🚀 go-pugleaf

On Thu, 16 Aug 2007 07:44:41 -0700, dlzc <dlzc1@cox.net> wrote:

>Dear John C. Polasek:
>
>On Aug 15, 6:50 pm, John C. Polasek <jpola...@cfl.rr.com> wrote:
>> On Wed, 15 Aug 2007 09:09:52 -0700,dlzc<dl...@cox.net> wrote:
>> >Dear John C. Polasek:
>>
>> >On Aug 14, 6:00 pm, John C. Polasek <jpola...@cfl.rr.com> wrote:
>> >...
>> >> I think the solution is a lot easier than jiggling with G.
>> >> Isn't redshift the only way to measure such distances?
>> >> They find that the observed intensity is less than
>> >> expected from red-shift distance.
>>
>> >No, redshift is not the only way.  If there are type Ia
>> >supernovae located in the "structure", there is the
>> >duration of the decay from peak to some percentage
>> >of peak.  There is intensity of the source (1/r^2,
>> >regardless of source... *assuming* something about
>> >the source).  All these methods agree to within the
>> >margin of error in the paper I saw.
>>
>> I didn't mean it's the only way; I meant it conflcts
>> with the intensity readings.
>
>The only paper that I am aware of, *all* the disparate measurements
>agree to within their margin of error.
>
>> The disparity between redshift and intensity
>
>Do you have a citation?  Is intensity higher or lower than redshift
>would indicate?
>
>> is what's causing all the expansion talk.
>
>Expansion is what redshift (and stretching of duration, and decrease
>in intensity) is all about.  The "disparity" serves to describe
>something other than expansion.  There are a pretty good number of
>factors that can produce this disparity, although anomalously more
>intensity with distance might be a bit of a challenge.
>
>> There's no agreement except as to disagreement.
>> And so I'm asking the modality of the red shift /
>> distance calculation, is it doppler, is it scale factor,
>> is it the relativistic doppler?
>
>http://www.astro.ucla.edu/~wright/cosmo_01.htm
>.. so you get from 1+z to distance via a linear transformation ("scale
>factor").
>
>Doppler really doesn't give you distance, just change in distance.
It should give recession velocity, from which a proper H0 would give
distance. 
>And you can't integrate over time, because we don't know the time
>without *assuming* what we set out to measure.
>
>> The discrepancy might be corrected with proper
>> algebra, instead of dark energy.
>
>Get rid of Dark Matter, and there is almost no need for Dark Energy.
>MOND almost works, and TeVaS does work (as far as I know) at getting
>rid of Dark Matter.
>
>David A. Smith
Excuse my error: what I meant was acceleration, not expansion.
Acceleration of expansion rate is the current big phenomenon being
investigated, in which it is universally presented that the observed
intensity of SN1A's is lower than might be expected by square law
1/D^2. 
No question, you can measure redshift. From it there are several ways
of deducing distance. But nowhere do I see it displayed, what equation
is being used. 
From astro.ucla (above) you imply a/a0 = 1+z from which 1/D^2 would be
proportional to 1/(1+z)^2 but the observed intensity is markedly
lower.
Time dilation applied to the decay curve is some part of the analysis,
but that calculation implies recession velocity, not a/a0.
The papers I have read are quite abstruse, trying to get a handle on
the impact of "quintessence", I believe. 
It seems there's plenty of places to scrutinize the transformation
from redshift to distance or time dilation to distance, enough room
for simple error to explain away acceleration.
John Polasek