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Why are the 'Fixed Stars' so FIXED?



 
 
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  #461  
Old March 16th 07, 09:38 PM posted to sci.physics.relativity,sci.astro
Henri Wilson
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Posts: 1,378
Default Why are the 'Fixed Stars' so FIXED?

On Fri, 16 Mar 2007 16:59:26 -0000, "George Dishman"
wrote:


"Henri Wilson" HW@.... wrote in message
.. .
On Fri, 16 Mar 2007 00:22:44 -0000, "George Dishman"


You can't do that, it's an unstable configuration. You
could get away with one at a Lagrange point but there
is a limit on the mass ratios.


I wasn't suggesting that an object was in orbit 90 out. As far as we know
that
is indeed impossible.


Fine, so you are not allowed to put one into your simulation
and claim you have succeeded. In fact you told me you got
the motion of the stars by simulating Newtonian gravity so
your configuration should have been unstable. It looks as
though that part is buggy too.

...but there could be other reasons...tidal effects(?)


Then simulate tidal effects. All you can do for now is use
two stars and get the best fit. If the residuals are within
the observational uncertainty you have a match and if not
you don't.

The fact that it was 90 and not 80 or 100 made me wonder.


Pointless since it cannot exist.


Then forget it. It was only a minor refinement anyway. The curve matched quite
well without it. I doubt if the published one is particularly accurate.

I was wondering about the material that is falling into the neutron star.
If it is spinning, its speed would drop of with distance. If it wasn't
spinning
the pulsar would be slowing down.


So look up the rate of change of the pulsar frequency, it is
one of the key published values.

Of course, you can create any possible shape with sufficient
harmonics but Keplerian orbits produce limits, that is the
anture of the test. You can't just add more factors.

Everything I add is strictly in accordance with the BaTh. I cannot
simply add
any old curve to produce the one I want. There are strict limitations
particularly for elliptical orbits.

Yes, and a third object is not allowed !


Of course it is....many star curves clearly involve a third or more
object.


Then those curves will almost certainly be failures too, you
cannot have a stable configuration with a third object except
under _very_ limited conditions (e.g. figure of eight or the
very disparate separations like the Sirius system).


George, does Jupiter have moons and orbit the sun?
Does the Earth have a moon George and orbit the sun?

I don't think you have fully realised the complexity of this whole issue
George.


I don't think you realise the constraints Keplerian orbits
place on you Henry.


George, there are probably 10 billion stars in our galaxy, most with companions
and orbiting planets.
Do you really think we know every possible configuration just by investigating
our own solar system?

However my program IS strictly limited to Keplerian orbits. I introduced the
phase variation to investigate Lagrange points....and found evidence that
objects DO exist at the 60 degree one.


George



"When a true genius appears in the world, you may know
him by this sign, that the dunces are all in confederacy against him."
--Jonathan Swift.
  #462  
Old March 16th 07, 09:39 PM posted to sci.physics.relativity,sci.astro
Henri Wilson
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Posts: 1,378
Default Why are the 'Fixed Stars' so FIXED?

On 16 Mar 2007 03:07:27 -0700, "Jerry" wrote:

On Mar 16, 3:23 am, HW@....(Henri Wilson) wrote:
On 15 Mar 2007 19:43:54 -0700, "Jerry" wrote:


You are obviously not up on the latest research. With
recent advances in supercomputer capabilities, it has been
possible for astrophysicists to include in their models
effects that previously had to be ignored, because modeling
those effects required computational power far exceeding
that which had been available.


The state of the art in Cepheid modeling as of early 2005
is described in the following link:
http://www.lesia.obspm.fr/astro/cepheids/program.html


In the last couple of years, I've seen even better results!


Seehttp://www.users.bigpond.com/hewn/bunching.jpg
....then burn all yer books...


All you have in the above link is a bunch of cartoons.

Show me that you can simultaneously match the luminosity
and radial velocity curves of RT Aurigae.

Thus far, you have done nothing but emit a lot of hot
air.

Your version of huff-puff, I suppose.


Why don't you concentrate on delivering babies?

Physics is obviously way over your head...

Jerry



"When a true genius appears in the world, you may know
him by this sign, that the dunces are all in confederacy against him."
--Jonathan Swift.
  #463  
Old March 16th 07, 09:45 PM posted to sci.physics.relativity,sci.astro
Henri Wilson
external usenet poster
 
Posts: 1,378
Default Why are the 'Fixed Stars' so FIXED?

On Fri, 16 Mar 2007 10:17:25 GMT, "Androcles"
wrote:


"Jerry" wrote in message ups.com...
On Mar 16, 3:23 am, HW@....(Henri Wilson) wrote:
On 15 Mar 2007 19:43:54 -0700, "Jerry" wrote:


You are obviously not up on the latest research. With
recent advances in supercomputer capabilities, it has been
possible for astrophysicists to include in their models
effects that previously had to be ignored, because modeling
those effects required computational power far exceeding
that which had been available.

The state of the art in Cepheid modeling as of early 2005
is described in the following link:
http://www.lesia.obspm.fr/astro/cepheids/program.html

In the last couple of years, I've seen even better results!

Seehttp://www.users.bigpond.com/hewn/bunching.jpg
....then burn all yer books...


All you have in the above link is a bunch of cartoons.

Show me that you can simultaneously match the luminosity
and radial velocity curves of RT Aurigae.

Thus far, you have done nothing but emit a lot of hot
air.


HAHAHA!
Pot. Kettle. Black.


Hahahaha!
The realisation that all previously calculated velocities are likely to be 90
degrees out, is too much for her/him/it.



"When a true genius appears in the world, you may know
him by this sign, that the dunces are all in confederacy against him."
--Jonathan Swift.
  #464  
Old March 16th 07, 10:00 PM posted to sci.physics.relativity,sci.astro
Jerry
external usenet poster
 
Posts: 502
Default Why are the 'Fixed Stars' so FIXED?

On Mar 16, 4:39 pm, HW@....(Henri Wilson) wrote:
On 16 Mar 2007 03:07:27 -0700, "Jerry" wrote:

On Mar 16, 3:23 am, HW@....(Henri Wilson) wrote:


Seehttp://www.users.bigpond.com/hewn/bunching.jpg
....then burn all yer books...


All you have in the above link is a bunch of cartoons.


Show me that you can simultaneously match the luminosity
and radial velocity curves of RT Aurigae.


Thus far, you have done nothing but emit a lot of hot
air.


Your version of huff-puff, I suppose.


Why don't you concentrate on delivering babies?

Physics is obviously way over your head...


As a matter of fact, my final rotation will be in OB-GYN.
I planned it that way because that's what I thought I would
wind up specializing in. Certainly the rotation that I just
finished up has taught me that psychiatric medicine isn't
my thing.

Jerry

  #465  
Old March 16th 07, 10:49 PM posted to sci.physics.relativity,sci.astro
Henri Wilson
external usenet poster
 
Posts: 1,378
Default Why are the 'Fixed Stars' so FIXED?

On 16 Mar 2007 15:00:16 -0700, "Jerry" wrote:

On Mar 16, 4:39 pm, HW@....(Henri Wilson) wrote:
On 16 Mar 2007 03:07:27 -0700, "Jerry" wrote:

On Mar 16, 3:23 am, HW@....(Henri Wilson) wrote:


Seehttp://www.users.bigpond.com/hewn/bunching.jpg
....then burn all yer books...


All you have in the above link is a bunch of cartoons.


Show me that you can simultaneously match the luminosity
and radial velocity curves of RT Aurigae.


Thus far, you have done nothing but emit a lot of hot
air.


Your version of huff-puff, I suppose.


Why don't you concentrate on delivering babies?

Physics is obviously way over your head...


As a matter of fact, my final rotation will be in OB-GYN.
I planned it that way because that's what I thought I would
wind up specializing in. Certainly the rotation that I just
finished up has taught me that psychiatric medicine isn't
my thing.


......probably because you sat on the wrong side of the consulting room desk....

Why don't you buy one of those "do-it-yourself shock treatment kits".

Jerry



"When a true genius appears in the world, you may know
him by this sign, that the dunces are all in confederacy against him."
--Jonathan Swift.
  #466  
Old March 16th 07, 11:36 PM posted to sci.physics.relativity,sci.astro
Eric Gisse
external usenet poster
 
Posts: 1,465
Default Why are the 'Fixed Stars' so FIXED?

On Mar 16, 1:39 pm, HW@....(Henri Wilson) wrote:
On 16 Mar 2007 03:07:27 -0700, "Jerry" wrote:



On Mar 16, 3:23 am, HW@....(Henri Wilson) wrote:
On 15 Mar 2007 19:43:54 -0700, "Jerry" wrote:


You are obviously not up on the latest research. With
recent advances in supercomputer capabilities, it has been
possible for astrophysicists to include in their models
effects that previously had to be ignored, because modeling
those effects required computational power far exceeding
that which had been available.


The state of the art in Cepheid modeling as of early 2005
is described in the following link:
http://www.lesia.obspm.fr/astro/cepheids/program.html


In the last couple of years, I've seen even better results!


Seehttp://www.users.bigpond.com/hewn/bunching.jpg
....then burn all yer books...


All you have in the above link is a bunch of cartoons.


Show me that you can simultaneously match the luminosity
and radial velocity curves of RT Aurigae.


Thus far, you have done nothing but emit a lot of hot
air.


Your version of huff-puff, I suppose.


Why don't you concentrate on delivering babies?

Physics is obviously way over your head...


....says the guy who posts under a fake name and forged his diplomas
for a newsgroup.

Hey Ralph, do you think you could do even one classical mechanics
problem?


Jerry


"When a true genius appears in the world, you may know
him by this sign, that the dunces are all in confederacy against him."
--Jonathan Swift.



  #467  
Old March 17th 07, 09:33 AM posted to sci.physics.relativity,sci.astro
Jerry
external usenet poster
 
Posts: 502
Default Why are the 'Fixed Stars' so FIXED?

On Mar 15, 12:11 pm, "George Dishman"
wrote:

Henry should enter the values from the above paper
and get his program to calculate the residuals.
Anything else is just handwaving. Now that you have
found the reference, he really has no excuse not to.


Since the link to Gieren (1985) got truncated, I'll repeat
it he
http://articles.adsabs.harvard.edu/c...6A...148..138G

Please refer to Figure 3, the composite radial velocity curve.
An extremely important point to make, is that most of the
scatter evident in this composite curve is -not- due to random
measurement error, but rather represents cycle-to-cycle
variations in the shape and timing of individual Cepheid
pulsations. Random scatter in Gieren's measurements amounted
about +/-0.5 km/s, while random measurement error in Duncan's
1908 curves amounted to somewhat over +/- 1 km/s. The
scatter evident in the Figure 3 composite curve considerably
exceeds anything that can be attributed to measurement error.

The photometric measurement technique available around the turn
of the last century (measuring the photographic density of
deliberately out-of-focus stellar images) was accurate to
several hundredths of a magnitude. Because of this high
accuracy of measurement, random variation in the cycle-to-cycle
timing of Cepheid luminosity curves ("period noise") as well as
variations in cycle-to-cycle maxima/minima ("amplitude noise")
were well established by the time that Shapley wrote his
seminal 1914 article, "On the Nature and Cause of Cepheid
Variation".
http://adsabs.harvard.edu/abs/1914ApJ....40..448S

Prior to 1914, the dominant opinion was that Cepheids were
probably a form of binary star, whose variable brightness might
be due to such effects as, say, tidal influences. (Indeed,
Duncan's 1908 paper dwells at length on the possibility of
Cepheid variation being due to an asymmetric rotating layer of
absorbing material.) After 1914, it became generally recognized
that the binary star hypothesis could not be reconciled with
the existence of period noise and amplitude noise in Cepheid
luminosity curves, and so the binary star hypothesis was
abandoned.

As you have pointed out to Henri, a requirement for stable
orbits places severe constraints on the the types of variation
which could be accommodated in a Cepheid luminosity or radial
velocity curve. One cannot just toss in a third body to try
to explain period noise.

Jerry

  #468  
Old March 17th 07, 02:00 PM posted to sci.physics.relativity,sci.astro
George Dishman[_1_]
external usenet poster
 
Posts: 2,509
Default Why are the 'Fixed Stars' so FIXED?


"Henri Wilson" HW@.... wrote in message
...
On Fri, 16 Mar 2007 16:59:26 -0000, "George Dishman"
wrote:
"Henri Wilson" HW@.... wrote in message
. ..


... I doubt if the published one is particularly accurate.


_You_ calculate the accuracy by statistical techniques,
that's what get you the error bars. You can also estimate
systematics but factors like mis-calibration should apply
equally regardless of orbital phase.

Then those curves will almost certainly be failures too, you
cannot have a stable configuration with a third object except
under _very_ limited conditions (e.g. figure of eight or the
very disparate separations like the Sirius system).


George, does Jupiter have moons and orbit the sun?
Does the Earth have a moon George and orbit the sun?


OK, I should have also said "very disparate masses". There is
an upper limit of a mass ratio of ~24:1 for the Lagrange point
stability.

http://en.wikipedia.org/wiki/Lagrangian_point#Stability


I don't think you have fully realised the complexity of this whole issue
George.


I don't think you realise the complexity of the effect of
speed unification on VDoppler ;-)

I don't think you realise the constraints Keplerian orbits
place on you Henry.


George, there are probably 10 billion stars in our galaxy, most with
companions
and orbiting planets.
Do you really think we know every possible configuration just by
investigating
our own solar system?


No, I think we can eliminate unstable configurations by
applying Newton's Laws (relativistic effects are small).

However my program IS strictly limited to Keplerian orbits. I introduced
the
phase variation to investigate Lagrange points....and found evidence that
objects DO exist at the 60 degree one.


What mass ratio?

George


  #469  
Old March 17th 07, 07:35 PM posted to sci.physics.relativity,sci.astro
Henri Wilson
external usenet poster
 
Posts: 1,378
Default Why are the 'Fixed Stars' so FIXED?

On 17 Mar 2007 07:00:46 -0700, "George Dishman"
wrote:


"Henri Wilson" HW@.... wrote in message
.. .
On Fri, 16 Mar 2007 16:59:26 -0000, "George Dishman"
wrote:



... I doubt if the published one is particularly accurate.


_You_ calculate the accuracy by statistical techniques,
that's what get you the error bars. You can also estimate
systematics but factors like mis-calibration should apply
equally regardless of orbital phase.


Sure....and 'error bars' can come in very handy when one wants to fiddle the
results.

Ain't stats wonderful?

Then those curves will almost certainly be failures too, you
cannot have a stable configuration with a third object except
under _very_ limited conditions (e.g. figure of eight or the
very disparate separations like the Sirius system).


George, does Jupiter have moons and orbit the sun?
Does the Earth have a moon George and orbit the sun?


OK, I should have also said "very disparate masses". There is
an upper limit of a mass ratio of ~24:1 for the Lagrange point
stability.

http://en.wikipedia.org/wiki/Lagrangian_point#Stability


yes yes, theories theories.

Three body problems are not easily solved generally....let alone four of five
body problem...

I don't think you have fully realised the complexity of this whole issue
George.


I don't think you realise the complexity of the effect of
speed unification on VDoppler ;-)


I am not worrying about speed unification at the moment. The chancess are its
effect is much less than I thought it was. Rather, my 'distance discrepancies'
are largely due to orbit pitch.

I don't think you realise the constraints Keplerian orbits
place on you Henry.


George, there are probably 10 billion stars in our galaxy, most with
companions
and orbiting planets.
Do you really think we know every possible configuration just by
investigating
our own solar system?


No, I think we can eliminate unstable configurations by
applying Newton's Laws (relativistic effects are small).


That would be nice..

However my program IS strictly limited to Keplerian orbits. I introduced
the
phase variation to investigate Lagrange points....and found evidence that
objects DO exist at the 60 degree one.


How can YOU explain a curve like this one:

http://www.britastro.org/vss/gifl/00064.gif

It's certainly not a simple overtone.

...but the dip can be explained with an object rotating in the same orbit but
with 60 degree lag.

see S Cas in:
www.users.bigpond.com/hewn/group1.jpg

Mine is the yellow curve....a perfect fit...

Unfortunately, however, I cannot explain the claimed magnitude change of about
9. In fact I don't believe it. According to the britastro website, there is a
group of stars that appears to have very large changes in brightness. How do
YOU explain those? I think somebody forgot to convert to a log scale.



What mass ratio?


You can get an estimate from the relative sizes of the dip and main curve. I
would say about 4:1 .


George



"When a true genius appears in the world, you may know
him by this sign, that the dunces are all in confederacy against him."
--Jonathan Swift.
  #470  
Old March 17th 07, 07:39 PM posted to sci.physics.relativity,sci.astro
Henri Wilson
external usenet poster
 
Posts: 1,378
Default Why are the 'Fixed Stars' so FIXED?

On 17 Mar 2007 02:33:52 -0700, "Jerry" wrote:

On Mar 15, 12:11 pm, "George Dishman"
wrote:

Henry should enter the values from the above paper
and get his program to calculate the residuals.
Anything else is just handwaving. Now that you have
found the reference, he really has no excuse not to.


Since the link to Gieren (1985) got truncated, I'll repeat
it he
http://articles.adsabs.harvard.edu/c...6A...148..138G

Please refer to Figure 3, the composite radial velocity curve.


Hahahohohoho!

Haven't you noticed that it is virtually the same as the brightness curve?

I now know that the two ARE the same. When we measure brightness changes, we
are also looking at the velocity curve.
The problem is that observed brightness variations are a combination of
contributions from numerous members of a binary/ternary system and are quite
different from the brigthness curve of individual members.

An extremely important point to make, is that most of the
scatter evident in this composite curve is -not- due to random
measurement error, but rather represents cycle-to-cycle
variations in the shape and timing of individual Cepheid
pulsations. Random scatter in Gieren's measurements amounted
about +/-0.5 km/s, while random measurement error in Duncan's
1908 curves amounted to somewhat over +/- 1 km/s. The
scatter evident in the Figure 3 composite curve considerably
exceeds anything that can be attributed to measurement error.

The photometric measurement technique available around the turn
of the last century (measuring the photographic density of
deliberately out-of-focus stellar images) was accurate to
several hundredths of a magnitude. Because of this high
accuracy of measurement, random variation in the cycle-to-cycle
timing of Cepheid luminosity curves ("period noise") as well as
variations in cycle-to-cycle maxima/minima ("amplitude noise")
were well established by the time that Shapley wrote his
seminal 1914 article, "On the Nature and Cause of Cepheid
Variation".
http://adsabs.harvard.edu/abs/1914ApJ....40..448S

Prior to 1914, the dominant opinion was that Cepheids were
probably a form of binary star, whose variable brightness might
be due to such effects as, say, tidal influences. (Indeed,
Duncan's 1908 paper dwells at length on the possibility of
Cepheid variation being due to an asymmetric rotating layer of
absorbing material.) After 1914, it became generally recognized
that the binary star hypothesis could not be reconciled with
the existence of period noise and amplitude noise in Cepheid
luminosity curves, and so the binary star hypothesis was
abandoned.


Then why do most cepheids appear to have companion stars?

As you have pointed out to Henri, a requirement for stable
orbits places severe constraints on the the types of variation
which could be accommodated in a Cepheid luminosity or radial
velocity curve. One cannot just toss in a third body to try
to explain period noise.


I actually pointed that out to George. I said the presence of a harmonic or a
90 degree phase shift can hardly be explained by orbital considerations alone.
That doesn't rule out the possibility that another unknown factor is involved.

Jerry


Jerry let me ask you a serious question.

If a pulsar is moving around an orbit, how can the speed of an emitted pulse
magically adjust to that of all previously emitted pulses?

Do you still believe in an absolute aether?





"When a true genius appears in the world, you may know
him by this sign, that the dunces are all in confederacy against him."
--Jonathan Swift.
 




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