On Fri, 16 Feb 2007 14:43:52 +0000 (UTC), bz
wrote:

HW@....(Henri Wilson) wrote in

I think you mean asymtotic(with most of the unification very early)
rather than exponential.

Yes I have often described it as asymptotic...similar really.

Inverse exponential is asymtotic, exponential, on the other hand, grows
without limit.

Yes everyone should know what I meant by 'exponential'.
..
The method I use is to reduce the difference between actual speed and c
by a fixed factor per unit distance.

If the initial speed relative to the barycentre of the binary is say,
1.00015c, then I multiply the 0.00015 by the extinction rate each light
day of travel.

So, your fast and slow photons have a 'half life'. But you are changing
the speed, not the number of photons at that speed?

correct.

My extinction rates are like '0.9999', '0.999995', etc.
My intention is to determine required extinction rates for various stars
to see if there is a pattern.

I finally devised a neat way to include extinction in my program...so I
can now make some real progress.

However that produces the problem of how can the velocities unify very
close to the stars in question, when they have not traveled very far
yet.

If they travel far enough to bunch up and show variation in brightness,
they will travel far enough (at different speeds) to be coming from
different directions by the time the arrive here.

Very little though.

That depends on the geometry. Currently, all your action occurs along a
single, one dimensional line, and you 'scale' things, using trig, to
'emulate' an orbit with tilts in three space, but you make no allowance for
different 'line of sight' paths that the photons would need to travel.

I know what you are saying and have considered it myself. particularly in the
case of long period orbits where the conditions along the LOS could be quite
different for light emitted, say, one year apart.

I have thought about this myself...if it happens at all it should affect
stars with a large orbit diameter and long period more than say 'contact
binaries'.

Yes, and it would effect those close to us more than those very distant.

Thus it would effect those with high parallax more than those with low
parallax.

Finally, it would effect systems with high proper motion more than those
with low proper motion.

Yes..but I still don't think it's worth worrying about. Mind you, it could
explain some of the erratic behavior often seen in recorded brightness curves.


I also believe that the extinction rate itself decreases with distance
from the source star. That is, most takes place in the vicinity of the
source....maybe in the first couple of LYs of travel.

Use a half life model. Most will be gone within 10 half lives.

I do use a 'half distance' model.

After all, they start out from different places in the sky. The slow
ones come from the side of the orbit where the star is going away from
us. The fast ones come from the side of the orbit whewre the star is
approaching us.

Astronomers have been able to see the wobble of 'nearby' stars that have
large planets, why wouldn't they see the wobble of nearby cephieds?

And why don't those nearby systems with planets show Wilson Variability
in brightness along with the doppler shift and wobble that they display?

The light from these stars still travels throgh similar quality space,
even if it emitted months later.

That does NOT answer the question.

I'm not going to worry about it.

You might say that the light has not traveled far enough yet for it to
bunch up, but then you are contradicting the idea that the velocities
unify rapidly.

It all depends on the star's orbit velocity.

If so, then all doppler binaries, with orbital velocities similar to those
which give the Wilson Curves that match the cephieds, should show similar
variations in brightness.

I dont have enough data to make any definite claims about unification as
yet....except that is appears to happen according to the BaTh.

Of course there are many stars that DO vary intrinsically and maybe I'm trying
to match those with a theory that doesn't apply.

If it is a large orbit with velocities below 0.00001 c, very little
bunching or brightness change will be expected over quite large
distances.

For instance a star in a 1 year orbit moving at 0.00001 c should vary by
only about 0.04 magnitudes at 300 LYs distance without taking into
account any extinction.
At 500 LYs the figure is about 0.065 mag variation.

So all double stars (with the right orbital plane) at great distances
should show large brightness variations.

Without unification they would, yes...but they don't...
That is what I'm trying to explain. There could be other reasons for it.
.....face-on orbits for instance.

bz

please pardon my infinite ignorance, the set-of-things-I-do-not-know is an
infinite set.