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PostPosted: Mon Apr 12, 2010 12:34 pm 
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Why do you say magic? There are many discussions in this part of the forum about the evidence for the possible existence of dark matter so there's no point in me going over it again. Nothing is conclusive but the important thing to bear in mind that "dark" simply means unknown. With every statement about the age of the universe come warnings that there are margins of error, assumptions and sometimes plain guesses. No scientist worth their stripes will say that they know for sure. They seem to be more than happy to alter their view if new evidence comes along.

Personally, I am interested in what their ideas are based on current observations. The universe may appear to be 13.7 billion years old according to the information available today or it might in fact be older/younger if we happen to discover some new information. That seems fair enough to me and don't see the point in denegrating hypotheses.

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PostPosted: Mon Apr 12, 2010 5:03 pm 
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In that case it could be regarded as mythology rather than solid science.


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PostPosted: Mon Apr 12, 2010 5:56 pm 
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Err... it bears no resemblance to mythology whatsoever. There is indirect evidence of the existence of dark matter: http://en.wikipedia.org/wiki/Dark_matter.
And even Hubble has "snapped it": http://news.discovery.com/space/hubble- ... atter.html.

It's an hypothesis - science, not myth.

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PostPosted: Mon Apr 12, 2010 9:36 pm 
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joe wrote:
Err... it bears no resemblance to mythology whatsoever. There is indirect evidence of the existence of dark matter: http://en.wikipedia.org/wiki/Dark_matter.
And even Hubble has "snapped it": http://news.discovery.com/space/hubble- ... atter.html.

It's an hypothesis - science, not myth.

Read it before many times and I still have the same opinion. Rather than question the calculations they use or the methodology they adopt, their answer is to add an unknown to the equation. Doesn't make sense to me personally but that is just my opinion.
My opinion is that they got it wrong in the first place and rather than admit that the science doesn't fit anymore they invent dark matter. Our own Solar system is witness to this fact, rather than look for dark matter billions of light years away why don't they look for it in our own Solar system to see if it exists here before making proposterous claims. Surely people don't think that such invisible matter would be selective and not be present much closer to home?
These so called Scientists can't even explain Quantum mechanics or gravity in their own back garden but seem to want to 'hyposthesize' about matter billions of light years away.
I wouldn't call it hyposthesis, i'd call it a mixture of unfounded dribble and fantasy.


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PostPosted: Wed Apr 14, 2010 10:54 am 
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Quasar wrote:
Rather than question the calculations they use or the methodology they adopt,

Yes, of course, they would never do that, they're scientists after all.
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Our own Solar system is witness to this fact, rather than look for dark matter billions of light years away why don't they look for it in our own Solar system to see if it exists here before making proposterous claims. Surely people don't think that such invisible matter would be selective and not be present much closer to home?

Much of the indirect evidence for the existence of dark matter comes from unexpected galaxy rotational curves and gravitational lensing. There's not much of that goes on in our Solar System. Non-baryonic dark matter is quite hard to detect directly but I believe there are a few experimental underground laboratories. Some have even claimed success.
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I wouldn't call it hyposthesis, i'd call it a mixture of unfounded dribble and fantasy

You're entitled.

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PostPosted: Fri Apr 16, 2010 5:51 pm 
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Dear Joe
I am sure there are many aspects of cosmology regarding which I would disagree with Quasar, however I do have simpathy with his suggestion that some of it is a sort of "magic"- one reason why I feel pretty sure humans will never get to the bottom of it.
These days it's very common to use spin off benefits to justify doing things.I will accept that to an extent and even as justifying doing some cosmology but I think there are dangers in trying to go too far (in a similar way that reality TV and celebrity has been, not to mention The Go Jump "Over the Rainbow" competition.
A year or two back I went to a astro society meeting at which a very respectable long standing amateur astronomer announced that cosmologists had (then) deterimined the age of the universe (13.7 billion light years) pretty accurately and certainly to within 5 percent. Only today I was glancing through the current "Discovery" magazine in a shop, it includes an article about some physicists apparently now seriously considering the possibility that the laws of physics may not be constant. I suspect such a possibility could make a nonsense of not just the age of the universe but many aspects of currently accepted conventional cosmology.
Now I am sure that conjecture about the laws of physics possibly varying over time (and\or distance) is nothing new (I have thought about it from time to time over quite a few years myself but always decided that serious professional physicists knew things much better than I do). However, now I am inclined to think otherwise: OK they might be a lot cleverer than me, but are they really any wiser ? (but perhaps they are wiser, after all they get paid for doing it ! Maybe it is true that there's no fool like an old fool).
Best wishes from Cliff( getting all grumpy again!)


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PostPosted: Sat Apr 17, 2010 10:31 am 
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Do the laws of physics really change over time, Cliff, or is it an evolving nature itself that changes, so that the laws have to keep up with it?
People talk about the " laws of nature", as Brian Cox did in his recent TV series, as if the laws actually exist out in nature. This is misleading to the lay-person: nature only knows change.
The laws are, in fact, human constructs: mathematical abbreviations of phenomena to facilitate economy of thinking, in predicting and controlling processes.
No two phenomena are exactly repeatable, so laws are expectations, not exact discriptions, of what actually occurs in practice. If something goes wrong against our expectations, which often happens and with sometimes fatal results, we make "corrections" to the laws. :wink:

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PostPosted: Sun Apr 18, 2010 12:13 pm 
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Cliff wrote:
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Only today I was glancing through the current "Discovery" magazine in a shop, it includes an article about some physicists apparently now seriously considering the possibility that the laws of physics may not be constant

This is interesting Cliff and I mentioned it in a ealier thread in this topic. Scientists are now unsure whether or not time and gravity actually evolved into what we see today. Rather than being a constant like we see today, some Scientists are looking down the road of some fields 'evolving' in some sort of process. This complicates matters somewhat and could have consequences in determining how big and old the Universe is. I wouldn't like to attemp the math involved in such a process. I tend to agree with you that it might be very unlikely that we will ever know the real truth. My understanding of what makes a good Scientist is like so many examples of past Scientists and that is to be able to take solid evidence, work with it and come up with something that is both practical and sensible as far as the rest of us are concerned. In Astro Physics that is not always possible and like Joe explains - leads to a lot of Hypothesis. I would like to add though, that it may be more sensible to collect more data as time goes on and rather than just keep modifying older theories, just store the date for future Scientists to be able to use when things get clearer. I remember reading about when they were working out the DNA double helix in the 40's and 50's, some of the Scientists were jumping the gun on the data collected so far and rather than wait for all the evidence to come in made a fool of themselves. Maybe the Astro Physicists are doing the same thing, jumping the gun before they are 100% certain that all the available data has been collected? Maybe they should just hang fire a while and just observe.


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PostPosted: Mon Apr 19, 2010 1:36 pm 
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Dear Quasar
I think I very much agree.
I am inclined to think (perhaps unfairly) that interesting though cosmology is, there are\or may be, too many people doing it. I might be doing them an injustice but I am think there are too many scientists dabbling about with computer analysis and computer modelling.
Of course I think computer modelling has many uses in many (possibly all areas of science). However, I think nowadays in some respects being able to do computer modelling is considered more important than doing the science itself.
I say that being very much a duck egg using computers - so I am perhaps prejudiced.
However, it seems to me now that some aspects of "modern cosmology" might be better called "mathematical computer modelling cosmology" - no sooner has a new unexplainable observation been done; someone starts a new theory computer model theory trying to explain the observation.
Of course my approach to doing astronomy may be completely stupid, but being an amateur astronomer I think I (and others) have a right to do what we like ( acting reasonably within the law that is - legal not science (though I personally have very little interest in science fiction)
Best wishes from Cliff


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PostPosted: Mon Apr 19, 2010 2:15 pm 
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My view is slightly different in that I do not believe cosmologists ever say that everything they are researching, modeling or whatever they do in their offices and universities, is hard fact. I am quite interested in their hypotheses, even if there is still missing data - educated guesses are even worth listening to. Some of you may not wish to read about current thinking, that's your choice, but it's unfair, in my opinion, to accuse cosmologists and astrophysicists of using "magic" when they do not claim to be 100% correct. If I read Brian Greene's ideas about parallel universes, I don't actually believe there are parallel universes and, strangely, I don't believe he believes it either - not yet anyway - because there isn't enough evidence.

I agree that good science is based on observation. There is an obvious problem with cosmology in that observations are very difficult and/or expensive, hence the need for computer modeling.

I don't know why too many people doing it can be regarded as a problem. Do smaller numbers mean better results?

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PostPosted: Mon Apr 19, 2010 6:00 pm 
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Joe wrote:
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If I read Brian Greene's ideas about parallel universes, I don't actually believe there are parallel universes and, strangely, I don't believe he believes it either - not yet anyway - because there isn't enough evidence.

From my understanding of the Quantum field of late I am getting the feeling that there is something parallel going on. Whether you can describe what goes on as being a parallel Universe is open to debate but there are definately observable parallels happening within the Quantum field.
My feeling is however, what we observe going on cound actually stretch to an infinite amount of possibilities all parallel with one another within the same time frames. Each possibility though, has the potential to cancel the rest out. So in essence you have an infinite number of parallel possibilities all with potential, when I say parallel I mean within the same time frame. For example, an orbitting Electron has the potential to be anywhere depending on circumstances or where and how it is observed. The question is though, are potentials within the same time frames the same as parallels within the same time frame?


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PostPosted: Tue Apr 20, 2010 11:01 am 
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Quasar wrote:
From my understanding of the Quantum field of late I am getting the feeling that there is something parallel going on.

Parallel universes are certainly intriguing. Can you elaborate on "getting the feeling"?

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PostPosted: Tue Apr 20, 2010 4:45 pm 
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joe wrote:
Quasar wrote:
From my understanding of the Quantum field of late I am getting the feeling that there is something parallel going on.

Parallel universes are certainly intriguing. Can you elaborate on "getting the feeling"?

Because the more we observe the goings on within the Quantum field the more instances of different potentials arrise. Like I said, those potentials are or could be described as parallel sequences within the same time frame. Each parallel has the potential to cancel the others out but only when observed. So really we have parallel sets of conflicting data up until the time of observation. If they are never observed then those parallel sequences will remain. They have to be described as parallel because they are all within the same time frame, technically happening simulataneously but not at all. To be honest Joe it is confusing stuff and I don't know if parallel is the correct word to describe it. It is described as a wave of probabilty, a wave of possibility or a wave of potential, either way it seems to me to have parallel charactaristics.


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PostPosted: Tue Apr 20, 2010 5:04 pm 
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Just a little addition to that and a sort of flip side to that coin. Looking at the energy involved in the Quantum field processes, if we have parallel sequences all with potential to cancel the rest out then we come to a cross roads. We come to a point where we have to ask the energy question which is 'what happens to the energy field contained within the cancelled out potentials?'
Does it become dark energy? Another question would be 'what would happen if we started cross referencing potentials and observers so that one negative potential in one argument becomes a positive potential in another argument'?. Mind boggling stuff.


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PostPosted: Fri Apr 23, 2010 5:57 pm 
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Dear al(L)
I personally find Cosmology an interesting subject. However as far as I am concerned cosmology is only one of many interesting subjects making up astronomy. The beauty of being amateur astronomers is we can get involved in whichever subjects\parts of astronomy that we want to. However, I think in the main Cosmology is a field dominated by "professionals". I doubt if nowadays there are many amateur astronomer cosmologists who professional cosmologists would take seriously.
Unfortunately , I now don't take professional cosmologists very seriously because they seem to come up with numerous theories\ideas\hypothesis, which might be theoretically viable (eg mathematically) but that doesn't necessarily make them correct (eg because parameters used may not be valid).
In my opinion allowing people (ie paying them) to specialise in cosmology may be a mistake. The answer might be for cosmology to be limited to being just a spin off from ordinary general astronomy.
Best wishes from Cliff
Best wishes from Cliff


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