sci.physics.relativity

Henri Wilson wrote:
> On Tue, 07 Aug 2007 14:22:28 +0200, "Paul B. Andersen"
> < @ > wrote:
>
>> Henri Wilson wrote:
>>> On Sat, 04 Aug 2007 19:42:11 +0200, "Paul B. Andersen"
>>> < @ > wrote:
>
>>>>>> When you cannot answer, talk about something else.
>>>>> There was a time when your posts were quite intelligible. Not any more....
>>>> I think this should be intelligible even for you:
>>>>
>>>> 1. The BaTh has no explanation for why the temperature of
>>>> a Cepheid varies during the period.
>>> It doesn't need one. What the hell does adiabatic compression have to do with
>>> the BaTh?
>> 1. YOU claim that most cepheids really are orbiting stars,
>> and that the luminosity variation is not intrinsic.
>
> I don't. I accept many are probably huffpuffs.
> There are however, other ways a second harmonic can be included in their
> curves...so I'm still open minded about it.
>
>> 2. It is a fact that the surface temperature of all
>> cepheids varies a lot during the period.
>
> That's based on willusory data..
>
>> 3. The BaTh have no explanation for why the surface temperature
>> of an orbiting star should vary during the period.
>
> It should follow normal adiabatic expectations...related to the TRUE velocity
> curves. ..but as I stressed to George, both the OBSERVED temperature and
> velocity curves are willusions...so one really can't be sure of anything.

Cepheids are quite well understood.
The pulsation isn't 100% adiabatic. The well known driving mechanism
(variation in the opaqueness of the atmosphere) make it deviate
from adiabatic pulsation.

>> "It doesn't need one", indeed! :-)
>
> One doesn't
>
>>>> 2. The BaTh has no explanation for the luminosity - period
>>>> relation of Cepheids.
>>> If they are orbiting stars mistaken identified as huffpuffs, it does. If they
>>> are genuine huffpuffs, then the period is not BaTh related at all.
>> 1. YOU claim that most cepheids really are orbiting stars,
>> and that the luminosity variation is not intrinsic.
>
> You are behind the times Paul.
> Many are huffpuffs, many could be orbiting stars.

Oh no, Henri. You cannot have it both ways.
There are so many characteristics about a Cepheid that
there is no way the BaTh can predict an orbiting star
to look like a Cepheid.
By assuming physical impossible orbital parameters,
you can mimic the light-curve, that's all.
The BaTh is utterly unable to predict the observed
variation in spectrum and temperature.

I think you now have admitted that _all_ cepheids
are pulsating stars.

>
>> 2. It is a fact that it is a very strong correleation between
>> the period and the luminosity of cepheids.
>> 3. The BaTh have no explanation for why the luminosity
>> of an orbiting star should be correlated with the orbital
>> period.
>>
>> You have tried to explain the correlation between
>> period and luminosity before, here are two of your explanations:
>
> You are behind the times.
>
>> Henri Wilson wrote:
>> | The closer they are to each other, the hotter will
>> | be the daytime side and the bigger the day/night
>> | fluctuation. So close stars will, on average,
>> | be hotter than distant ones.
>>
>> Henri Wilson wrote:
>> | What ballistician would have had the brains
>> | to deduce that, on average, bigger stars are
>> | brighter and should orbit more slowly?
>>
>> Hilarious, no? :-)
>
> On average, they will orbit more slowly around their planet barycentres.
>
> Period = K.(r^3/M)^
>
> .....assume average r increases with M.

There is no use, Henri.
There is no way you can make the BaTh predict the observed
luminosity - period relationship.


But why the hell to I waste my time in this idiotic nonsense?

Paul