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You're right - just plain "valid" isn't good enough wording. |
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I think "the first explanation the mainstream latched onto and they stubbornly refuse to seriously consider other alternatives" is a better discription of the current situation.
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jwj It's a big universe out there...is it really unwinding, really burning out? |
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At the end of page 9 and beginning of page 10 it seemed this thread was beginning to achieve some focus.
Worm hunter: OK, Soup, what exactly about DM/DE do you find unfalsifiable? http://www.badastronomy.com/phpBB/vi...=299767#299767 Xbalanque: And that's really the whole point of this, isn't it? Thanks for getting it back on track. http://www.badastronomy.com/phpBB/vi...=299821#299821 jaydeehess: Pains me to say it since I was so snarky before but I agree with soupdragon. DM/DE is not a theory, it is a patch. http://www.badastronomy.com/phpBB/vi...=299824#299824 And I tried to pin down the DM and DE proponents by getting them to clarify their positions. http://www.badastronomy.com/phpBB/vi...=299969#299969 Quote:
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Let's not lose sight of that.
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"A witty saying proves nothing" Voltaire. "All your bias are belong to us" Ara Pacis. |
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OK, Soupdragon2, you say that DM/DE add subjectivity. But you dont give examples of what you find subjective about them. I understand that at one point they were patches if you will, but i think we have moved past that stage through thte use of predictions and testing of atleast the observable effects on the universe. Unless you have a reason to think that the tests were improperly done or unfalsifiable to begin with, why do you still think that they are unfalsifiable. Sorry if I am just missing it here but i have yet to see you actually apply Poppers definition to either DM/DE, but only state it.
What i have learned from this thread so far: A theory/auxilary hypothesis must make testable predictions in which it is possible for the said theory/auxiliary hypothesis to fail. Seems pretty logical to me. But DM/DE has been showin to make testable predictions which they could of failed. At this point I am going to rephrase my question a bit: If you dissagree with the tests of DM/DE then can you point out why? Quote:
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They call 'em fingers, but i've never seen em fing..... oh there they go!! otto |
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However, I think that some people are trying to claim DM and DE as theories in their own right? Quote:
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Dark matter halos
I have been trying to remember where i read this article for awhile now and i finally found it. to me it is another example of DM making falsifiable predictions, hence being falsifiable.
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They call 'em fingers, but i've never seen em fing..... oh there they go!! otto |
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Tell us exactly why you consider DM/DE, black holes, BBT(?), gravitons, and quarks (anything else?) to not be falsifiable. Quote:
To answer your question, yes, I will stipulate to all 3 of those points. Like I said, I have small issues with them, but those issues aren't really relevant here. I'll stipulate for the purpose of moving on to the meat of the discussion. Quote:
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Since precise measurements of the effect of gravity over large but local scales shows no signs of any increase whatsoever (beyond what newtonian and einsteinian gravitational theories predict), then explanation (2) would appear to be highly unlikely, which fits well with the general feeling that such an explanation is ludicrous. The gravitational constant g has always been thought to be constant, and local observations consistently verify this. Numerous variable-g theories have been falsified, and the popular MOND theory has recently had a stake driven through its heart. So explanation (1) appears the likely candidate, and searches are on to verify it. The fact remains: there must be some explanation for these observed galactic dynamics. Nobody's absolutely sure about what that explanation is. Explanation (1) is pretty simple and straightforward. Do you have another explanation that is coherent, consistent, and complete? (and why hasn't it been published?) Quote:
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Everyone is entitled to his own opinion, but not his own facts. |
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Whew! That was a long read!
I'll chime in on the "are DM/DE theories?" question. I would argue that DM/DE are not falsifiable, because they are themselves falsifications. You don't falsify falsifications, you have to prove that the test that led to the falsification was an invalid test. The standing theory before DM was "All matter in the universe that interacts with gravity, interacts with light also." DM derives from a test that falsified this theory, so you have, "There is matter which interacts with gravity, but not with light. There may be individual theories about the nature of dark matter, which are themselves falsifiable, but to get rid of DM, you have to attack the test(s) of the "bright matter only" theory, and show they weren't valid. Quote:
Is psycoanalysis subjective because different researchers can look at the same results and interpret them differently within the framework of the same theory. If a theory becomes partially subjective, are there some observations that must be explained the same way, and others that may be interpreted in different ways? How has DM/DE done this to gravity, or whatever theory they are AHs of? |
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Mathematically, MOND provides the best model for the edgy stuff but fails in the second case. On the other hand, textbook newtownian stuff fills the galactic cluster voids, but the 'cusping' features necessary to model the MOND effects require unrealistic parameters and selective interactions. Because of these observations, in my opinion, they are caused by competely different phenomenon. Quote:
But to even be published, alternatives must be very close fits to the current cosmology. In THIS environment, it is impossible to weigh alternative answers fairly. The Eriksen paper I started a thread around is a good example: The results of the study are certainly at odds to some degree with the current interpretation of the CMB, but in their conclusion, they state just the opposite. Would it have been accepted for publication if they had stated otherwise? Probably. Would they lose credibility for doing so? Maybe - many have. Another example is a paper pointing out Two-point compressions are completely at odds with supernova Ia interpretations. The authors conclude the two-point compressions are flawed without even weighing into the discussion to possiblity the supernova interpretations may be biased. Since the two point statistical studies are based on thousands of galaxies, and supernova models on a handful of data points, this is disconcerting. There was also a very technical paper last week that pointed out as soon as you assume the universe is 70 dark energy, all subsequent calculations are biased by this assumption, and the error margins are diminshed or become convergent, creating more confidence than is justified in the current model. I think I have demonstrated in my preprint similar biases caused by assumptive use of the current relativistic distance modulus, and compete dismissal of the tensors of polarization as a necessary factor in the calculation cosmic redshift distances - could cause the same false security in the current interpretation of supernova light curves. Quote:
Even more fundamentally, there should not be just one acceptable model: Heisenberg should trump Einstein and Newton, there may be more than one scientifically valid explanation for everything we see in the past, and so individual studies should be evaluated on the bases of the physical realities incorporated in the solution, and not, at least initially upon whether or not they fit into the current big picture. The plasma dudes have put together an alternative cosmology that, in my opinion, is just as flawed as the consensus cosmology. Somewhere in-between or just outside the established parameter window there may be a better solution.
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jwj It's a big universe out there...is it really unwinding, really burning out? |
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A brief recap
Falsifiability Much of this thread has dealt with confusion over the meaning of the term Falsifiable. Many people seemed to think that a theory is falsifiable if it might be proved wrong at some point in the future. This is not the case. For a theory to be falsifiable it must be testable now*, and the test must be vulnerable to be being proved false, that is, falsified. In other words, there must be some conceivable way in which the theory can be refuted, otherwise the results of any experiment can be interpreted in such a way as to support the theory. It is important to recognise that this methodology was formulated by Karl Popper, and that he proposed Falsificationism as a tool for demarcating between science and non-science. In this context the terms testable and falsifiable are hereafter synonymous. * It might be argued that a test might be developed at some point in the future, but caution is recommended here, as NO guarantees can be made that these tests -- if and when they come about -- will be workable. Auxiliary Hypotheses If we discover a problem with a theory, it is not automatically abandoned. It can be rescued by an Auxiliary Hypothesis, but these are subject to strict rules. For an AH to be valid it must make a theory more testable/falsifiable. In other words it should improve its informative content, and not just patch a leak with hypotheses that are not testable. These would be kludges! Progress so far DM/DE For the sake of simplicity this thread has concentrated on Dark Matter and Dark Energy. I will be happy to look at other theories later, but for the time being we seem to have agreed that this thread needs some focus. Do DM and DE qualify as Auxiliary Hypotheses? We also agree that DM and DE are not theories in their own right, but were intended to address problems relating to existing theories, principally gravitational in nature. On this basis I will examine claims made by DM and DE proponents in respect of their validity. Do they fit the strict criteria necessary to be considered auxiliary hypotheses, or are they, in effect, kludges? Background Dark Matter, of course, was hypothesised to account for the 'missing mass' problem, while Dark Energy is hypothesised to be driving the expansion of the universe, alleged to be accelerating. Differing viewpoints ascribe varying importance to DM and/or DE. Either way, they are not directly observable. Observations did not match expectations, and their existence was inferred to account for this discrepancy. In other words their existence rests on an interpretation of contradictory data. While this does not in itself invalidate them, it provides a valuable insight into the reasons for their conception. Quote:
They have not been dectected in any laboratory style experiment. It is accepted that much of cosmology and astronomy is based on observation of distant phenomena, but both DM and DE, if they exist, are generally considered to be widely distributed. DM is generally assumed to constitute no less than 70% of it! More recently it has been proposed that DM might hang-out in clusters and at the edge of galaxies, but this simply makes it more elusive. Quote:
In another recent development, for example, it has been proposed that DM and DE maybe the same thing. Please bid welcome to Scalar fields! Dark Matter and Dark Energy: One and the Same? http://www.space.com/scienceastronom...ay_040712.html If we go on like this, DM and DE seem to be safe for some time in the future. As they continue to evolve with ever more exotic properties and behaviours, it becomes increasingly difficult to test for them. Quote:
It has been argued that we are looking through the distorted window of the Big Bang. This infers that many theories have been designed to conform with BB ideas. If there was no initial explosion, and if the universe is not expanding (accelerative or otherwise), then the necessity for the existence of DM/DE is lessened. I accept that while there is much conflation here, differing theories are not necessarily dependent... While I do not wish to discuss the BBT in any great depth, my point is relevant to the following. Alternatives The speculative nature of DM and DE is further underlined when we consider that there are other viable alternatives that can explain the discrepancy in our observations. Why is it that DM and DE are considered more acceptable to the mainstream? Is it because they fit more neatly with the BBT? While this is almost certainly the case, it does not make DM and DE falsifiable! They remain merely prefential to the mainstream, and there is no compelling evidence to justify this preference! Preferential does not equate to falsifiable! OK, MOND has suffered one or two blows just lately, but there are other credible theories. As dgruss23 has pointed out, there are many candidates that may explain the flat rotation curves of spiral galaxies. Wimps, Axions, Machos... He has also offered his opinion, in a number of other threads, that Baryonic dark matter is the strongest candidate for explaining galaxy rotation curves. And also that in galaxy clusters it is not dark matter causing the high velocity dispersions, but rather intrinsic redshifts. Thus cluster dark-matter estimates are too high. But if the dark matter is baryonic then we can probably say bye-bye to the Big Bang because this would contradict BBT nucleosynthesis. Conclusion I believe that any of the above points, when taken alone, do serious harm to any notion of DM and DE being considered falsifiable. Even if you disagree with any of them in isolation, when taken cumulatively I believe they represent a powerful argument against any such claim. The only possible basis by which DM and DE might be considered falsifiable relates the the claim that they make predictions that can be falsified. However, as we have seen, these predictions have been continually kludged with further subjectivity, and reasonable alternatives exist. They cannot, therefore, be considered Auxiliary Hypotheses! Quote:
The survival of DM and DE up until now actually seems to have relied on our inability to test for them, thus contradicting the most the most basic principle of Falsifiability. In summation, DM and DE are not testatable in terms of even the most cursory application of Karl Popper's methodology. They are NOT falsifiable! Further... Quote:
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As ever, you miss the point, and try and sidetrack the real issues! Are you Kilopi in disguise?
I construct arguments that are consistent and cumulative, and you offer opinions as if they are facts. Quote:
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I consider this erroneous constraint to be the principal reason why you consider many scientific theories to not be falsifiable (and therefore not scientific). |
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jwj It's a big universe out there...is it really unwinding, really burning out? |
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Soup, sorry if i missed something but i have yet to see you make an actual argument about a DM/DE showing that they add subjectivity to any theory. This seems like an important thing to do if you want this thread to go anywhere. Atleast to me that is. I think i have been asking this question since around page nine, possibly even before that, so here it goes again, this time will be the last for real this time. I dont feel like going around in circles again on this issue. To me it is one of the major parts of your statement so: What exactly do you find unfalsifiable about DM/DE?????
If you think it adds subjectivity show where please. I dissagree with your assertions that inorder for a theory to be falsifiable they must be testable today. If we could test them the day they were concieved they would have been concieved the day before, and so on and so forth. Science cant work this way as it would never accomplish anything. However, if there is some other way you think they add subjectivity, please show that. or atleast explain why, using examples with the theory, Using Popper's idea of falsification if you want rather then just using examples of Popper's idea. Sorry if I sound a bit harsh here but, this thread hasnt gone anywhere yet and I would kind of like to see it go somewhere.
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They call 'em fingers, but i've never seen em fing..... oh there they go!! otto |
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If a test can be concieved, then the theory is testable. If the outcome of a test does not allow unambiguous interpretations, other tests are necessary (e.g., Michelson-Morley experiment is not enough to support Special Relativity against a theory based on a material Aether). And, what Popper said did not change the practice of science. Quote:
A double-slit expriment cannot support a purely classical theory of electron.
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papageno "Why waste time learning, when ignorance is instantaneous?" - Hobbes (Calvin and Hobbes) "It's all about context!" - Vince Noir (The Mighty Boosh) "I've never heard of such a brutal and shocking injustice that I cared so little about!" - Zapp Brannigan (Futurama) "...because the logic of the lines traced from reality is as poor of aesthetic value as it is strict in consistency. " - Paolo Bozzi (Naive Physics - free translation) |
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Check it: http://www.eeng.dcu.ie/~tkpw/ If you disapprove of Popper's ideas, then fine, but we are talking about the theory which he formulated, and not one designed to keep russ-watters happy. Quote:
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The point is that they are NOT testable theories in their own right and, more problematically, they fail to meet the strict criteria for qualification as AHs. If they fail to add to the testability of a theory, then by definition they undermine it. Call this subjectivity if you will. Quote:
For a theory to be falsifiable, there must be at least one conceivable test that is capable of falsifiying the theory. For DM to qualify as an AH it must add to the testability of the theory, by adding add least one more test that is vulnerable to being falsified. 1 + 1 = 2 Where this criterium is fulfilled, the theory is improved, that is more testable. (There are now at least 2 tests that can be performed to falsify the theory. See the math above.) If the theory has a leak that is patched by a hypothesis which is not testable, then the theory is undermined. Testable and falsifiable are synonyms in this context, remember. |
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![]() The purpose of this thread is for you to defend your comment, which is included in the thread title. You have focussed on Dark Matter and Dark Energy. Quote:
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I have some reservations about the terms falsifiable and testable being used as synonyms, as I have mentioned, but for the sake of simplicity I happy to overlook them. Where the context is clear my reservations are eased considerably. But let's stick to the point. |
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These predictions can be tested. Many predictions have been tested experimentally and the results agree with the predictions. Quote:
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papageno "Why waste time learning, when ignorance is instantaneous?" - Hobbes (Calvin and Hobbes) "It's all about context!" - Vince Noir (The Mighty Boosh) "I've never heard of such a brutal and shocking injustice that I cared so little about!" - Zapp Brannigan (Futurama) "...because the logic of the lines traced from reality is as poor of aesthetic value as it is strict in consistency. " - Paolo Bozzi (Naive Physics - free translation) |
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The point is, do DM and DE qualify as Falsifiable within his methodology? If you don't approve of his work, then fine, but for the purpose of this thread we cannot ignore it. |
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If you want to know if Dark Matter and Dark Energy are (part of) scientific theories, you should ask scientists. Quote:
And, I think, the BA answered "yes". Quote:
I and others have pointed out that Popper's "methodology" is largely irrelevant for the practice of scientists. Scientists did their job with no problems, well before Popper.
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papageno "Why waste time learning, when ignorance is instantaneous?" - Hobbes (Calvin and Hobbes) "It's all about context!" - Vince Noir (The Mighty Boosh) "I've never heard of such a brutal and shocking injustice that I cared so little about!" - Zapp Brannigan (Futurama) "...because the logic of the lines traced from reality is as poor of aesthetic value as it is strict in consistency. " - Paolo Bozzi (Naive Physics - free translation) |
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