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#39238 - 07/30/11 05:56 PM Re: Light From Distant Galaxies. [Re: Orac]
Bill S. Offline
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I am trying to ignore any previous knowledge/ideas I might have had about cosmology, and form an opinion based only on the arguments put forward in this specific exchange. So far, I am still on the fence. Don’t stop now!
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#39244 - 07/31/11 10:55 AM Re: Light From Distant Galaxies. [Re: Bill S.]
redewenur Offline
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Originally Posted By: Bill S.
I am trying to ignore any previous knowledge/ideas I might have had about cosmology, and form an opinion based only on the arguments put forward in this specific exchange. So far, I am still on the fence. Don’t stop now!
Ignore what you already know? Some would indeed be gratified. To "form an opinion based only on the arguments put forward in this specific exchange" would be, to put it mildly, unreasonable. So unreasonable, in fact, that I'm sure that's not what you meant. There's a whole universe of research results out there.
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#39249 - 08/01/11 12:08 AM Re: Light From Distant Galaxies. [Re: redewenur]
Bill S. Offline
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Quote:
I'm sure that's not what you meant.


You are absolutely right, of course. I was talking only in terms of seeing if either Bill 6 or Orac could present a case that would persuade me either way, if that were the only information I had.
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#39251 - 08/01/11 02:53 AM Re: Light From Distant Galaxies. [Re: Bill S.]
Orac Offline
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I can't make a case for anything ... they all have holes as far as I can see.

I am pretty much doing the same Bill S because the science is moving so fast.

Did you read the article I posted on space manifolds I actually found it fascinating to think about. We rarely think about the shape of the universe but it may tell us alot and there are some intriguing possibilities.

I mean it doesn't matter what theory you belive from creationism to big bang, inflation or a mirriad of others what shape is the universe.

I will organize a post with some interesting problems I can see for tomorrow.

Edit: I should give you some light reading on what the reporting season from the LHC has seen
http://www.math.columbia.edu/~woit/wordpress/?p=3864
http://www.science20.com/quantum_diaries_survivor/new_susy_fits_post1fb_lhc_data-81223

Thats a whole lot of theories dead and buried including my old string theory one which I was backing :-(

I highlight the big thing

Quote:

The bottom line is much stronger results ruling out supersymmetry, extra dimensions, black holes and other exotica, restriction of the possible mass range of the Higgs to about 114-150 GeV, and a tantalizingly small and not yet statistically significant excess of possible Higgs events in the mass range 120-145 GeV.


That means we are loooking at a light higgs model or a higgless model and most exotic models are out the window.




Edited by Orac (08/01/11 03:08 AM)
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#39265 - 08/02/11 03:03 AM Re: Light From Distant Galaxies. [Re: Orac]
Orac Offline
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To Bill 6:

Been kicking some thoughts on tired light around, I do like its simplicity but still struggling with a mechanism to make if fit all experimental observations.

Saw this article:

http://www.physorg.com/news/2011-08-manipulating-light-at-will.html

Thats details of the study of light through meta material where they can play havoc with the light while in the media.

One of the key findings .. which is the observation that is causing me problems believing tired light.

Quote:

When light passes through a material, even though it may be reflected, refracted or weakened along the way, it is still the same light coming out. This is known as linearity.


Now I note they can get a frequency shift by amplifying harmoics

Quote:

"For highly intense light, however, certain 'nonlinear' materials violate this rule of thumb, converting the incoming energy into a brand new beam of light at twice the original frequency, called the second-harmonic,"


To get a tired light redshift we would need to amplify the lower harmonic essentially halving the frequency.

I am not sure but my guess would be we are going to see too much redshift from a typical sun. Of coarse we really only have our sun to calibrate spectra against so there is some wiggle room here I suspect.

Going to go and look at what happens to spectra lines with harmonic amplification that may kill this line of thought but at least I have found a way to get redshift without defying Quantum mechanics so we have hope.
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#39281 - 08/03/11 09:16 AM Re: Light From Distant Galaxies. [Re: Orac]
Orac Offline
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More playing around with tired light theory:

Okay if we take Raman scattering (http://en.wikipedia.org/wiki/Raman_scattering) we essentially have the basics of physics we need for tired light.

Now we need to put Raman on steroids so we don't get approximately 1 in 10 million photons we need almost all do it so it matches our observation.

My initial thought was to argue well the light has come a long way so perhaps it just tells us no photon can get to us without undergoing such a transition because chances are it encounters such a transition on the way.

My problem with this conjecture is we have galaxies which are the same distance away with vastly different redshifts. This leads us to a sticky problem of then trying to make space paths from these galaxies not homogenous.

This is essentially one of the same arguements used to dismiss tired light as quoted by Halton Arp

Quote:

Over the years, many people have argued that photons lose energy on their long voyage through space. This is an entirely reasonable idea, since the distances are the largest we have experience with. But there are several observational arguments that persuade me that this is not an important part of cosmic redshifts:

The first is that as we look to lower galactic latitudes in our own galaxy, we see objects through an increasing density of gas and dust until they are almost totally obscured. No increase of redshift has ever been demonstrated for objects seen through this increased amount of material. Secondly, we have seen that if we look through extragalactic space, the example of quasars linked to low-redshift galaxies demonstrates that two objects at the same distance with closely the same path length can have vastly different redshifts.

Finally, if we say there are clouds of a redshifting medium around each individual object, then there should be gradients of redshift across resolved objects, which are not observed. Further, we should see silhouetting effects between adjacent objects, which also are not observed. Perhaps on some level, light can get tired, but it does not appear to be significant in the redshifts we are dealing with.


My next thoughts were in reading on Raman scattering that there is very big differences between Raman scattering and fluorescence. That leads you into a big distinction in that Raman scattering is a coherent process, whereas fluorescence is not. That lead me into Raman Spectroscopy (http://en.wikipedia.org/wiki/Raman_spectroscopy)

This is where I ran into real trouble because the Hubble telescope is very very sensitive. My next problem is the hubble data has been analysed for Raman Spectrum lines as well as doppler redshift.

First jupiter
(http://www.lpl.arizona.edu/~yelle/eprints/Betremieux99a.pdf)
then followed by Venus, Jupiter, Saturn and Uranus.

This shows they can isolate an see the two effects on top of the same data.

Now I really am getting stuck.


Thoughts anyone .... or have I reached the end ???
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Edited by Orac (08/03/11 09:18 AM)
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#39282 - 08/03/11 02:02 PM Re: Light From Distant Galaxies. [Re: Orac]
Bill Offline
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Registered: 12/31/10
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Loc: Oklahoma, USA
Orac,

I think you have reached an end. When Zwicky developed the hypothesis, right after Hubble observed the red shift for distant galaxies, He himself shot down several possible mechanisms. Since then astronomical measurements have gotten more and more precise. And every one of the possible explanations for how tired light could occur have gotten more and more unlikely. I suppose that there might be some strange effect that hasn't been considered, but there have been a lot of people who have looked into it and they have found no data supporting the hypothesis.

Bill Gill
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#39292 - 08/04/11 04:43 PM Re: Light From Distant Galaxies. [Re: Bill]
Bill S. Offline
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Registered: 08/20/10
Posts: 3570
Loc: Essex, UK
One thing that seems typical of science in general, and cosmology in particular, is that however good the arguments seem to be for a particular viewpoint, there is always room for an alternative interpretation.

I'm getting a bit out of my depth, so I look forward to a good counter from Bill 6, and hope I can understand it. smile
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#39295 - 08/04/11 05:56 PM Re: Light From Distant Galaxies. [Re: Bill S.]
redewenur Offline
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Registered: 02/14/07
Posts: 1840
Originally Posted By: Bill S.
One thing that seems typical of science in general, and cosmology in particular, is that however good the arguments seem to be for a particular viewpoint, there is always room for an alternative interpretation.

To greater and lesser extents, yes, but sometimes perhaps not at all. The natural selection process in evolution is one topical example. But, re the standard model of cosmology, any cosmologist/astrophysicist will agree that there's room for a great deal of modification.

If anyone here hasn't read The Fifth Essence by Lawrence Krauss, I'd recommend it, even though it's 35yrs old and he'd have to make some revisions if he rewrote it. It's broadly about Dark Matter, but the information and explanations re evolution of an expanding cosmos from the Big Bang are very clearly delivered, and continue to be supported as new data comes in.

Disagreeing with it all only because one doesn't like it will leave a scientist unmoved.

http://www.youtube.com/watch?v=iMDTcMD6pOw&feature=player_detailpage
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#39306 - 08/05/11 03:54 AM Re: Light From Distant Galaxies. [Re: redewenur]
Orac Offline
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Registered: 05/20/11
Posts: 2819
Loc: Currently Illinois, USA
I think I would agree 100% with redewenur I dislike the results science is throwing at me I would like them to be simpler but the results speak for themself and it isn't like that and I just have to accept it.

18 months ago I was confident SUSY would be seen by the LHC and alot of mysteries would be solved. My venturing into QM studies 9 months ago rocked my conviction and here we stand today about to read the last rites to SUSY some have already done so.
(http://www.math.columbia.edu/~woit/wordpress/?p=3864)

I would have liked SUSY to be true it would make understanding easier but you have to face the realities of observations and I simply have run out of wiggle room to explaining them.
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I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.

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#39307 - 08/05/11 03:55 AM Re: Light From Distant Galaxies. [Re: Bill S.]
Bill 6 Offline
Member

Registered: 02/28/11
Posts: 74
Loc: Australia
I have no more to say in relation to the tired light concept.

The big bang theory is awe-inspiring compared with a ‘mundane’ universe of infinite time and space. It is a basis for more books and articles and is applied in order to ‘justify’ multi-billion dollar research projects thus will continue to remain the preferred theory amongst physicists until disproven.

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