B. Andersen >><paul.b.andersen(a)deletethishia.no> >> wrote >>on Sun, 12 Jun 2005 21:33:22 +0200 >><d8i2m7$50d$1(a)dolly.uninett.no>: >>> The Ghost In The Machine wrote: >>>> In sci.physics, Paul B. Andersen >>>> <paul.b.andersen(a)deletethishia.no> >>>> wrote >>> >>>>>>On Thu, 09 Jun 2005 15:01:53 +0200, "Paul B. Andersen" >>>>>><paul.b.andersen(a)deletethishia.no> wrote: >>>>>> >>>>>>>A star is basically a spherical black body emitting >>>>>>>a black body spectrum. So the emitted power per surface >>>>>>>area is W = sigma*T^4, sigma = Stefan-Boltzmann constant. >>>>>>>When the temperature and emitted power is known, >>>>>>>the surface area and thus the diameter of the star can >>>>>>>be calculated. >>>> >>>> >>>> Assuming, of course, that a star is in fact a spherical >>>> thermal black body. (I'd say that's a fairly safe assumption, >>>> myself. :-) >>> >>> It will not be strictly spherical if it is rotating, >>> of course. >> >>Of course. But this is presumably a first-order approx... >> >>> >>>> However, I'd have to look at what photons are >>>> emitted from the H -> He reaction, and it may depend on >>>> which cycle the star uses.) >>> >>> The fusion emits gamma radiation. But that happens in >>> the core, and these photons do not go far before they are >>> absorbed. New photons are emitted - and absorbed. >>> It takes in the order of a million years for the energy >>> to get from the core to the surface of the star. >>> The star radiates its energy as a black body in >>> the photosphere. The temperature is what it has to be >>> to radiate as much energy as is produced in the fusion. >> >>There's also the issue of pressure -- which I'd not >>originally thought of applying to the problem. Crudely >>put, the star wants to contract to a point (or near point), >>whereas the fusion wants to explode. Things balance out >>just so, not unlike thermal equilibrium, though presumably >>harder to calculate. >> >>> >>> [..] >>> >>>>>So we have an invisible star with hundreds of solar masses. >>>>>Such stars do not exist. >>>> >>>> >>>> Black holes do. Admittedly, I for one would find a black >>>> hole nearly touching a glowing M1- or M2-mass star >>>> extremely unlikely without many highly noticeable effects, >>>> a la Cygnus X-1. >>>> >>>> I mention this mostly for completeness. >>> >>> Then think about this: >>> How could a 100 solar mass black hole be created? >>> When a black hole is created from a collapsing star, >>> its mass will be but few solar masses. >>> If such an animal exists, it certainly isn't as >>> a component of a binary. >>> (But who knows what may lurk in the centre of >>> some globular clusters?) >> >>Or for that matter at the center of galaxies? However, >>I think you're generally correct; if a 5 M_sun or so star >>is near a 100 M_sun or so black hole, it'll probably be >>ripped apart and eaten -- assuming that the black hole's >>creation explosion didn't simply disperse the gas of the >>companion star somehow in the first place. However, I'd >>have to look regarding said formation, and I know very >>little regarding the actual math beyond Chankdreksahr's >>Limit being about 1.5 M_sun. > >As was previously noted, you don't GET any stars that can colapse to >form a 100-solar mass black hole, because it is phsically impossible >for stars heavy enough to do so to form. The maximum mass for a star >is somewhere between 30 and 50 solar masses. It has been determined, >as well, that even the most massive stars blow off HUGE portions of >their matter when they collapse into black holes. A 30-solar mass >star, for instance, colapsing into a black hole blows off the >equivalent of an entire solar mass just as gamma rays. (This is what >we finally know to be the source of gamma ray bursts, and we can >consider ourselves fortunate to not have any such superheavy stars in >the immediate neighbourhood, since one of these going of with a few >tens kiloparsecs is a bad day for the homeworld.) All these figures are based on Einsteinina and are therefore to be taken with a grain of salt. I have discovered a new ttype of dark star, the Wilson,Cool,Heavy (WCH) Keep well away if you see one Evens. > >>Considering that Cepheids are extremely plentiful and >>relatively uniform they can't be created in too weird >>a fashion; Ockham's Razor would have a fit. :-) The most >>logical from my standpoint is that there's more gas >>than our Sun formed out of, and therefore we get a >>more massive single star. >> >>> >>> But anyway - as you say - a 100 solar masses black >>> hole in the close vicinity of a Cepheid would make >>> it presence very obvious. >> >>I should think so, not because of anything the black >>hole per se is doing, but because space gets so >>curved the gasses swirl into the hole and get very hot. >> >>> >>>>>And you think you by repeating "puffing and blowing" over and over >>>>>can make it ridiculous that a standing wave has a stable period? :-) >>>> >>>> >>>> Who says they have a constant period anyway? I suspect they slowly >>>> change -- *very* slowly, but I don't have the theory handy -- >>>> as the hydrogen is converted to helium and the density/characteristics >>>> of the star gas change. >>> >>> The period is NOT constant for eternity. Cepheids are stars which >>> have left the main sequence and passes through the instability >>> strip of the HR-diagram on their way to their death. >>> But we are talking about millions of years on this journey, >>> so most Cepheids will appear very regular for the century or >>> so we have observed (some of) them. >>> Polaris is an exception - the last century happens to be the >>> time when it leaves the instability strip. It is hardly >>> a Cepheid any more. >>> >>>> At some point a Cepheid will, quite literally, run out of gas. >>>> (Just like all the others, only different. :-) ) >>> >>> See: >>> http://www.astro.livjm.ac.uk/courses/one/NOTES/Garry%20Pilkington/loc.htm >> >>Interesting, and slightly weird. But then, the Universe is >>normal; *we* are the weird ones (postulating at one point, >>for example, that the Sun orbited around the Earth and >>was carried by a chariot). >> >>> Specifically the animated figure showing a star's journey >>> from the main sequence to its death - passing through >>> the instability strip twice - and thus being a Cepheid twice. >>> >>> >>>>>The Cepheid RT Aurigae with period 3.72 days, have a maxum >>>>>surface velocity 17 km/s. The escape velocity is 200 km/s. >>>>>So why would there be "bits of gas flying everywhere"? :-) >>>> >>>> >>>> Well, there would be moving bits of gas, anyway. I'll admit to >>>> wondering whether we can detect the movement with a sufficiently >>>> sensitive spectroscope. >>> >>> Indeed we can. It is routine. >> >>Somehow, that doesn't surprise me. My ignorance is considerable >>here, but it is nothing compared to someone else's... :-) >> >>> The pulsation is measured as a periodic variation in >>> the radial velocity of the star. >>> How did you think the surface velocity of RT Aurigae >>> cited above was measured? >>> http://mb-soft.com/public2/cepheid.html >> >>I'm not that familiar with spectroscopy so can't say of my own accord, >>but looks straightforward enough. >> >>> >>> Paul HW. www.users.bigpond.com/hewn/index.htm Sometimes I feel like a complete failure. The most useful thing I have ever done is prove Einstein wrong.
From: Henri Wilson on 15 Jun 2005 16:03 On Wed, 15 Jun 2005 05:12:11 -0400, David Evens <devens(a)technologist.com> wrote: >On Mon, 13 Jun 2005 00:26:23 GMT, H@..(Henri Wilson) wrote: >>On Sun, 12 Jun 2005 21:33:22 +0200, "Paul B. Andersen" >><paul.b.andersen(a)deletethishia.no> wrote: >>>The Ghost In The Machine wrote: >>>> In sci.physics, Paul B. Andersen >>>> <paul.b.andersen(a)deletethishia.no> >>>> wrote >>>>>>On Thu, 09 Jun 2005 15:01:53 +0200, "Paul B. Andersen" >>>>>><paul.b.andersen(a)deletethishia.no> wrote: >>>>>> >>>>>>>A star is basically a spherical black body emitting >>>>>>>a black body spectrum. So the emitted power per surface >>>>>>>area is W = sigma*T^4, sigma = Stefan-Boltzmann constant. >>>>>>>When the temperature and emitted power is known, >>>>>>>the surface area and thus the diameter of the star can >>>>>>>be calculated. >>>> >>>> >>>> Assuming, of course, that a star is in fact a spherical >>>> thermal black body. (I'd say that's a fairly safe assumption, >>>> myself. :-) >>> >>>It will not be strictly spherical if it is rotating, >>>of course. >>> >>>> However, I'd have to look at what photons are >>>> emitted from the H -> He reaction, and it may depend on >>>> which cycle the star uses.) >>> >>>The fusion emits gamma radiation. But that happens in >>>the core, and these photons do not go far before they are >>>absorbed. New photons are emitted - and absorbed. >>>It takes in the order of a million years for the energy >>>to get from the core to the surface of the star. >>>The star radiates its energy as a black body in >>>the photosphere. The temperature is what it has to be >>>to radiate as much energy as is produced in the fusion. >>> >>>[..] >>> >>>>>So we have an invisible star with hundreds of solar masses. >>>>>Such stars do not exist. >>>> >>>> >>>> Black holes do. Admittedly, I for one would find a black >>>> hole nearly touching a glowing M1- or M2-mass star >>>> extremely unlikely without many highly noticeable effects, >>>> a la Cygnus X-1. >>>> >>>> I mention this mostly for completeness. >>> >>>Then think about this: >>>How could a 100 solar mass black hole be created? >>>When a black hole is created from a collapsing star, >>>its mass will be but few solar masses. >>>If such an animal exists, it certainly isn't as >>>a component of a binary. >>>(But who knows what may lurk in the centre of >>> some globular clusters?) >>> >>>But anyway - as you say - a 100 solar masses black >>>hole in the close vicinity of a Cepheid would make >>>it presence very obvious. >> >>Hahahahah! >> >>What do you think causes the brightness curve to be exactly as the BaT predicts >>for a large star orbiting a neutron star or WCH? > >Not the BaT, since it ignores the effect such a massive body would >have on the gases being emitted from the visible star and the >radiation that would be released as these gasses were, inevitably, >trapped by its more massive companion. Evens don't come in here swinging!!! I already informed Paul that this was likely to happen and the stars were really a lot hotter and smaller than they appeared. The whole spectrum would be considerably redshifted. > >>>>>And you think you by repeating "puffing and blowing" over and over >>>>>can make it ridiculous that a standing wave has a stable period? :-) >>>> >>>> >>>> Who says they have a constant period anyway? I suspect they slowly >>>> change -- *very* slowly, but I don't have the theory handy -- >>>> as the hydrogen is converted to helium and the density/characteristics >>>> of the star gas change. >>> >>>The period is NOT constant for eternity. Cepheids are stars which >>>have left the main sequence and passes through the instability >>>strip of the HR-diagram on their way to their death. >>>But we are talking about millions of years on this journey, >>>so most Cepheids will appear very regular for the century or >>>so we have observed (some of) them. >>>Polaris is an exception - the last century happens to be the >>>time when it leaves the instability strip. It is hardly >>>a Cepheid any more. >>> >>>> At some point a Cepheid will, quite literally, run out of gas. >>>> (Just like all the others, only different. :-) ) >>> >>>See: >>>http://www.astro.livjm.ac.uk/courses/one/NOTES/Garry%20Pilkington/loc.htm >>>Specifically the animated figure showing a star's journey >>>from the main sequence to its death - passing through >>>the instability strip twice - and thus being a Cepheid twice. >>> >>> >>>>>The Cepheid RT Aurigae with period 3.72 days, have a maxum >>>>>surface velocity 17 km/s. The escape velocity is 200 km/s. >>>>>So why would there be "bits of gas flying everywhere"? :-) >>>> >>>> >>>> Well, there would be moving bits of gas, anyway. I'll admit to >>>> wondering whether we can detect the movement with a sufficiently >>>> sensitive spectroscope. >>> >>>Indeed we can. It is routine. >>>The pulsation is measured as a periodic variation in >>>the radial velocity of the star. >>>How did you think the surface velocity of RT Aurigae >>>cited above was measured? >>>http://mb-soft.com/public2/cepheid.html >> >>Paul, have you ever sen a radial velocity curve from a star in elliptical >>orbit, with ecc~ 1.5-4 and the the right yaw angle to create brigthtnees curves >>according to BaT principles? >> >>> >>>Paul >> >> >>HW. >>www.users.bigpond.com/hewn/index.htm >> >>Sometimes I feel like a complete failure. >>The most useful thing I have ever done is prove Einstein wrong. HW. www.users.bigpond.com/hewn/index.htm Sometimes I feel like a complete failure. The most useful thing I have ever done is prove Einstein wrong.
From: Henri Wilson on 15 Jun 2005 16:20 On Wed, 15 Jun 2005 13:15:18 +0000 (UTC), bz <bz+sp(a)ch100-5.chem.lsu.edu> wrote: >H@..(Henri Wilson) wrote in >news:1equa11h11huqcdprcjmqbii6peeg00tg5(a)4ax.com: > >>>> And this obviously explains how the 40 solar diameter delta Cep >>>> and a star which hasn't got to be a neutron star at all, >>>> can orbit their barycentre in the common period five days. >>>>>Delta Cep: >>>>>period = 5.366270 days >>>>>radius = 41.6 solar radii >>>>>mass = 5 solar masses > >By the way, the above values are for delta Cep, NOT RT Aur. > >>> >>>two stars of 5 solar masses would orbit at 1.9e7 km >>>41.6 solar radii is 2.8e7 km, which, as you have noted, is larger in >>>than the orbital radius. So the stars would merge. >>> >>>In fact, in order for one to skim the surface (assuming zero radius for >>>it), it would have to have a mass of 5.72 times the mass of delta Cep: >>> >>>This gives an orbital velocity of 268 km/s or 1.3e-3c >>> >>>I figure you need a very heavy black hole of at least 50 times the mass >>>of Delta Cep. That gives a separation of 1.96 radii, orbital velocity of >>>771 km/s or 2.5e-3 c >>> >>>All of these present a small problem, however, as the actual doppler >>>data figures for RT Aurigae show a maximum velocity of 38 km/sec. At 38 >>>km/sec, there is no way for the two stars to maintain orbit and they >>>will fall into each other. >> >> That velocity figure is confusing. The RT Aur system is moving away from >> Earth at 21 kms/sec..so you must subtract that. >> >> The maximum radial speed is only 17km/s. > >That just makes the orbiting stars model more impossible. > >But the max radial speed away from us (minimum) gets larger, so we should see >more subluminal photons than super luminal photons. Yes. I originally included in my program provision for the movement of the binary pair wrt Earth, but removed it because it doesn't affect the curve shapes, only the critical distances. This star is considered to be moving away very rapidly, however we cannot even be certain of that figure. > > >> >>> >>>That will make a big splash and, I fear, swamp Henri's model. >> >> There is known to be a lot of dark matter in the universe. >> Apparently, much of it has cepheids orbiting around. > >Henri, there is NO possible mass that a cepheid could be orbiting in 5.36 >days and have a radial velocity of only 21 kms/sec. For RT Aur, it is 17 km/s > >The larger the mass, the greater the orbit's diameter AND the greater the >orbital velocity. When M2 is 3e9 times M1, the orbital velocity reaches c. >With an orbital diameter of 1.5e10 km. You have something wrong there. > >Obviously I have neglected to take into account the relativistic increase in >mass of the star with velocity. There isn't any. > >While working through some of these formula it became apparent to me that >your program lacks a very important feature: A 'sanity check'. Keep on fighting. But you cannot deny it produces exactly the curves of RT Aur. I have the proof, you are clutching at straws. > >The program needs to flag inconsistent values. > >The orbital velocity, the orbit's diameter, and the mass(es) of the bodies >involved, can NOT all be independent. > >Your program appears to assume that they are. I am sure there are other sets >of interdependent parameters that likewise need to be cross checked. I am presently remodelling the program so it is easier to check and follow. In the RT Aur paper, the note "the brightness maximum occurs at a phase 130 degrees before the maximum size of the star" agrees well with my curves. I am redefining the Yaw angles so some parts of the program will appear to disagree with others in this respect until I unify it all. > >This means that one can currently put in values for interdependent parameters >that are inconsistent with each other. > >This explains some of the weird looking curves your program produces. All curves beyoind the critical distance will appear weird. The is a reason for that. You must increse the number of ornits until there is a flat section in the middle of the curves. > >When the user inputs two of the values, the program needs to calculate the >third and if that doesn't match what the user is specifying, the program >should flag the values to let the user know that they conflict with each >other. Like I said, the program is being improved. HW. www.users.bigpond.com/hewn/index.htm Sometimes I feel like a complete failure. The most useful thing I have ever done is prove Einstein wrong.
From: Henri Wilson on 15 Jun 2005 16:22 On Wed, 15 Jun 2005 10:26:05 +0200, "Paul B. Andersen" <paul.b.andersen(a)deletethishia.no> wrote: >Henri Wilson wrote: >> On Tue, 14 Jun 2005 14:38:28 +0200, "Paul B. Andersen" >> <paul.b.andersen(a)deletethishia.no> wrote: >> >> >>>Henri Wilson wrote: >>> >>>>On Mon, 13 Jun 2005 08:47:29 +0000 (UTC), bz <bz+sp(a)ch100-5.chem.lsu.edu> >>>>wrote: >>>> >>>> >>>> >>>>>H@..(Henri Wilson) wrote in >>>>>news:jtkpa1hu4tuk4ik1dtp62t42ro69d82jde(a)4ax.com: >>>>> >>>>> >>>>> >>>>>>Paul, Earth is about 100 solar diameters from the sun. >>>>>> >>>>>>The sun 'orbits the Earth' in one day. >>>>> >>>>>??? >>>>> >>>>>The earth rotates on its axis in one day. The sun does NOT orbit the earth >>>>>any more than the entire universe orbits the earth every 24 hours. >>>> >>>> >>>>Bob, Did you notice the ' ' ? >>>> >>>>I was merely trying to provide a visual impression of an object orbiting >>>>another once per day. A large object orbiting every five days, eg D Cep, would >>>>move a lot slower than that. >>>> >>>>The sun orbits the Earth/sun barycentre once per year. It also orbits the >>>>Jupiter/sun barycentre once per Jupiter year. >>>> >>>>If the sun had a large close companion, the two would orbit the barycentre at >>>>the common period. >>> >>>Quite. >>>And this obviously explains how the 40 solar diameter delta Cep >>>and a star which hasn't got to be a neutron star at all, >>>can orbit their barycentre in the common period five days. >> >> >> The other star is some kind of WCH....just like the one near RT Aur. > >So when you said: >| Paul, Earth is about 100 solar diameters from the sun. >| >| The sun 'orbits the Earth' in one day. >| Something 40 times bigger orbiting every five days would not appear to move >| very quickly, as seen by an observer on Earth. >| If Jupiter was even five times larger, it would cause the sun, no matter how >| big it might become to orbit around the barycentre at quite a large radius. >| >| D Cep doesn't need a neutron star as its companion, at all. > >You didn't mean to point out that Delta Cep doesn't need >a very massive star as its companion, at all? :-) > >That IS clear from the context, isn't it? :-) > >Paul this message is merely intended to procrastinate and confuse and therefore doesn't warrant a reply. HW. www.users.bigpond.com/hewn/index.htm Sometimes I feel like a complete failure. The most useful thing I have ever done is prove Einstein wrong.
From: Henri Wilson on 15 Jun 2005 16:27
On Wed, 15 Jun 2005 10:14:14 +0200, "Paul B. Andersen" <paul.b.andersen(a)deletethishia.no> wrote: >Henri Wilson wrote: >> On Tue, 14 Jun 2005 08:53:16 +0000 (UTC), bz <bz+sp(a)ch100-5.chem.lsu.edu> >> wrote: >> >> >>>H@..(Henri Wilson) wrote in >>>news:p1fsa1pt24bmi2c83ha9t314o9pm1snhdf(a)4ax.com: >>> >> >> >>>>>>>>Paul, Earth is about 100 solar diameters from the sun. >>>>>>>> >>>>>>>>The sun 'orbits the Earth' in one day. >>>>>>> >>>>>>>??? >>>>>>> >>>>>>>The earth rotates on its axis in one day. The sun does NOT orbit the >>>>>>>earth any more than the entire universe orbits the earth every 24 >>>>>>>hours. >>>>>> >>>>>>Bob, Did you notice the ' ' ? >>>>> >>>>>I did, but you were talking about a star orbiting in 5 days, implying >>>>>that was possible because the sun orbited the earth in 24 hours. >>>>> >>>>> >>>>>>I was merely trying to provide a visual impression of an object >>>>>>orbiting another once per day. A large object orbiting every five >>>>>>days, eg D Cep, would move a lot slower than that. >>>>> >>>>>Your image failed because to orbit in 24 hours, the sun would have had >>>>>to be in synchronous orbit altitude at 22,235 miles. Which would kinds >>>>>scorce my grass. >>>> >>>>Orbit diameter depends on the mass of the other object. >>>> >>>>Bob, my only concern was the apparent rate of movement, the angular >>>>velocity of something in a 1 day orbit. The sun doesn't appear to move >>>>very fast. >>> >>>The apparant angular velocity due to OUR rotation can not be counted. A 24 >>>hour orbit will be at a radius of 22,235 miles. >>> >>>http://en.wikipedia.org/wiki/Orbital_period >>>The orbital period depends on the masses involved, the semi major axis, and >>>the universal constant G. >>>P=2 pi sqrt(a^3/(G(M1+M2))) >>> >>>solving for 'a' gives >>>a=1/(2 pi) 2^(1/3) (P^2 G(M1+M2) pi)^(1/3) >>> >>>With the mass of the sun as 1.9891E+30*kg and the mass of the earth >>>5.9742E+24*kg, a 24 hour orbit is at 2.928E+6*km and the diameter of the >>>sun is 1.392E+6*km, so it would be theoretically possible for the earth to >>>orbit the sun in 24 hours. It would need to move at 213 km/s (7.1E-4 c) >>>(assuming a circular orbit) in order to do so >>> >>>But two stars the mass of the sun would have to orbit each other at 3.6E6 >>>KM at 268 km/s (8.9e-4 c). >> >> >> Look Bob, I am genuinely sorry for causing this confusion. I thought you had >> more brains that Andersen. >> >> I was merely pointing out that ANYTHING orbiting YOU once per day would appear >> to move at the same angular velocity as our sun (or moon) does as it APPEARS TO >> 'orbit' us. This was purely to illustrate the visual impression and had nothing >> to do with the maths of different sized objects. > >It's always entertaining to see Henri trying to >explain why his giant blunders are no blunders. :-) > >The context is that I pointed out the fact that if >a mass with zero diameter was orbiting delta Cep, >skimming its surface, the mass had to be 28 solar masses. > >To refute this fact, Henry wrote: >| Paul, Earth is about 100 solar diameters from the sun. >| >| The sun 'orbits the Earth' in one day. >| Something 40 times bigger orbiting every five days would not appear to move >| very quickly, as seen by an observer on Earth. >| If Jupiter was even five times larger, it would cause the sun, no matter how >| big it might become to orbit around the barycentre at quite a large radius. >| >| D Cep doesn't need a neutron star as its companion, at all. > >Note the conclusion. >The star Delta Cep is orbiting doesn't have to be very massive at all. > >Henry will of course now claim that when he said that D Cep >didn't need to orbit a neutron star, he didn't mean that >the star didn't have to be very massive, but that it can be >another kind of very heavy massive - like a dark matter star. > >Because he will never admit that he made the blunder everybody >can see that he did. > >Will you Henri? :-) > >Paul, enjoing the show Paul, as the idiot Evens just pointed out, all the light leaving the system is heavily redshifted by the large mass present. The plain fact is, D Cep and the like are much hotter and smaller than Einsteiniana has led astrophysicists to believe. HW. www.users.bigpond.com/hewn/index.htm Sometimes I feel like a complete failure. The most useful thing I have ever done is prove Einstein wrong. |