Speed of Light: A universal Constant?
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From: Henri Wilson on 15 Jun 2005 16:29 On Wed, 15 Jun 2005 12:28:04 +0000 (UTC), bz <bz+sp(a)ch100-5.chem.lsu.edu> wrote: >H@..(Henri Wilson) wrote in >news:0spua15326hoccjg7u2edghs9401ujgqj8(a)4ax.com: > >> 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: >>> >> >.... >>>> 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. > >But apparent angular velocity has NOTHING to do with anything useful. > >It only confuses what you might have been trying to say with something >totally unrelated. It invites an excursion down a dead end. Apparent >angular velocity is a dead end that we left behind when we abandoned the >model where the heavens rotated around a flat earth. >.... >> To somebody standing on Earth, it still APPEARS to move across the sky >> at about the same speed as the sun. Do you dispute that? > >Forget it! you are just making things worse! > >We are not concerned with those kinds of motion. They have nothing to do >with anything you want to use to support your assertions. > >We do not use apparent motion across the sky to determine relative velocity >of distant stars. I never even suggested that there we should. You should be careful. You will end up like Andersen if you keep this up. 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 16:32 On Wed, 15 Jun 2005 09:43:23 +0200, "Paul B. Andersen" <paul.b.andersen(a)deletethishia.no> wrote: >Henri Wilson wrote: >> On Tue, 14 Jun 2005 11:29:18 +0200, "Paul B. Andersen" >> <paul.b.andersen(a)deletethishia.no> wrote: >> >> >>>Henri Wilson wrote: >>> >>>>On Mon, 13 Jun 2005 10:29:05 +0200, "Paul B. Andersen" >>>><paul.b.andersen(a)deletethishia.no> wrote: >>>> >>>> >>>> >>>>>Henri Wilson wrote: >> >> >>>>That has been explained to you a thousand times. >>>> >>>>Now....... HoHoHohahahahaha! >>> >>>And what the explanation is that your program >>>doesn't work for real binaries where the orbital >>>parameters are measured? :-) >> >> >> It works perfectly. > >I see. >And the one time you tried to enter actual data >into your program it predicted that the binary HD80715 >should be a variable. >It isn't. That was explained 573 times to you. Now we have an exact fit with a RT Aur. What do you say about that? Incidentally, how many LYs in a parallex second? > >>>>Please compare the BaT predictions for RTAur with your reference: >>>> >>>>Just run my program again and see how it produces the exact characteristics of >>>>RT Aurigae. >>>> >>>>I have set the parameters to the right values. >>>>Run the distance to about 130-140 LYs. >>>>Then compare what you see with the reference you provided: >>>>http://mb-soft.com/public2/cepheid.html >>> >>>.. but you insist that your program does works for imaginary >>>binaries where you have invented the orbital parametres in >>>such a way that the the Cepheid is orbiting a star within itself? >>>Some program, eh? :-) >> >> >> You haev sasked me to show how the program predicts from actual figures. >> Just compare the predictions for RT Aur with the curves you provided. > >Indeed I have. >So what are the "actual data" for RT Aur you entered into your program? >How was those "actual data" measured? What is its distance from us? > >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: Paul B. Andersen on 15 Jun 2005 17:31 bz wrote: > H@..(Henri Wilson) wrote in > news:32rua1931htolan5pdbh8u6aa9piep8t8p(a)4ax.com: >>The paper is very confusing because the 'absolute' velocity curve is >>used. The BaT predictions are that the phase actually changes with >>distance. Initially the brightness peak leads the velocity peak. At >>greater distances it will catch up. I am presently looking into this >>because THe RT Aur curves are the first decent ones I have. I wish I >>could get a figure on distance for this star. So that you can tune the other "actual data" in your program to make it predict the observed light curve? :-) Because you have to observe the light curve before you can make your program "predict" it, right? :-) > You can compute the distance from the absolute brightness using the cepheid > formula. > > Paul said it is 1400 LY Yes. According to: http://www.astro.utoronto.ca/DDO/research/cepheids/table_physical.html the distance is 426 parsecs or 1389 LY. According to Hipparcos, the parallax is 2.09 mas, which means 470 parsecs or 1560 LY. But the uncertainty is in the order of 30%. This is however a very direct measurement, not dependent on any theory of how the star behaves. > You need to use the equation from that ppt presentation: > m_v-M_v = 5 log r -5, where r is the distance to the Cepheid, > m_v is the apparaent magnitude, M_v is the absolute magnitude. > > If I read the equation correctly, this implies that > distance = 10*exp(0.45051(m_v-M_v)) You do. A minor typo not worth meantioning: (so why do I do it?) ln(10)/5 = 0.46052, not 0.45051 But why the exp? Isn't r = 10*10^((m_v-M_v)/5) simpler? > When I use that formula, M_v of -3.036, m_v of 5.4 to 6.6 > I get distance of 486 to 845 (I assume parsecs) or 1587 to > 2758 Ly. Remember that M_v and m_v varies in exactly the same way. So you should use either the max, the mean, or the minimum values for both M_v and m_v. According to: http://www.astro.utoronto.ca/DDO/research/cepheids/table_physical.html The average values are M_v = -2.86 and m_v = 5.446 M_v is estimated from the luminosity-period relationship. According to the formula r = 458 parsecs, 1493 LY >>The graphs are still very confusing because the notes at the bottom >>claim that the maximum brightness occurs before the star has even >>reached half maximum size (36% of the cycle). Something doesn't quite >>add up here. > > > You have to bear in mind the mechanism. There is a change in transparency as > a layer heats up. As it gets bigger, it gets cooler and radiates less energy, > less brightness. > > That is why the brightness and size are not in phase. That's pretty much it. Look at: http://www.cosmovisions.com/cep01.htm It's in French, but the figures should be easy to understand. Temperature = Temperature Spectre = Spectrum (not ghost :-)) Vitesse radiale = Radial velocity (this curve is drawn "upside down") Rayon = radius Note that the maximum luminosity is when the temperature is highest. When the radius continues to increase, the temperature decreases, and since the power output per area is proportional to T^4, the luminosity decreases even if the surface area increases. And it is as you say the change in transparency that drives it, that is, transfer energy to the mechanical oscillator. Helium can be single or double ionized. He++ is more opaque than He+. When the star is hot, we have H++. Then the radiation pressure will make the star expand. It cools down because the increased surface area will make it radiate the energy faster. When the temperature decreases, the He++ ions will catch an electron, and be more transparent as He+. When the star is cool and small, it will radiate less energy than is produced in the core, it will heat up, and the cycle repeats. The reason why Cepheids are found only in a small part of the HR-diagram is that the star must have the right size and temperature so that the temperature varies around the critical temperature that ionizes He+ to He++ when the star pulsates. >>I am still working on it. I have redefined the yaw angle zero (rotated >>it 90 deg to conform and make life easier) so all my past figures are >>now out by 90. Be sure to include the spectrum and temperature. :-) Paul
From: bz on 15 Jun 2005 18:43 "Paul B. Andersen" <paul.b.andersen(a)deletethishia.no> wrote in news:d8q6nl$75d$1(a)dolly.uninett.no: > bz wrote: >> H@..(Henri Wilson) wrote in >> news:32rua1931htolan5pdbh8u6aa9piep8t8p(a)4ax.com: >>>The paper is very confusing because the 'absolute' velocity curve is >>>used. The BaT predictions are that the phase actually changes with >>>distance. Initially the brightness peak leads the velocity peak. At >>>greater distances it will catch up. I am presently looking into this >>>because THe RT Aur curves are the first decent ones I have. I wish I >>>could get a figure on distance for this star. > > So that you can tune the other "actual data" in your program > to make it predict the observed light curve? :-) > > Because you have to observe the light curve before > you can make your program "predict" it, right? :-) > >> You can compute the distance from the absolute brightness using the >> cepheid formula. >> >> Paul said it is 1400 LY > > Yes. > According to: > http://www.astro.utoronto.ca/DDO/research/cepheids/table_physical.html > the distance is 426 parsecs or 1389 LY. > > According to Hipparcos, the parallax is 2.09 mas, > which means 470 parsecs or 1560 LY. > But the uncertainty is in the order of 30%. > This is however a very direct measurement, not dependent on > any theory of how the star behaves. > >> You need to use the equation from that ppt presentation: >> m_v-M_v = 5 log r -5, where r is the distance to the Cepheid, >> m_v is the apparaent magnitude, M_v is the absolute magnitude. >> >> If I read the equation correctly, this implies that >> distance = 10*exp(0.45051(m_v-M_v)) > > You do. > A minor typo not worth meantioning: (so why do I do it?) It WAS worth mentioning! > ln(10)/5 = 0.46052, not 0.45051 You are right, I mistyped the number! > But why the exp? > Isn't r = 10*10^((m_v-M_v)/5) simpler? Yeah, but when I used mathcad to solve the equation, it stuck in the exponential and I didn't even stop to look at it carefully or think. >> When I use that formula, M_v of -3.036, m_v of 5.4 to 6.6 >> I get distance of 486 to 845 (I assume parsecs) or 1587 to >> 2758 Ly. > > Remember that M_v and m_v varies in exactly the same way. right. > So you should use either the max, the mean, or the minimum > values for both M_v and m_v. right. > According to: > http://www.astro.utoronto.ca/DDO/research/cepheids/table_physical.html > The average values are M_v = -2.86 and m_v = 5.446 > M_v is estimated from the luminosity-period relationship. > According to the formula r = 458 parsecs, 1493 LY right. >>>The graphs are still very confusing because the notes at the bottom >>>claim that the maximum brightness occurs before the star has even >>>reached half maximum size (36% of the cycle). Something doesn't quite >>>add up here. >> >> >> You have to bear in mind the mechanism. There is a change in >> transparency as a layer heats up. As it gets bigger, it gets cooler and >> radiates less energy, less brightness. >> >> That is why the brightness and size are not in phase. > > That's pretty much it. > Look at: > http://www.cosmovisions.com/cep01.htm > It's in French, but the figures should be easy to understand. > Temperature = Temperature > Spectre = Spectrum (not ghost :-)) > Vitesse radiale = Radial velocity > (this curve is drawn "upside down") > Rayon = radius > Note that the maximum luminosity is when the temperature is highest. > When the radius continues to increase, the temperature decreases, > and since the power output per area is proportional to T^4, > the luminosity decreases even if the surface area increases. > And it is as you say the change in transparency that drives it, > that is, transfer energy to the mechanical oscillator. > Helium can be single or double ionized. He++ is more opaque than He+. > When the star is hot, we have H++. Then the radiation pressure > will make the star expand. It cools down because the increased > surface area will make it radiate the energy faster. When > the temperature decreases, the He++ ions will catch an electron, > and be more transparent as He+. When the star is cool and small, > it will radiate less energy than is produced in the core, it will > heat up, and the cycle repeats. > > The reason why Cepheids are found only in a small part of > the HR-diagram is that the star must have the right size > and temperature so that the temperature varies around the critical > temperature that ionizes He+ to He++ when the star pulsates. Thanks! >>>I am still working on it. I have redefined the yaw angle zero (rotated >>>it 90 deg to conform and make life easier) so all my past figures are >>>now out by 90. > > Be sure to include the spectrum and temperature. :-) Henri needs to include 'sanity checking' in his program, to make sure the numbers are consistent. Currently, the program allows independent specification of values that are not independent. -- bz please pardon my infinite ignorance, the set-of-things-I-do-not-know is an infinite set. bz+sp(a)ch100-5.chem.lsu.edu remove ch100-5 to avoid spam trap
From: bz on 15 Jun 2005 20:07
H@..(Henri Wilson) wrote in news:lh21b15a2cffgj4b7uevuokgheoe506ete(a)4ax.com: > 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. Unless the relative motion of the pair is close to c, I think you are safe to neglect it. > 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 problem is that for any practicle size for the orgiting star(s), the orbital velocity will be MUCH higher than either 21 or 17 km/s to orbit in 5.36 days (much less the 3.7 days that RT Aur shows). >>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. Why do you say that? You ran the numbers and you came out with different numbers? You just don't like my numbers? Perhaps you don't believe the formula for orbital period? P=2 pi sqrt(a^3/(G*(M1+M2)) Which I solved for a getting a = 1/(2 pi) 2^(1/3) (P^2 G (M1+M2) pi)^(1/3) To get orbital velocity, I took the circumference over the period. You can approximate the perimiter(circumference for circle) as 2 pi sqrt((1/2)(a^2+b^2)) if you want. (less than 1% error for ecc < 0.40) I approximated it even more as (2 pi a) which works for small eccentricities. >>Obviously I have neglected to take into account the relativistic >>increase in mass of the star with velocity. > > There isn't any. That depends on ones model. I am afraid that even you will need to admit that it is difficult to get one star to orbit another at an orbital velocity > c. >>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. Until I can compare numbers to numbers, I can't be sure. > I have the proof, you are clutching at straws. Straws or telephone poles, it doesn't matter. The program currently is internally inconsistent and allows inconsistent parameters. >>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. Good! It has certainly been in need of such. > 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. Sometimes, I find it better to rewrite a program from scratch. Redesigning from the ground up allow me to eliminate a lot of problem. >>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. I think the problems are both simpler and deeper than that. >>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. Good. -- bz please pardon my infinite ignorance, the set-of-things-I-do-not-know is an infinite set. bz+nanae(a)ch100-5.chem.lsu.edu -- bz please pardon my infinite ignorance, the set-of-things-I-do-not-know is an infinite set. bz+sp(a)ch100-5.chem.lsu.edu remove ch100-5 to avoid spam trap |