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Hi Steve, Burkhard & All,
Thanks for your comments.
I am just 90 years late in coming up with this idea which, against
the background of cosmological time, is instantaneous.
But seriously, I am heartened that 'tired light' has been considered.
And will have a look at Wikipedia. and other sources.
I think we all agree that science is self correcting but, because
humans and reputations of individuals/institutions are involved this can
take lifetimes to winnow out the chaff and wrong turns..
Even simple systems like the light mill (Crookes Radiometer) ran
through a gauntlet of explanations before the perhaps final explanation
prevailed.
And sometimes equipment is not up to the task. Cold fusion sounded
too good to be true and it was; an artifact due to their having used a
galvanometer which could register only energy released instead of a null
point galvanometer.
The comment about most distant objects appearing to travel away at
speeds exceeding light (corrected by compressing space) was in one of
The Great Courses; "Introduction to Astrophysics" by Joshua N. Winn
(Princeton Univ.). I would be hard pressed to find that passage there
being 24 lectures but will be on the watch for it. It covers much ground
with a thick mulch of math, so it is hard to digest at first hearing and
I am gradually watching it again.
He seems to know the subject quite well but I thought made too much
of Newton's inverse square law of gravity which really is just High
School math; the area of a sphere being 4pi.r^2; double the radius from
earth's center of gravity and g at the surface is reduced to g/4 at the
2r distance; g/9 at the 3r distance..... His great advance re gravity
was by quantitatively accounting for Kepler's laws and observed orbits
of planets and moons; wonderful and stunning.
On a related matter, is the timing of earthquakes in areas
experiencing high crustal stress, such as the Middle East and India,
correlated with the moon phases and position ? Both regions were
pioneers in Astronomy so I wonder if Astrology started out as a search
for cause and effect re earthquakes.
My impression of the Big Bang is from A Short History of Time
(Stephen Hawking), as I recall, an infinitely small, infinitely dense
singularity which suddenly decided to hatch.
St. Augustine is reputed to have asked the rhetorical question "What
was God doing before he created heaven and earth" and answered that "He
was creating hell for people who ask questions like that".
I can not help but wonder if black holes, apparently universal at
the center of galaxies, are recycle depots where wandering fragments of
matter and energy are drawn in and spit out as new members of the
galaxy.
Science is largely limited to describing the observable. But one
must wonder why and how masses at a distance emit some 'force of
gravity',
YT, DW, Kentville
------ Original Message ------
From: "Stephen Shaw" <srshaw@dal.ca>
To: "naturens@chebucto.ns.ca" <naturens@chebucto.ns.ca>
Sent: 2/21/2019 9:29:32 PM
Subject: Re: [NatureNS] Big Bang ?
>Hi Dave,
>Tough to think about in a simple word-thought framework. Reinforcing Burkhard, from the middle of your post you have re-invented an earlier (1929) then seriously-considered idea that the observed redshift could be attributed to photons losing energy and so increasing in wavelength (getting ‘redder') as they interact with interstellar matter, in a static (non-expanding) universe. Proposed originally by Fritz Zwicky and still occasionally mentioned as a remotely possible alternative to an expanding universe even in recent scientific literature, it’s known sometimes as the tired light hypothesis.
>
>Take a look at the detailed article in Wikipedia “Tired light”. The latter idea predicts for example that the surface brightness of increasingly distant objects can be subjected to the 'Tolman surface brightness test', which it fails, where the relativistic expanding universe hypothesis succeeds. More distant objects should appear increasingly blurred in a static universe where photons are scattered by passing interactions, but this is not observed either. No current observational data accord with it. The article suggests that the idea has been consigned to the dustbin of history by serious astrophysicists and the like.
>Steve
>
>On Feb 21, 2019, at 8:32 PM, Burkhard Plache <burkhardplache@gmail.com> wrote:
>
>> Hi David,
>>
>> the model of the expansion of the universe (Big Bang model) does not
>> rely solely on the red shift of light, but on a number of other
>> observations.
>> See https://en.wikipedia.org/wiki/Big_Bang#Observational_evidence
>> The current model is a consensus, in fair agreement with those
>> observations. (As in any model, there are some hm-hm-s.)
>> Some observations of the universe (horizon, flatness, addressed a bit
>> further down in the wikipedia article) the big bang model does not
>> address or explain.
>> Thus, the model is considered incomplete, or a work in progress.
>>
>> In the past, there have been ideas to 'explain away the expansion of
>> the universe' by postulating light might be losing energy over
>> distance or over time.
>> None of those ideas have survived observational scrutiny, esp. since
>> with those modifications, the other observations do not fit into a
>> larger model.
>> Like too many balls to juggle at the same time. Thus, Occam's Razor
>> favours the redshift.
>>
>> Your suggestion that light might interact with light is generally
>> valid. Such interactions have been seen in experiments, and are in
>> agreement with theory (Quantum Electro Dynamics, to be precise).
>> However, the photon-photon interaction probability is (a) extremely
>> low, and (b) not a way to systematically lower photon energies (due to
>> energy conservation).
>>
>> Your suggestion that 'the most remote sources [...] appear to be
>> receding faster than the speed of light' is simply not correct or a
>> misunderstanding.
>> Not sure where you got that information. Such statements are often
>> repeated, but that does not make them true.
>>
>> You may also want to read the 'Misconceptions' section in the
>> wikipedia article, which addresses your 'In the Beginning' notion.
>>
>> Sorry to shoot down your suggestions.
>> You are not the first one to express such ideas,
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