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PostPosted: Thu Sep 09, 2010 2:07 pm 
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Strikes me that is the study is confirmed it's findings have some very very significant impacts on many of the fundamental assumptions of cosmology.

My summary of the work is that the fine structure constant appears to vary across the Universe - so the further you move from Earth the more alpha has changed.

As it is pretty important then maybe our locality is only a (relatively) small area where the physical constants are suitable for life.

Plus, if alpha changes then why not other constants ?

http://www.sciencedaily.com/releases/2010/09/100909004112.htm

And maybe Scotty was wrong when he observed "Ye canoot change the laws of physics"

Ian


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PostPosted: Sat Sep 11, 2010 2:34 pm 
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Dear Ian (Deimos)
I can only speak as a very ordinary layman on these DEEP-DEEP cosmological matters.
I did have vague hopes that I might get a grasp of "real" Relativity occasionally in the past but eventually threw in the towel. I now just read about such issues at a fun level.
However, that is not to say I don't enjoy myself pontificating about cosmology from time to time.
Recently I've been getting more and more sceptical about some supposed advances in modern cosmology and possibly particle physics (another field I don't have much understanding of).
However, I sometimes think we\they are advancing too rapidly.
As far as i am concerned whether it is infinite in size or not, the\our universe is pretty BIG (to say the least) so I would be quite happy to accept the possibility that some of the Laws of Physics are more flexible than some think.
I was\am quite happy to think MOND theory is OK - not necessarily a complete whole answer but a useful approximation.
I sometimes think these days there is possibly too much reliance on computer technology.
To be fair I suppose cosmologists might be cleverer than tax collectors.
But whilst there seems to be an almost unbelievable belief in cosmological computer simulations, when it comes to tax the computer doesn't always get it right.
Best of luck from Cliff


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PostPosted: Sat Sep 11, 2010 8:51 pm 
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I suppose what makes this discovery so important (though it is still being subjected to peer review and still confirmation from others, etc.) is that as I understand it one of the major assumptions in cosmology is that the Universe is homogeneous. This would make that assumption wrong - though I do not know enough as to how much cosmological theory would become invalid.

I have often seen it said that the physical constants in our universe make is possible for life to exist but that other universes probably have same laws but different constants and that would make then unsuited to life. However, if different physical constants makes the location unsuited to life then this discovery could mean that only our locality would be suited to life (obviously we would have to be within such a region). Whilst the fine-structure constant does not vary massively in the measures regions to would appear it changes which could have important implications.

I found it quite a surprising discovers - partly because it often strikes me how quite a lot of cosmology rests on assumptions and as such risks the "house of cards" problems were those assumptions to be suspect - and maybe this is it.

Of course it is good news because it means we are learning and may have to adapt our models but it is all progress.

Ian


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PostPosted: Sun Sep 12, 2010 8:43 am 
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Deimos wrote:
Strikes me that is the study is confirmed it's findings have some very very significant impacts on many of the fundamental assumptions of cosmology.


I see that the cosmological "constants" were discussed at the Joint European and National Astronomy Meeting 2010 in Lisbon, Portugal.

Reading the abstracts, it appears there were several presentations in relation to alpha, which presented different views of the constant nature of the "constant". I think that the Science Daily article could have been more balanced and presented both sides of the debate.

Quote:
Varying Fundamental Constants from Big Bang to Atomic Clocks
V.V. Flambaum (UNSW)
I present a review of works devoted to the variation of the fine structure constant , strong interaction and fundamental masses (Higgs vacuum). There are some hints for the variation in quasar absorption spectra and Big Bang nucleosynthesis data. A very promising method to search for the variation consists in comparison of different atomic clocks. Huge enhancement of the variation effects happens in transitions between very close atomic, nuclear and molecular energy levels. Large enhancement also happens in nuclear, atomic and molecular collisions near resonances. How changing physical constants may occur? Light scalar fields very naturally appear in modern cosmological models, affecting parameters of the Standard Model (e.g. ). Cosmological variations of these scalar fields should occur because of drastic changes of matter composition in Universe: the latest such event is rather recent (about 5 billion years ago), from matter to dark energy domination. Massive bodies can also affect physical constants.

New Analysis of a Large Sample of VLT Quasar Spectra for Varying Fine structure Constant
J. Webb (UNSW)
Previous observations of quasar spectra from the Keck telescope suggested a time variation of the fine structure constant. We have now completed a new study using a large sample of quasar spectra from the VLT. When the new VLT data are combined with the previous Keck sample, a consistency emerges within the data itself, concordant with the earlier Keck result, and in addition revealing a statistically significant signal for a dipole-type spatial dependence.

The Value of the Fine-structure Constant over Cosmological Times
C. Gutierrez (IAC)
The optical spectra of objects classified as QSOs in the SDSS catalogues are analyzed with the aim of determining the value of the fine structure constant in the past and then check for possible changes in such constant over cosmological timescales. The analysis is done by measuring the position of the fine structure lines of the [OIII] doublet in QSO nebular emission. A value of [technical details removed - read the original abstract for the details DGE] (up to redshift z=0.8 ) was determined. The use of a larger number of spectra allows a factor 5 improvement on previous constraints based on the same method. On the whole, we find no evidence of changes in on such cosmological timescales....


The programme indicates they went on to review the other cosmological constants too.

Quote:
Rodger Thompson (Steward Obs.) : Current State of Mu Measurements Versus Cosmic Time
Martin Wendt (Hamburg) : Robust Limit on a Varying Proton-to-electron Mass Ratio from a Single H2 System
Wim Ubachs (Amsterdam) : On the Variation of the Proton-to-electron Mass Ratio

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PostPosted: Sun Sep 12, 2010 10:00 am 
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david entwistle wrote:
I think that the Science Daily article could have been more balanced and presented both sides of the debate.


But the Science Daily report was NOT a review of the current debate but a report on a particular piece of work !! you have to read an article for what i is NOT what you might want it to be.

Ian


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PostPosted: Mon Sep 13, 2010 12:25 pm 
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Dear Ian and David
As I've already said, my knowledge of cosmology is limited (and probably biased) so in some respects perhaps I should stay out of the discussion. However, I do find cosmology generally an interesting subject, so I hope you won't mind me joining in from time to time.
Best wishes from Cliff


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PostPosted: Mon Sep 13, 2010 1:27 pm 
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Cliff wrote:
Dear Ian and David
As I've already said, my knowledge of cosmology is limited (and probably biased) so in some respects perhaps I should stay out of the discussion. However, I do find cosmology generally an interesting subject, so I hope you won't mind me joining in from time to time.
Best wishes from Cliff


I'm my own opinion it is questions, opinions and discussions that make a forum what it is so ask and discuss away - it is what is needed here (in my opinion).

It can get difficult when a forum becomes more of a reference source as people do tend to feel intimidated and become less active and forums then start to decline and die (I have seen it happen on other forums).

I think a forum is for people to say "I think ..." and others to say "but ... so maybe ..." and for people to discuss things. Post away and join in (everybody).

Ian


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PostPosted: Thu Sep 16, 2010 8:22 pm 
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Dear Ian
I'll continue to plug at it from time to time - hoping I don't bang my cosmology drum excessively monotomously loudly.
Best wishes from Cliff


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PostPosted: Sat Sep 18, 2010 9:22 am 
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Unless we are competent mathematicians with plenty of scientific data to draw on, there doesn't seem much point in discussing cosmology and astrophysics.
I've started several threads in this forum, but only to draw attention to snippets of information I've gleaned from the science journals and the press in general.

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PostPosted: Sat Sep 18, 2010 10:06 am 
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There are yards of bookshelves in Popular Science Sections in Waterstones, etc. devoted to cosmology and astrophysics that manage to explain quite complicated ideas without the use of mathematics - or at least very little. I don't see why we can't discuss them here in the same way.

I agree that we would understand more if we were competent mathematicians or competent mathematicians translated the ideas to those of us who are more challenged but I still see the Astrophysics Section here in the forum as very useful.

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PostPosted: Sun Sep 19, 2010 4:15 pm 
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Dear al(L)
There are some aspects of what I think of as basic astrophysics that I feel quite comfortable with.
However, there are other aspects of "serious" astrophysics I feel out of my depth. Half of me being disappointed at my inadequacy in not understanding it, my other half thinking that understanding it isn't important anyway. But sometimes all of me thinking "cosmologists" might have got some things wrong.
I am a retired bog standard engineer. Going back to the 1960's I recall a hiatus in engineering. Arguably it was all way above my head.
Amongst other things a high up structural engineer (Kerensky) apparently reckonned there were some elite engineers way above the rest. Those elite were so brilliant they shouldn't be bound by such things as "British Standards".
Soon after that there were big problems with several then new bridges that super engineer was involved with.
Best of luck from Cliff


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PostPosted: Tue Sep 21, 2010 9:10 am 
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As you point out, Cliff, even the experts don't always get it right. Even so, I'm sure you'll agree that, when it comes to astrophysics, the experts with data to draw on, are more likely to get it right than we non-experts are.
As Mike Feist once said, when it comes to the technical aspects of astrophysics, we non-experts can only engage in "jolly banter".
If someone comes onto the forum and types in, "I had a hunch in bed this morning that the universe is so-and-so", should we regard this as serious science?

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PostPosted: Tue Sep 21, 2010 9:57 am 
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Cliff wrote:
There are some aspects of what I think of as basic astrophysics that I feel quite comfortable with.
However, there are other aspects of "serious" astrophysics I feel out of my depth. Half of me being disappointed at my inadequacy in not understanding it, my other half thinking that understanding it isn't important anyway. But sometimes all of me thinking "cosmologists" might have got some things wrong.

I probably share all of those feelings, Cliff. However, it's still an interesting subject, is it not?


Brian wrote:
As Mike Feist once said, when it comes to the technical aspects of astrophysics, we non-experts can only engage in "jolly banter".

If by "jolly banter", Mike means non-expert opinion, then yes, although there are amongst us a few very knowledgable people, even real astrophysicists. I thought forums were all about questions, answers, discussion and jolly banter!?

I notice that Mike rarely comes to the Astrophysics section to engage in jolly banter, probably because he believes cosmology to be dead in the water.
Mike Feist wrote:
In my personal opinion cosmology is dead in the water!! Floating, lost in a vast unfathomable sea of unproven and unproveable, and conflicting theories, with real answers beyond the abilities of man to comprehend

Which, with all due respect to Mike, is nonsense of course. :wink:


Brian wrote:
If someone comes onto the forum and types in, "I had a hunch in bed this morning that the universe is so-and-so", should we regard this as serious science?

Well, I don't and I don't think anyone else should. I would presume that the person posting would not consider it so either (although there have been a few who might argue)! The forum is open, and everyone is welcome to comment on or ignore posts - or whole sections if they desire.

But I suppose this is wandering off topic... :wink:

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PostPosted: Tue Sep 21, 2010 4:05 pm 
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Dear Joe et al
I suppose to be strictly correct you are right in saying you\we may be wandering off topic (ie "alpha").
However, in some respects the wandering is as far as I am concerned often just as interesting as the strict topic we should be talking about.
However, I'm afraid I do find myself sympathetic to many of Mike's views.
Perhaps slightly differently to Mike I certaily think of cosmology is very interesting but I personally think the "experts" need to take a step or two back and perhaps not take cosmology too seriously - give or take a few branes here or there.
I certainly do not share Brian's faith in experts.
With regards "experts" many years ago my old "chief" told me a tale about one of his experiences in WW2.
He was a Scotsman in the RAF for a time posted to remote airfields in the North West Highlands. Apparently a Hebridean born RAF sargeant was very concerned about the vulnerability of the many aircraft hangers on the wild remote islands. He actually officially contacted the Air Ministry\MOD expressing his concerns and strongly suggested the open hangers should be fitted with solid tight doors to reduce the risk of wind damage.
The RAF "experts" rubbished the sargeants suggestion. A few months later there were some strong winds which wrecked several hangers and did some aircraft no good - let's say it saved the Luftwaffe a lot of petrol (Catch 22).
Apparently soon after that the RAF built new Hebridean hangers and repaired surviving old ones with doors !
One of my problems with cosmologists is that even if they get things wrong there are not usually much in the way of serious consequences for them to worry about.
Best wishes from Cliff


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PostPosted: Wed Sep 22, 2010 1:58 pm 
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Hold on, Cliff! I didn't claim that the experts are always right - only that they are likely to get it right for more of the time than we non-experts are.
If you had tooth-ache, would you go to a dentist or a florist?

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