Re: Confusion in Expanding Confusion

On Nov 2, 6:34 pm, dwhig...@xxxxxxxxxxxx wrote:
On Nov 1, 5:42 pm, dwhig...@xxxxxxxxxxxx wrote:





On Oct 30, 7:43 am, mluttg...@xxxxxxxxxx wrote:

On Oct 28, 2:05 pm, tamaras...@xxxxxxxxx wrote:

Thanks Marcel. Yes, we did indeed make a mistake in our derivation of
the special relativistic description of velocities in an expanding
universe. This is shown nicely in Chodorowski 2005 (Publications of
the Astronomical Society of Australia, 22, 287). It comes down to a
simple switch... in our derivation we mistakenly used the value of
Hubble's constant at the time of emission when we should have used it
at the time of observation. In the empty universe these differ from
each other by a factor of (1+z).

You may also want to see the following excellent papers on this topic.

Barnes, Francis, James and Lewis (2006), MNRAS 373, 382: "Joining the
Hubble flow: implications for expanding space"

Francis, Barnes, James and Lewis (2007), Publications of the
Astronomical Society of Australia, 24, 95: "Expanding Space: the Root
of all Evil?"

Grøn and Elgarøy, (2007), American Journal of Physics 75, 151: "Is
space expanding in the Friedmann universe models?"

Thank you for the interesting references, for instance this one:

Is space expanding in the Friedmann universe models?http://arxiv.org/PS_cache/astro-ph/pdf/0603/0603162v2.pdf

Authors: Oyvind Gron (Oslo College, Faculty of Engineering)
Oystein Elgaroy (Institute of theoretical astrophysics,
University of Oslo)
(Submitted on 7 Mar 2006 (v1), last revised 18 Sep 2006
(this version, v2))

"Abstract: The interpretation of the expanding universe as
an expansion of space has recently been challenged.>From the geodesic equation in Friedmann universe models

and the empty Milne model, we argue that a Newtonian
or special relativistic analysis is not applicable on large scales,
and the general relativistic interpretation in terms of expanding
space has the advantage of being globally consistent.
We also show that the cosmic redshift, interpreted as
an expansion effect, containts both the Doppler effect
and the gravitational frequency shift."

Indeed, the SR formula
SR vrec(z) = c * ((1 + z)2 - 1) / ((1 + z)2 + 1)
cannot be correct, contrary to, in my opinion, the SR formulae
SR vrec(z) = cz / (1+z)
d = (c/H0) * z/(1+z).

For instance, with 1/Ho = 13.666 Gyr and z = 1.7, this last
formula gives a light travel time of 8.605 Gyr, against
9.773 Gyr with GR, cf. Ned Wright's calculator:http://www.astro.ucla.edu/~wright/CosmoCalc.html
"Ho = 71, OmegaM = 0.270, Omegavac = 0.730, z = 1.700
It is now 13.666 Gyr since the Big Bang.
The light travel time was 9.773 Gyr."

Thus, at z = 1.7, the distance of a supernova is about
14% closer when calculated with the SR formula.
Interestingly, GR specialists claim that such supernova is
brighter than expected, hence that the expansion rate
of the universe is accelerating.

Marcel Luttgens- Hide quoted text -

- Show quoted text -

I'm responding to the last paragraph. My information is that the high
z supernovae research teams used the same methods throughout and found
IaSne up to z = 1 were DIMMER than expected and concluded the
expansion of the universe was accelerating. Later, after observing
IaSne at red shifts above z = 1 they found the Ias were BRIGHTER than
expected using the same methods of calculation. The conclusion was
that the expansion rate had shifted about 7 billion years ago. The
reason for this conclusion was that to conclude otherwise would prove
me right and Einstein wrong. Dwain W. Higginbotham- Hide quoted text -

- Show quoted text -

Some additional musings. You talk about a IaSne at a red shift of 1.7
being 14% different in distance depending on whether you're using GR
or SR math. This is probably the same 1.7 IaSne mentioned in
Kirshners' "Science" article where he didn't specify what math he was
using, but if he used yours, the IaSn would have been 14% different
one way or the other. Instead, it was 1,000% BRIGHTER than he
expected.
Also, funny you should mention Ned Wright. I have apprised him of
all these ideas recently, and gotten no response. Likewise, Robert
Kirshner. Its interesting Tamara Davis is involved in this. I offered
her $10,000 a year ago if she could dissuade me regarding the local
group orbiting the center. Regards, DWH

See "Observational Evidence from Supernovae for an Accelerating
Universe and a Cosmological Constant", by Riess & al.
http://arxiv.org/PS_cache/astro-ph/pdf/9805/9805201v1.pdf

From abstract:

"The distances of the high-redshift SNe Ia are, on average,
10% to 15% farther than expected in a low mass density
(OmegaM = 0.2) Universe without a cosmological constant."

Note that at z = 1.7, the distance of a supernova is about
14% closer than the distance obtained with GR when calculated
with the formula d = (c/H0) * z/(1+z).
Iow, this formula gives the "expected" value.

Note also that the formula d = (c/H0) * z/(1+z) also
applies in a stable universe.

Marcel Luttgens

.

Relevant Pages