Re: Cosmic acceleration rediscovered
From: George Dishman (george_at_briar.demon.co.uk)
Date: 12/04/04
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Date: Sat, 4 Dec 2004 16:18:13 -0000
I'm going to reply in full to this but it's already
much too long. Can I suggest either you do some severe
snipping or I will on my next reply.
"greywolf42" <mingstb@marssim-ss.com> wrote in message
news:ny2sd.1953$fi2.865@news.flashnewsgroups.com...
> George Dishman <george@briar.demon.co.uk> wrote in message
> news:coodmg$k5s$1@news.freedom2surf.net...
>>
>> "greywolf42" <mingstb@marssim-ss.com> wrote in message
>> news:f5Nrd.1533$fi2.68@news.flashnewsgroups.com...
>> > George Dishman <george@briar.demon.co.uk> wrote in message
>> > news:colk2c$r33$1@news.freedom2surf.net...
>
> {snip higher levels}
>
>> >> Hubble's data was all low z so the question didn't arise.
>> >
>> > Precisely!!!!!! Thank you for proving my point.
>>
>> If your point is that Hubble didn't have access
>> to modern data, then I never contested it.
>
> That wasn't my point.
>
>> The
>> fact remains that linearity in the Hubble Law
>> is between speed and distance.
>
> That was my point. Repeatedly.
>
> Now that we're on the same page, I will snip any repetitions of the issue
> about what is contained ... or not contained ... in the Hubble Law.
OK, let's put a stake in the ground and stick to that
from now on, but bear in mind that the distance is
measured at a given epoch, not at the time of emission.
Changing to time of emission makes it non-linear. Sorry
to be repetitious, I know I've pointed it out many times
already, but you seem to keep forgetting it.
>> I have said repeatedly that I'm open to considering
>> alternative assumptions. Whether they can "meet the
>> data" remains to be seen.
>
> Wrong. Google search proves that the first occurrence of the word
> "alternative" in this thread is your mention of Zwicky, 1929, above.
> http://www.google.com/groups?selm=coiqg4%24ss%241%40news.freedom2surf.net
However, two posts before that in
http://groups.google.com/groups?selm=1101246094.62140.0%40despina.uk.clara.net
I said:
> I am happy to acknowledge the possibility of a non-
> linear relationship between redshift and distance at
> a given epoch.
>
> I am happy to consider causes of redshift other than
> motion.
I just didn't use the word "alternative"
In my following post
http://groups.google.com/groups?selm=1101413609.14744.0%40nnrp-t71-03.news.uk.clara.net
I said
"George Dishman" <george@briar.demon.co.uk> wrote in message
news:1101413609.14744.0@nnrp-t71-03.news.uk.clara.net...
>
> ... the observed relation
> between red-shift and distance is a combination of
> the relation between redshift a given epoch together
> with the time variation of any parameters in the
> former. Either or both (or even neither) could be
> non-linear but the combination should match the
> (non-linear) observed data. ...
Prior to those the conversation was mostly about
the proportionality in the Hubble Law.
>> >> No, we are discussing your claims that linearity of the
>> >> Hubble Law is assumed in modern Big Bang theory.
>> >
>> > No, we are discussing the assumption that redshift and speed are always
>> > directly related. We aren't discussing the BB theory.
>>
>> Sorry, go check the messages that started this.
>
> I did, and you are wrong again. The message that began this was my post
> in
> sci.astro, of a reply that was banned in s.a.r:
> http://www.google.com/groups?selm=pDShd.26%24l66.6%40news.flashnewsgroups.co
> m
>
> There is no mention of the big bang at all in that post. I quote: "The
> "Hubble's law" to which you are referring is a theoretical construct.
> Hubble's data connects distance with redshift -- not with recession
> velocity."
True, I got that wrong.
<snip>
> Now, can we get back to the physics of redshift and speed, and the SN1a
> data?
I think it better not to reintroduce that, let's finish
discussing Tired Light first.
> {snip higher levels}
>
>> >> Actually, you haven't discussed any alternative, you
>> >> have only acussed me of assuming the conventional
>> >> theory is the only possibility. That isn't true.
>> >
>> > You finally admitted it on the last round.
>>
>> I admitted no such thing. What I said was that the fact
>> that I am willing to consider alternatives hadn't been
>> clear in previous posts. It still remains true.
>
> You finally admitted that tired light theories were conceivable in the
> prior
> round. That was the first mention of any alternative.
You miss my point, I have never admitted "assuming the
conventional theory is the only possibility." because
it isn't true. Whether we have talked about alternatives
or not is beside the point. You may have incorrectly
presumed that I thought the conventional model was "the
only possibility" but that is not the case. As I point
out elsewhere, I was aware of alternatives at least three
years ago.
>> > So, while your statement is
>> > literally true, it is disingenuous.
>>
>> I would say the same of your attempt to suggest I
>> admitted something when it is obvious I didn't.
>
> My statement was that you had finally admitted to an alternative in that
> post. Not that you admitted to refusing to consider them, prior to that
> post.
No, your claim was that I had admitted "assuming the
conventional theory is the only possibility." That is
untrue. It is true that we only discussed alternatives
recently but that is another matter.
> (A)
>
>> >> >> What I can't grasp is why you keep charging an open
>> >> >> door. I am aware of the current interpretation and
>> >> >> of Zwicky's 1929 alternative of exponential photon
>> >> >> energy degradation, commonly known as "Tired Light".
>> >> >> That has an exponential relationship between redshift
>> >> >> and distance but is ruled out in other ways.
>> >> >
>> >> > Finally, we come to your real objections!
>> >> >
>> >> > Citation(s), please.
>> >>
>> >> Well the most obvious is the intensity of the CMBR:
>> >>
>> >> http://www.astro.ucla.edu/~wright/tiredlit.gif
>> >>
>> >> The energy degradation variant of Tired light
>> >
>> > Which one? *ALL* tired light theories have energy degradation! (Even
>> > if Ned Wright's strawmen don't fit into this category.)
>>
>> I think it was clear I meant those where individual
>> photons lose energy but are not destroyed.
>
> It wasn't clear at all.
If it wasn't clear, you should have looked back at the
quoted text for the context to see that I was taking
a specific example, not claiming a general result.
> ... All you are doing is demonstrating a fundamental
> ignorance of the subject.
>
>> >> would reduce the energy of each photon but not the flux.
>> >
>> > That is the assumption of the BB.
>>
>> Nonsense, it is simply a consequence of the fact that
>> the number of particles is conserved.
>
> It is assuming that the number of particles is conserved, *while* the big
> bang expansion is going on.
No, the proof applies if the number is conserved even in
a steady state universe. Suppose we were at the centre of
a hot steel sphere of constant size, billions of light
years in diameter (silly, I know but it illustrates the
point), the energy of individual photons would be reduced
in transit by Tired Light but the rate of photons arriving
would not. The result would not match what was measured by
FIRAS.
<snip>
>> > It is not part of all tired light theories.
>>
>> Which is why I tried to indivcate that that argument
>> only applied to a specific subset.
>
> But there is no 'subset'. ...
> Some theories are QM based, retaining photons as a QM entity. Others
> don't.
Thanks for illustrating those two subsets.
>> > (It is true of Vigier's QM version, I believe. But not of
>> > Maxwell's, Olber's, or LeSages.)
>>
>> There may be others as well. I don't pretend to know
>> of all the possibilities but the point is that those
>> in which the red-shift mechanism does not also reduce
>> the flux of photons need to find a way to "meet the
>> data" as you put it from FIRAS.
>
> The data from FIRAS is not a confirmation that the universe expanded.
I didn't say it was, my point stands.
>> Then why waste time above pretending you didn't.
>
> Huh? I never stated that I didn't understand Ned Wright's graphic. My
> prior response was the first one after you brought that strawman in.
My thinking was that, if you understand the graphic,
you must understand that it applies to some Tired
Light theories but not others so why did you pretend
I was saying it disproved _all_ Tired Light theories.
<snip>
>> >> > I suspect you'll simply parrot Misner, Thorne and
>> >> > Wheeler's repetition of Zel'dovich's hand-waving and nonsubstative
>> >> > statements.
>> >>
>> >> I don't have MTW so I don't know what is said. Give
>> >> me a hint.
>> >
>> > Here's a link discussing both Ned Wright and MTW:
>> > http://www.google.com/groups?selm=10apn1e3n8ehn7e%40corp.supernews.com
>> >
>> > And another with more detail:
>> > http://www.google.com/groups?selm=103sf11m3v5a575%40corp.supernews.com
>>
>> See my reply to Bjoern on those threads.
>
> I did. Pretty pathetic wriggling, don't you think?
>
>> Either something
>> got damaged in the cut & paste (maybe MTW's ;-) or I misread
>> the quotes.
>
> Nope. Those are direct quotes. No typos. And you didn't misread them.
If Zel'dovich said:
> "We ask the question: if there were such a process,
and MTW supposedly copied it but it became:
> "If there does not exist any such decay process,
something is wrong. Anyway, it's academic at present
since I didn't use those arguments.
<snip>
>> Anyway, as you can see, I gave you a different argument above.
>
> Hey, I enjoy being proved wrong on that kind of prediction. Even if your
> argument was just a repetition of a vague and hand-wavy effort
It gives a quantitative analysis for an example source
temperature. The only thing hand-wavy is that he cannot
use a specific temperature without a specific Tired Light
model to test. The example illustrates the method.
> by Ned
> Wright, instead of MTW. (Ned seems to have replaced his original MTW
> references after my posts, above.) At least I got to see a new argument!
>> > My point was that the only defense you had was
>> > a 1929 theory by Zwicky (The best you could do was find a different
>> > strawman). You aren't even sure *why* Zwicky is out of favor. But yet,
>> > you use it to claim that *ALL* tired light theories are disproved.
>>
>> That's a lie. Provide a reference.
>
> Look up to (A), above.
I did, and nowhere did I claim it applied to *ALL* tired light
theories.
> (1) "I am aware of the current interpretation and of Zwicky's 1929
> alternative"
> (2) "exponential photon energy degradation, commonly known as 'Tired
> Light'."
> (3) "ruled out in other ways"
>
> And -- laughably -- you provide your own link, below. To the post where
> you
> claim that all tired light theories *are* Zwicky's theory ... because they
> have
> energy degradation.
The relevant text hasn't been snipped and is still above but
let me repeat it here:
>> >> >> ... I am aware of the current interpretation and
>> >> >> of Zwicky's 1929 alternative of exponential photon
>> >> >> energy degradation, commonly known as "Tired Light".
>> >> >> That has an exponential relationship between redshift
>> >> >> and distance but is ruled out in other ways.
Nowhere did I claim the FIRAS data ruled out *ALL* tired
light theories, that was your extrapolation.
>> >> > My point was simply that you are ignoring the possibility that your
>> >> > (and Hubbles, and the BB's) primary assumption is simply incorrect.
>> >> > If all you can do is parrot a claim that *one* 1929 theory is not
>> >> > currently accepted, you are on very thin ice.
>> >>
>> >> I take each on it's merits.
>> >
>> > You don't even know *WHY* Zwicky's theory is out of favor! Yet, you
>> > claimed that *ALL* such theories are disproved,
>>
>> That's a lie too. Provide a reference.
>
> My first sentence, above, is a conclusion. You admitted to not reading
> MTW, before.
True.
> And Ned's website wasn't around in the 1930s.
Also true.
> In this thread, it
> didn't appear that you'd read even Ned's webpage (which used to refer to
> MTW) until the post immediately before.
I've been using his pages since the late 1990's which
is why I knew I could go there to get the FIRAS data
comparison, but he does update them ocassionaly so you
may have got the wrong impression.
> My conclusion was incorrect,
Thank you.
> but
> not without foundation.
I think in fact what misled you was not realising I was
commenting only on those Tired Light theories that lose
energy in a specific way. However, as long as we have
cleared that up, let's move on.
> My claim in the second sentence is shown in (A), and above, item (3). And
> in your own link, farther below. You wouldn't listen to Aladar's claims
> that his theory was different. You insisted that *all* theories are the
> same as Zwicky's.
Aladar's claim was that he was the first person ever to
suggest that Tired Light would produce an exponential
relationship between distance and frequency. I also
pointed out that _his_ theory was falsified by the FIRAS
data. That isn't the same as claiming "*all* Tired Light
theories are the same as Zwicky's."
>> > simply because Zwicky's was. That
>> > is not taking each theory on it's merits!
>
>> >> "Tired Light" is a generic
>> >> term which is why I described energy decay specifically.
>> >> Obviously different mechanisms for the energy loss could
>> >> be subject to different tests.
>> >
>> > Precisely!!!!! Yet you dismissed them all, without even looking.
>>
>> I have never made any such claim. What I said was:
>>
>> >> Actually, you haven't discussed any alternative, you
>> >> have only acussed me of assuming the conventional
>> >> theory is the only possibility. That isn't true.
>>
>> So again you are lying.
>
> Not in the least. You wouldn't even consider the option (of a nonlinear
> spatial relationship of redshift and distance) as a possibility, until
> your
> mention of Zwicky, above.
Technically I mentioned it two posts earlier as I said
way back but that's not the point.
> You always insisted on a "constant of
> proportionality."
Again that is misleading, what I have repeatedly pointed
out is that the proportionality in the Hubble Law is
between speed and distance at_a_given_epoch_. It is also
true that Hubble's data was linear but only because it
covered a very short time span.
>> >> > The point of contention is your bullheaded refusal to even consider
>> >> > something not containing the assumption that redshift is
>> >> > always-and-only connected to motion.
>> >>
>> >> I have repeatedly said I would consider alternatives
>
> Wrong again. Google search proves that the first occurrence of the word
> "alternative" in this thread is your mention of Zwicky, 1929, above.
> http://www.google.com/groups?selm=coiqg4%24ss%241%40news.freedom2surf.net
See the beginning of this post.
>> > You stated that you would only consider alternatives that included the
>> > redshift-speed relationship a constant.
>>
>> That's a lie too. Provide a reference.
>
> Another false claim disproved. From:
> http://www.google.com/groups?selm=Z9bkd.3500%24ry5.1003%40news.flashnewsgrou
> ps.com
> =============
>> > Why are you so fixated
>>
>> Fixated? I mentioned it once purely in the context of
>> the source of the term.
>
> You've used it at least a dozen times in the thread. I'm not talking
> about
> the word use. I'm talking about the assumption that you keep making.
>
>> > on a "constant of proportionality," to the exclusion of
>> > the beginning of an exponential function?
The "constant of proportionality" applies to distance at
a given epoch versus speed. The lie is that I have ever
suggested that I "would only consider alternatives that
included the redshift-speed relationship a constant." To
be clear on that, I have never suggested the redshift was
prportional to speed other than in the first order
approximation for v<<c, and I have specifically said that
redshift is not proportional to speed for high z.
>> > redshift-speed relationship a constant.
>> Apparently it's my turn to expand your mind, they are not
>> exclusive.
>
> Then why do you constantly ignore the possibility that the
> redshift-distance
> relation is an exponential curve?
As I said:
"George Dishman" <george@briar.demon.co.uk> wrote in message
news:1101246094.62140.0@despina.uk.clara.net...
>
> I am happy to acknowledge the possibility of a non-
> linear relationship between redshift and distance at
> a given epoch.
>
> I am happy to consider causes of redshift other than
> motion.
If you ask about a specific theory in which the
relationship is exponential, we can discuss it.
> =============
> And many other locations, where you insist on only considering *only* a
> "constant of proportionality."
I thought we had agreed on that:
>> It is clear to me that Hubble's Law (specifically
>> relating recessional velocity to distance at a given
>> epoch) can be derived from short range linearity of
>> velocity if the universe is homogenous and isotropic
>> at large scales. (You have to show a flaw in some
>> very simple logic to change my mind on that.)
To which you replied:
> I never questioned it. ...
so I am prepared to consider alternatives but only if
you can show a flaw in that logic.
>> >> but until the last few posts, you have griped almost
>> >> entirely about 'linearity'.
>> >
>> > And that is still the issue. The nonlinearity of the data. Versus the
>> > linearity of the theory.
>>
>> And again you try to create the strawman.
>
> Strawman? It's the starting point of the original post in the thread in
> this newsgroup! As documented, above.
Yes it was, and it was a strawman then too.
>> The linearity
>> in the theory is between speed and distance while the
>> data relates redshift and distance, or more accurately
>> redshift and magnitude of standard candles.
>
> Yes. That's my point.
You said "The nonlinearity of the data. Versus the linearity
of the theory." implying these were in conflict. That would
only be true if the linearity in the theory applied to the
relationship between redshift and distance. The strawman
theory you are trying to imply is one in which that was the
case. Of course it would be easy to demonstrate such a theory
was wrong, but then that's the purpose of a strawman, it's
easy to knock down.
>> > Eventually, you wore down to admitting that tired light theories
>> > existed.
>>
>> ROFL! You really are a card. Do your research, find out
>> who told Aladar Stolmar that he wasn't the first to
>> propose that tired light had an exponential relationship
>> to distance:
>>
> http://www.google.com/groups?selm=995811704.12706.0.nnrp-10.9e989a91@news.de
> mon.co.uk
>>
>> That was over three years ago.
>
> LOL! And that old post demonstrates that you haven't learned much. You
> are
> fighting by invoking the same set of strawman sources as you were then!
The same data is just as effective now as it was then.
> Aladar was trying to point this out, but you simply avoided the issue by
> claiming that Zwicky's theory was considered disproved, so his theory must
> be too. Even though Aladar pointed out the strawman nature of Ned's
> (repeated) argument.
Ned's argument was valid but he made a mistake in
thinking the upper limit in Aladar's Basic program
was a physical limit in the theory. I talked to
Aladar about that and he told me it was a bodge he
put in because his software took about 20 hours to
run. He needed to integrate to infinity but couldn't
do the maths so ran it until he felt the results had
stabilised as very distant sources had negligible
effect on the results. Correcting Ned's error would
make the fit worse.
> And since you knew better, why did you play dumb for so long in this
> thread?
> (Your position in this thread was that a nonlinear distance-redshift
> relationship was not an option.)
Again that is a lie. My 'postion' as you call it was
that Aladar's theory could not match the FIRAS data.
As a separate topic, I pointed out that the exponential
form was obvious and that Zwicky had published it first.
Aladar's claim to originality was false.
>> Still you seem to be
>> enjoying yourself, beating about the bush, so I'll
>> just wait for you to get wherever your're going.
>
> LOL!
>
>> > But you claimed they were not viable on other grounds. Even though you
>> > didn't know offhand what those "grounds" were.
>> >
>> >> I hope you now realise
>> >> that criticism of current conventional cosmology is
>> >> not valid.
>> >
>> > We aren't discussing criticism of "conventional cosmology." But about
>> > a
>> > single issue. Whether the assumption direct, linear relationship
>> > between redshift and speed is valid.
>>
>> Again you try to slip in the strawman,
>
> It's not a strawman. It is the first statement of the first post in the
> thread in this newsgroup.
You are describing a ficticous theory in which redshift
should be proportional to distance even at high redshift.
That is a strawman, a distrotion of the actual Big Bang
models that you would find easier to discredit.
>> I am not aware
>> of _any_ theory that uses such a relationship other than
>> as an approximation when v<<c.
>
> Yet we just discussed tired light a few lines above.
I am only aware of exponential or near-exponential
relationships in Tired Light theories as we discussed
before. I don't know of any theories, tired light or
otherwise, in which redshift is proportional to distance
for all distances.
>> In conventional theory
>> the proportionality is between speed and distance at
>> a given epoch while redshift is given by the change in
>> scale factor a(t).
>
> Here comes the "epoch" stuff again. And "conventional" theory.
And it will continue to appear until you stop trying
to create a strawman theory in which it is redshift
would be proportional to distance.
> Yet the subject is the difference between observation and theory.
Whatever the subject, I will continue to correct you
each time you try to raise your strawman.
>> > Or whether tired light theories -- which
>> > predicted the data that big bangers now claim for "dark energy" -- can
>> > be considered.
>>
>> Of course they can be considered, but as you said, they
>> must be consistent with the data. Different theories
>> may be best tested against different data
>
> ROTFLMAO!!! They all have to be tested against the *same* data!
Heh, you got me on that one. I meant that particular
data may be able to falsify some theories but not others.
>> so stop
>> handwaving and start discussing specifics. Otherwise
>> all I can do is give you general indications of the
>> tests that can be applied.
>
> Well, one test was the prediction of the nonlinearity discovered in the
> SN1a
> data. That big-bangers now classify as "dark energy."
Again you imply the strawman of expected linearity in the
SNe data. What is described as "dark energy" is the unknown
cause of the _deviation_ from the predicted _non-linearity_
which, in the conventional model, implies expansion is now
accelerating. The Hubble Law remains linear.
George
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