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Old September 10th 12, 04:31 PM posted to sci.astro.research
Richard D. Saam
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Default Beyond IDCS J1426.5+3508

On 7/1/12 3:00 AM, Phillip Helbig---undress to reply wrote:
In article , "Richard D. Saam"
writes:

How about framing the question in terms of a more defined
Supernovae Type 1a standard candle condition.

Use the distance modulus equation:

m-M = 5 log(d) - 5

then d = 10^((m-M)/5 - 1)

From Supernovae compilation
http://supernova.lbl.gov/Union/figur....1_mu_vs_z.txt

the current maximum Type 1A redshift
2003dy z = 1.34 m-M = 45.0675055813

d = 10^((m-M)/5 - 1) = 1.03E+08 parsec or 3.18E+26 cm


I haven't checked the actual numbers, but OK so far.

This is about 2.5 percent of the present universe


First, note that the distance involved is the luminosity distance.
There is little point in expressing this in terms of the

radius


of the universe.

luminosity distance is a distance measured by luminosity but a distance
is a distance and a function of z.
It is understood that universe radius is subject to the particular model
used and can be expressed as a function of z
A model can be used wherein the Hubble sphere expands at c

assuming expansion from the Big Bang
at the speed of light c/H = 1.30E+28 cm


Not sure what you mean here. The speed of light is not a limiting
factor for the expansion of the universe.


The speed of light is not in the general view a limiting factor for the
expansion of the universe
but this view does not negate the possibility that it is.

If z=1.34, then the universe is 2.34 times larger now than when the
light was emitted. This is independent of the cosmological model.

In the limited view, one could consider that 2.34 larger based on speed
of light

So why does type 1A 2003dy standard candle redshift (z=1.34)
represent a condition within ~2.5% of the Big Bang
with its z in the thousands and probably much greater?


I do not understand this. What does the "z in the thousands" mean?


"z in the thousands" in the context that the first light was at z~1000