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Dave W.
Info Junkie
USA
26022 Posts |
Posted - 12/14/2011 : 18:47:18 [Permalink]
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Originally posted by Sebastian
Well, obviously many people did, just as some posters in this thread seem to have missed my entire point about the meaning of those markers. | Ridiculing you doesn't mean we've missed your point.The markers are not there to predict the precise year of the next tsunami. Not even the best science can do that. | Duh.The markers have been erected to warn future generations that previous tsunamis have reached certain levels and that it would be unwise to build any substantial dwelling below the level of such markers because of the likelihood of another tsunami, at some indeterminate time in the future, reaching similar levels. | No, that's an inference, and thus a "mere hypothesis" and so - according to your logic, Sebastian - the markers can be safely ignored until "evidence" appears (I suppose in the form of a big honking wave).Surely one doesn't have to understand the science of plate tectonics to appreciate the fact that earthquakes have a habit of recurring, eventually, in areas where they have previously occurred. But one does need to be aware of history. | Your argument depends upon inferring future events from past history.One can speculate about the reasons why such lessons of history are ignored. | One need not speculate at all when you're here insisting that instinct and intuition are justifiable reasons to ignore solid inferences based upon empirical data.It seems that in the interests of economic development many of us learn to become blind to 'inconvenient truths'. We become too trusting of authority instead of just using our noggin or common sense and accepting the possibility that 'experts' and specialists in any particular field can get things wrong. | You're obviously speaking only for yourself.One doesn't need to be a scientist to appreciate the fact that any part of a country that has experienced numerous floods in the past, is likely to experience further floods in the future. | No, but one needs to make an inference from empirical data to come to that conclusion. You refuse to even acknowledge that the data exists with regard to Dark Matter, so if you'd moved to Aneyoshi centuries ago when the village was talking about erecting a marker, you, Sebastian, would have been saying, "well, you don't have any tsunami water samples, the whole idea just seems so over-the-top to me, and my gut feeling is more valid than any of your inferences. So count me out, I'll go build my home down by the beach." |
- Dave W. (Private Msg, EMail) Evidently, I rock! Why not question something for a change? Visit Dave's Psoriasis Info, too. |
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Sebastian
New Member
44 Posts |
Posted - 12/17/2011 : 02:39:47 [Permalink]
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This is in response to Dave W.
Therefore, there is no such thing as "atomic theory," there is only "atomic hypothesis," right? |
Absolutely incorrect! Atomic theory is precisely as correct as all the products based upon such theory. In other words, our current life-style with all the marvelous products of science is a testament to the accuracy of our theories.
That does not mean, of course, that our theories are the absolute truth, just that they are sufficiently accurate and useful to enable us to produce wonderful products, whether such products be amazing antibiotics to cure our diseases, or rockets to reach the moon.
So you are asserting that not only is there no evidence, there isn't a single human being alive today who is capable of discerning anything that might be evidence in favor of Dark Matter. That is, after all, what the idiom "out of his depth" means. And that makes it an extremely strong claim. Do you have any evidence with which to support it? |
Rubbish! I'm not talking only about discerning and observing. Ptolemy was excellent at that. I'm talking about confirming and verifying.
Just as Ptolemy was out of his depth with regard to the heliocentric system, which we now know to be true, the proponents of the Dark Matter and Energy hypothesis may also be out of their depth.
We won't know until the dark stuff is found, if it is ever found.
No, you stated quite clearly that Dark Matter is mythical. What you've said above is not what "mythical" means. |
You're nitpicking, Dave. I'm obviously using the word mythical in the sense of extremely hypothetical. Myths tend to be based upon some factual event that occurred in history, that has probably been exaggerated and distorted through word of mouth transmission. They are not reliable because of the tendency of humans to elaborate and tell stories.
Hypotheses without the possibility of verification are in a similar category. One can let one's imagination run riot, without the check of 'real' verification and falsification.
No, since your intuition and instinct about terms like "evidence" and "inference" and "mythical" is flat-out wrong. Do you think you're entitled to your own dictionary? |
Crikey! Of course I'm entitled to my own dictionary. Every word in a dictionary has a slightly different meaning for every individual. Every Oxford or Webster's English dictionary is identical, in terms of the words on the page, but different in terms of the understanding of each individual reading of those words. Didn't you know that, Dave?
All human beings are uniquely different, with identical twins being less so.
One advantage and a great strength of the scientific method is that terms are more precisely defined than the ordinary, every-day language, so there is less room for poetic license.
My use of the term 'mythical' was clearly provocative in order to stimulate debate. |
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Dave W.
Info Junkie
USA
26022 Posts |
Posted - 12/17/2011 : 07:59:11 [Permalink]
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Originally posted by Sebastian
One advantage and a great strength of the scientific method is that terms are more precisely defined than the ordinary, every-day language, so there is less room for poetic license. | Then I can say that you're using several terms without regard for their scientific meaning, while attempting to criticize a scientific theory. By asserting, as you did, that "Indirect evidence is unconfirmed evidence, hearsay, conjecture, inference, deduction," you've ensured that we all know that you don't have a clue as to what these words mean, scientifically. Either you want to discuss the science of Dark Matter, or you want to be provocative and poetic. Which is it?Absolutely incorrect! Atomic theory is precisely as correct as all the products based upon such theory. | So you're going to move the goalposts again. You once said, "Any theory is only as correct, no more and no less, than the success of the products, applications, effects and consequences based upon the theory." The difference between then and now is a ridiculously obvious attempt to redefine scientific success as being solely based on practical, Earth-bound utility.In other words, our current life-style with all the marvelous products of science is a testament to the accuracy of our theories. | Show me where, in the history of "the scientific method," that "we can build a working machine with this theory" has been used as a sole basis for determining the correctness of the theory.That does not mean, of course, that our theories are the absolute truth, just that they are sufficiently accurate and useful to enable us to produce wonderful products, whether such products be amazing antibiotics to cure our diseases, or rockets to reach the moon. | Such products are not the arbiters of scientific correctness.Rubbish! I'm not talking only about discerning and observing. Ptolemy was excellent at that. I'm talking about confirming and verifying. | That doesn't contradict my assessment of your statement at all.Just as Ptolemy was out of his depth with regard to the heliocentric system, which we now know to be true, the proponents of the Dark Matter and Energy hypothesis may also be out of their depth. | "May?" You're back-pedaling from your previous statement.We won't know until the dark stuff is found, if it is ever found. | It's been found. We just can't go out and grab it.You're nitpicking, Dave. I'm obviously using the word mythical in the sense of extremely hypothetical. | Okay, so you're using your own personal definition again, then.Myths tend to be based upon some factual event that occurred in history, that has probably been exaggerated and distorted through word of mouth transmission. They are not reliable because of the tendency of humans to elaborate and tell stories. | No, they're not reliable because most of the time, they're just made-up.Hypotheses without the possibility of verification are in a similar category. | So you think that it is impossible to verify Dark Matter theory. Please tell us why.One can let one's imagination run riot, without the check of 'real' verification and falsification. | Again, quotes do not supply emphasis, they denote the opposite when used as you have.Crikey! Of course I'm entitled to my own dictionary. | Then you can't be upset when people ridicule you for using words in ways that have never appeared in any dictionary.Every word in a dictionary has a slightly different meaning for every individual. | You're not using words slightly differently, you've been giving them entirely new meanings that they've never had before! You've asserted, for example, that "inference," "deduction" and "conjecture" are all synonyms!Every Oxford or Webster's English dictionary is identical, in terms of the words on the page, but different in terms of the understanding of each individual reading of those words. Didn't you know that, Dave? | You'll have to define the words here as you understand them before I can answer that question.My use of the term 'mythical' was clearly provocative in order to stimulate debate. | No, you can't go back now, after ignoring attempts to discuss your use of the word for so long, and suddenly claim you were just trying to stimulate debate. You've had that for months already. If you wanted a scientific, skeptical discussion then you did not need to engage in any provocation.
I think you've got nothing but that (nothing beyond being a provocateur), because you still refuse to engage with the evidence.
But I just realized something: with regard to Dark Matter, it's not that you refuse to count the horse's teeth, the problem is that you refuse to acknowledge that the horse even exists. |
- Dave W. (Private Msg, EMail) Evidently, I rock! Why not question something for a change? Visit Dave's Psoriasis Info, too. |
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Tim Thompson
New Member
USA
36 Posts |
Posted - 12/17/2011 : 18:36:00 [Permalink]
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On Helio- and Geo-centric systems
Originally posted by Sebastian I'm criticising you for your biased and misleading presentation, not your lack of knowledge of historical events. { ... } Could it be, Tim, that you failed to mention this significant aspect of Tycho's system because it might give the lie to your assertion that the heliocentric system was actually established before the invention of the telescope.
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"Give the lie", you say? I certainly am not lying, to which accusation I protest. I do not believe either that I have presented a biased or misleading story.
Originally posted by Sebastian For example, you talk about Copernicus 'establishing' the heliocentric system without the aid of a telescope whereas it seems clear to me from my readings that Copernicus, more correctly, resurrected a previous hypothesis that had existed for centuries, and gave it new impetus with observation and calculations borrowed from Ptolemy, who was a Geocentrist.
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Reference what I actually said
Originally posted by Tim Thompson
Originally posted by Sebastian The observation that the earth revolves around the sun has been possible only as a result of the laboratory-produced lens in the form of a telescope, which was a scientific endeavour.
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That is a factually incorrect statement. Copernicus clearly began his studies of the heliocentric system as early as 1514, the date on the earliest copy we have of his Commentariolus. He used a combination of his own observations, and those of other astronomers to establish the empirical superiority of the heliocentric system. His major work, De revolutionibus orbium coelestium (On the Revolutions of the Heavenly Spheres) appeared in 1543, shortly before he died. But it is clear that he had actually finished the book sometime before that and deliberately delayed publication until his own death, perhaps to avoid religious persecution. This book has its strength & weaknesses. It is a mathematically complicated book with a considerable amount of what we would now call spherical trigonometry, used to analyze the motions of the planets (I have a copy in my library, On the Revolutions of the Heavenly Spheres, Nicolaus Copernicus, Running Press 2002, edited with commentary by Stephen Hawking). The major strength of this book is that it is not simply philosophical musing over where the sun & earth belong, but a formal, mathematical analysis of the motions of the planets, establishing the empirical superiority of a heliocentric solar system. But its major weakness is that Copernicus could not part with the idea of perfectly circular orbits because they are geometrically "perfect" (later, Galileo suffered the same weakness, and fell out with Kepler over elliptical orbits). This adherence to circles, with the planets attached to heavenly spheres, meant that Copernicus had to retain a system of epicycles to conform with retrograde motions, but his system was still far simpler than the Ptolemaic system.
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I did not say that Copernicus "established the heliocentric system", as if this was the final conclusion. I said, "The major strength of this book is that it is not simply philosophical musing over where the sun & earth belong, but a formal, mathematical analysis of the motions of the planets, establishing the empirical superiority of a heliocentric solar system." What Copernicus actually did do was establish the superiority of the heliocentric system, as compared to a Ptolemaic geocentric system, as concerns its fidelity to observational data and the well known principle of Occam's Razor, favoring the simpler solution. That's not bias, it's simply a statement of fact.
Furthermore, I disagree with your cavalier attitude towards Copernicus's work as compared to earlier geocentric ideas. Copernicus was the first to do a detailed comparison of the motions of the planets between heliocentric & geocentric systems. And he did not simply borrow observations from Ptolemy; he used his own observations and those of other contemporary astronomers. The work published by Copernicus was a significant advance over anything done earlier.
Now, it is well known that there were heliocentric proposals from the ancient Greeks. Aristarchus may be bet known. He did no observations of the motion of the planets; he assumed that Earth moved around the Sun because he recognized the the sun was rather bigger than Earth, although he seriously underestimated both its distance and size. He simply assumed that Earth is the more likely mover because it is smaller, and assumed that extreme distance to the stars explained the absence of parallax. His idea was dominated by assumptions and barely any observation. Copernicus, relied far more on observation and orbits (which were unknown to the Greeks). He didn't simply "resurrect" an old idea (not that the resurrection of old ideas is all that unusual in science), he resurrected an old idea and made major changes to it.
The real pre-telescopic establishment of the heliocentric system comes with Kepler and his analysis of Tycho's data ...
Originally posted by Tim Thompson It was Johannes Kepler who finally nailed down the final basic version of the heliocentric solar system that we use today. Kepler began to work with Tycho Brahe at the Uraniborg Observatory in 1600, and after Tycho died unexpectedly in 1601, Kepler took over his title as "Imperial Mathematician", assigned to complete Tycho's work on the motion of the planets. Kepler had already published his Mysterium Cosmographicum (The Cosmographic Mystery) in 1596, in support of Copernicus but continuing with circular orbits. Kepler finished Astronomia Nova in 1605, but publication was delayed until 1609 by legal disputes with Tycho's family over the use of Tycho's data. In this work Kepler published the first 2 of what we now call Kepler's Laws of Planetary Motion, establishing elliptical orbits instead of circles, and establishing the variable speed of the planets. These two laws of motion were the key to conservation of angular momentum later discovered by Isaac Newton, and Kepler anticipates Newton's law of gravity in his own description of mutual attractions between bodies as the force that keeps the solar system stable (I am quite sure I have a copy of Kepler's books in my library as well but just can't find them at the moment).
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In fact it was Kepler who "established" the heliocentric system, without the aid of a telescope. Even Galileo's observations of the phases of Venus, while they rule out a strictly geocentric system, make room for the hybrid helio-geo-centric system of Tycho Brahe (he has all of the planets orbiting the sun, and then puts that solar system, and the moon, in orbit around Earth. This way he remains consistent with the phases of Venus and the retrograde motions of the planets). However, the notion that this "puts the lie" to what I had said is at best simplistically naive. One need only compare Tycho to Kepler and apply Occam's razor to see the obvious. Kepler's elliptical orbits combined with systematically variable speeds of motion for the planets, in a heliocentric system, are an even better fit to the planetary retrograde motions and the phases of Venus. But even if it were not a better fit, it would be a better model anyway because of its extreme simplicity by comparison (unless the difference between the "better" and "not better" fits is itself extreme, of course).
If you want to be overly pedantic, you could argue that he heliocentric system was really "established" only after the era of spacecraft navigation through the solar system. But very few, if any, would accept that the heliocentric system was not well established as a fact before that.
On Dark Matter
Originally posted by Sebastian
Originally posted by Tim Thompson
My points, directly stated are these: (1) The hypothesis of dark matter is superior to all known alternative hypotheses, by virtue of superior consistency with observational data.
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Galileo's assertion that the earth revolved around the sun lacked a solid or persuasive rationale in terms of the Mathematics and Physics of the times, and was seen by the church to be an unjustified and provocative stance. Is this not true?
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No, that is not true. Both Copernicus and Kepler provided significant rationale in terms or mathematics, which was well developed by then, and what passed for physics at those times, specifically what we would now call orbital mechanics (in this regard Kepler was to Newton as Faraday was to Maxwell; Kepler and Faraday laid the practical groundwork that Newton & Maxwell turned into expansive theories of physics). The only observational sticking point was the evident absence of parallax, but Aristarchus had already dealt with that thousands of years previously with the obvious conjecture that the stars were too far away, a notion that Galileo's contemporaries did not wish to honor.
Originally posted by Sebastian There is no reliable and concrete evidence for the existence of dark matter. There is only inference. Inference is not evidence. It's hypothesis.
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I reject that claim, and furthermore I assert that the discipline of science systematically rejects the idea as well. Not only is inference definitely evidence, but in fact the vast majority of what passes for evidence in all branches of science is inference. Only a small portion of what we call "evidence" is not inference. The difference between "weak" and "strong" evidence is really the level of confidence one has that the inference is correct.
Originally posted by Sebastian I accept that the proposed existence of Dark Matter is a hypothesis. It might turn out to be true eventually, but at the moment its existence is a mere hypothesis. I'm entitled to have my doubts based upon intuition and instinct, am I not.
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Hypothesis indeed it is, nobody I know of argues otherwise, although I disagree with the qualification "mere", as if hypotheses are all created equally "mere". That is surely far from the truth. And while you are entitled to all the doubts you like, you are not entitled to expect anyone else to agree with you.
Originally posted by Sebastian Just as Ptolemy was out of his depth with regard to the heliocentric system, which we now know to be true, the proponents of the Dark Matter and Energy hypothesis may also be out of their depth. We won't know until the dark stuff is found, if it is ever found.
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I disagree as well here. We can and will know, even if neither dark matter or dark energy are never "directly" observed. You seriously underestimate the power & authority of inference from observation as the life-breath of science; see the following ...
Originally posted by Sebastian I'm talking about confirming and verifying. { ... } Hypotheses without the possibility of verification are in a similar category. One can let one's imagination run riot, without the check of 'real' verification and falsification.
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I agree with the notion that, "Hypotheses without the possibility of verification are in a similar category", but it remains evident that you & I disagree on what qualifies as an "real" verification or falsifications, which brings us right back to the doorstep of inference from observation.
Originally posted by Tim Thompson
The following quote comes from a message I posted on 1 February, 2010, on the JREF Forum: What is Empirical Science? III
Originally posted elsewhere by Tim Thompson (1 Feb 2010)
Question 2 The standard definition of the word "empirical" does not require a controlled experiment, or for that matter, any kind of experiment at all. Why do you feel justified in changing the definition of a word (any word, but in particular this one), and then complaining when the rest of the world does not use it your way? For standard usage of the word "empirical", see for instance the definition from the online Merriam-Webster dictionary.
Case in point I quote from the book An Introduction to Scientific Research by E. Bright Wilson, Jr.; McGraw-Hill, 1952 (Dover reprint, 1990); page 27-28, section 3.7 "The Testing of Hypotheses"; emphasis from the original. [indent] "In many cases hypotheses are so simple and their consequences so obvious that it becomes possible to test them directly. New observations on selected aspects of nature may be made, or more often an experiment can be performed for the test. There is no clear cut distinction between an experiment and a simple observation, but ordinarily in an experiment the observer interferes to some extent with nature and creates conditions or events favorable to his purpose." [/indent] Wilson says "There is no clear cut distinction between an experiment and a simple observation," and that is the way the entire scientific community currently operates. Are you now telling us that the entire scientific community is using a flawed concept of empiricism?
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First, I recommend readers see the entire message, as it is a significant discussion of the evidence favoring the dark matter hypothesis (also see this message).
So what is a "real" verification? I say that astronomical observations count as "real" and "real" verification can arrive thereby. Evidently, there is a significant community of practicing astronomers & astrophysicists & cosmologists & etc. who agree. And evidently, so does E. Bright Wilson. The idea that verification does not become "real" until a controlled laboratory experiment is performed is unacceptable to me, and it appears that it is equally unacceptable to a lot of other scientist. Controlled laboratory experiments and uncontrolled observations of raw nature are equally valuable in practice & in principle, and equally capable of providing "real" verification or falsification.
And finally, I do not accept the implication that dark matter is inferred from observation by scientists who "let one's imagination run riot". In fact that idea has grown out of decades of careful consideration, and the slow realization that every known explanation fails, forcing one to consider the "unknown" explanations. That's not rampant imagination, that's science.
Note that while I am on holiday travels, I might not be as swift as usual in responding |
The point of philosophy is to start with something so simple as not to seem worth stating, and to end with something so paradoxical that no one will believe it. -- Bertrand Russell |
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Sebastian
New Member
44 Posts |
Posted - 12/19/2011 : 20:50:59 [Permalink]
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"Give the lie", you say? I certainly am not lying, to which accusation I protest. I do not believe either that I have presented a biased or misleading story. |
Tim, there is a subtle distinction between the expression that a particular statement 'gives the lie', and an accusation that the person making the statement is a liar.
I'm not calling you a liar. I'm simply saying you are unwittingly biased.
Being biased is a normal attribute of the human condition. There are about 6.5 billion people on the planet, and only one person is free from bias, and that's me . (That's a joke, by the way).
Scientists in general are far more biased than the public imagine. The incessant testing of scientific procedures necessary for the production of beneficial products that actually work in a marvelous and unambiguous way, tends to create the impression amongst the scientifically illiterate public that a concensus of scientific opinon on any subject settles the matter.
We know from history this is far from the truth. However, History is another discipline subject to extreme bias. Whether it's the history relating to Jesus Christ, or the history relating to the scientific endeavours in the Middle Ages, bias is present, and sometimes extreme.
It is said that history is written by the victors. Why should that not apply to the history of science?
I get a strong sense, Tim, that with the benfit of hindsight you are going back in time and reinterpreting history.
These names, Copernicus, Tycho Brahe, Kepler and Galileo, keep cropping up on any search on the internet as though they were the only intelligent and thoughtful people of the era who had any opinions on the Heliocentric versus Geocentric hypothesis.
I find this incredible. These great scientists did not work in a vacuum.
Because we now know for certain, as a result of our modeling, verification, falsification procedures, and fantastic telescopes, that all the planets revolve around the sun and that the stars are billions of miles away, it becomes very easy for someone like you to go back in time, project your modern understanding of the issues on those distant events, and claim that those earlier, tentative hypotheses were established fact.
The reality in my view is vastly different. It's understood that any proponent of a hypothesis tends to believe in it. Fred Hoyle believed in his 'steady state' theory, in opposition to the Big Bang, until the end of his life.
In the absence of scientific verification one can do that. Fred Hoyle was not an idiot, by any means.
A concensus of opinion on any scientific matter does not necessarily settle the matter if the nature of the subject is beyond verification, as is Dark Matter, and as is Anthropogenic Climate Change.
The following extract from Dr Roy Spencer's site expresses the problem quite succinctly.
Even if we have perfect measurements of Nature, scientists can still come to different conclusions about what those measurements mean in terms of cause and effect. So, biases on the part of scientists inevitably influence their opinions. The formation of a hypothesis of how nature works is always biased by the scientist’s worldview and limited amount of knowledge, as well as the limited availability of research funding from a government that has biased policy interests to preserve. |
Another quote from Tim.
What Copernicus actually did do was establish the superiority of the heliocentric system, as compared to a Ptolemaic geocentric system, as concerns its fidelity to observational data and the well known principle of Occam's Razor, favoring the simpler solution. That's not bias, it's simply a statement of fact. |
No. You're absolutely wrong, Tim. The superiority of the heliocentric system, as proposed by Copernicus, has been established by you, and other later scientists who had the benefit of telescopes and modern technology.
During the times of Copernicus, there was great doubt about the entire issue, amongst other, highly intelligent thinkers whom we simple don't hear about.
The scientist/historian Pierre Duhem got into serious trouble proposing that the Middle Ages were not as dark as some people imagine. There were also some highly significant ideas spreading from certain Moslems in the Middle Ages, specifically those of Ibn al-Haytham, who is considered by many to be the first true scientist who refuted the ideas of Aristotle.
If your livelihood, reputation, income and promotion prospects are tied to your scientific work, it's almost inevitable that you will be biased.
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Dr. Mabuse
Septic Fiend
Sweden
9688 Posts |
Posted - 12/19/2011 : 23:56:20 [Permalink]
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Originally posted by Sebastian
(That's a joke, by the way).
| In the context of this discussion, it's not even remotely funny, in my not so humble opinion. |
Dr. Mabuse - "When the going gets tough, the tough get Duct-tape..." Dr. Mabuse whisper.mp3
"Equivocation is not just a job, for a creationist it's a way of life..." Dr. Mabuse
Support American Troops in Iraq: Send them unarmed civilians for target practice.. Collateralmurder. |
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Dave W.
Info Junkie
USA
26022 Posts |
Posted - 12/20/2011 : 08:52:52 [Permalink]
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Originally posted by Sebastian
A concensus of opinion on any scientific matter does not necessarily settle the matter... | You can lay off attacking this strawman....if the nature of the subject is beyond verification, as is Dark Matter, and as is Anthropogenic Climate Change. | Well, that contradicts your earlier position. Now you're claiming that Dark Matter and AGW aren't even scientific fields, because they cannot be verified. So you're back to claiming that Dark Matter is mythical, in the proper dictionary sense.The following extract from Dr Roy Spencer's site expresses the problem quite succinctly. | Wow, that guy is a joke: "In the case of global warming research, the alternative (non-consensus) hypothesis that some or most of the climate change we have observed is natural..." No, the null hypothesis is that little or none of the warming is anthropogenic. The consensus hypothesis is that most (not all) of the warming is due to human activity. That's most as in "more than 50%." For Spencer to be correct, the consensus hypothesis would have to be that 100% of the warming we see is anthropogenic, but the consensus isn't so stupid as that, scientists already know that some of the warming is natural. For Spencer to make such a blatantly biased attack in a piece about eliminating bias is a sure sign that he's not a good source of info.If your livelihood, reputation, income and promotion prospects are tied to your scientific work, it's almost inevitable that you will be biased. | Then you should have data showing the bias, instead of just making these insinuations. But you refuse to address any data about anything. |
- Dave W. (Private Msg, EMail) Evidently, I rock! Why not question something for a change? Visit Dave's Psoriasis Info, too. |
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Sebastian
New Member
44 Posts |
Posted - 12/21/2011 : 22:03:38 [Permalink]
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Dave W writes:
Then you should have data showing the bias, instead of just making these insinuations. But you refuse to address any data about anything. |
The data showing the bias would fill more than an entire encyclopedia. Bias is the human condition, Dave. To be biased is to be human. We're all biased, except me. I arrived in a time capsule from outer space (Joke!).
For the benifit of those who may be skeptical about the existence of scientific bias, I provide the following links, at random, from a Google search. Some of these articles may be written by people who are biased.
http://en.wikipedia.org/wiki/Selection_bias http://landshape.org/enm/example-of-scientific-bias/ http://www.abortionbreastcancer.com/examples_of_bias_in_the_scientific_community/ http://www.scienceagogo.com/news/20020011205947data_trunc_sys.shtml http://www.experiment-resources.com/research-bias.html http://teacher.pas.rochester.edu/phy_labs/appendixe/appendixe.html http://blog.lib.umn.edu/denis036/thisweekinevolution/2008/08/bias_in_science_vs_honest_erro.html http://arstechnica.com/science/news/2010/07/confirmation-bias-how-to-avoid-it.ars http://theinconvenientskeptic.com/2011/01/understanding-scientific-bias-part-2/ http://www.transforming-child-behavior.com/scientificbias.html http://www.bmartin.cc/pubs/79bias/pp4-7.html http://www.wisegeek.com/what-is-a-confirmation-bias.htm http://socrates.berkeley.edu/~maccoun/ar_bias.html http://blogs.discovermagazine.com/80beats/2011/06/15/study-stephen-jay-gould-crusader-against-scientific-bias-was-guilty-of-it/ http://classic.the-scientist.com/blog/display/54893/ http://www.plosmedicine.org/article/info:doi/10.1371/journal.pmed.0020124
Well, that contradicts your earlier position. Now you're claiming that Dark Matter and AGW aren't even scientific fields, because they cannot be verified. So you're back to claiming that Dark Matter is mythical, in the proper dictionary sense. |
Where did I write that Dark Matter and AGW aren't scientific fields? How could you possibly arrive at such an interpretation from anything I've written in this thread?
That these matters, Dark Energy and Anthropogenic Climate Change are currently beyond scientific verification and falsification must be obvious to all thinking people. How could you not be aware of that?
If the complexities of climate and all the factors that influence it were fully understood, there would be no problem. We'd deal with any verified and certain threat to our well-being as a result of our CO2 emissions, because we would know that we would have no option, just as we'd deal with the threat of an asteroid hurtling towards earth, once it was established that its trajectory was in line with a direct hit which would cause massive devastation.
The wealthy nations would immediately organise the launch of rockets with nuclear war heads to blast the asteroid out of its current path or destroy it completely.
Wow, that guy is a joke: "In the case of global warming research, the alternative (non-consensus) hypothesis that some or most of the climate change we have observed is natural..." No, the null hypothesis is that little or none of the warming is anthropogenic. The consensus hypothesis is that most (not all) of the warming is due to human activity. That's most as in "more than 50%." For Spencer to be correct, the consensus hypothesis would have to be that 100% of the warming we see is anthropogenic, but the consensus isn't so stupid as that, scientists already know that some of the warming is natural. For Spencer to make such a blatantly biased attack in a piece about eliminating bias is a sure sign that he's not a good source of info. |
It seems strange that NASA would employ him if he's really such a joke. It seems strange that the American education system could have awarded him a PhD in meteorology if he's such a joke. It seems strange that he would be invited to provide testimony to the United States Congress, several times, on climate change matters, if he is such a fruitcake.
Do you have any evidence that the following summary of Dr Roy Spencer's achievements is incorrect?
Roy W. Spencer received his Ph.D. in meteorology at the University of Wisconsin-Madison in 1981. Before becoming a Principal Research Scientist at the University of Alabama in Huntsville in 2001, he was a Senior Scientist for Climate Studies at NASA’s Marshall Space Flight Center, where he and Dr. John Christy received NASA’s Exceptional Scientific Achievement Medal for their global temperature monitoring work with satellites. Dr. Spencer’s work with NASA continues as the U.S. Science Team leader for the Advanced Microwave Scanning Radiometer flying on NASA’s Aqua satellite. He has provided congressional testimony several times on the subject of global warming. |
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Dave W.
Info Junkie
USA
26022 Posts |
Posted - 12/22/2011 : 07:31:17 [Permalink]
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Are you really this idiotic, or are you just pretending? The fact that scientific bias exists doesn't mean that it's responsible for any particular scientific conclusion. Without evidence that bias is responsible for current Dark Matter theory, you're just making an insinuation, and not presenting a serious argument.
Imagine if you were arguing that the best ping-pong players are using performance-enhancing drugs, and all you could come up with is the fact that in other sports such drugs are quite common. Would that have any bearing on the ping-pong players? Of course not.Well, that contradicts your earlier position. Now you're claiming that Dark Matter and AGW aren't even scientific fields, because they cannot be verified. So you're back to claiming that Dark Matter is mythical, in the proper dictionary sense. | Where did I write that Dark Matter and AGW aren't scientific fields? How could you possibly arrive at such an interpretation from anything I've written in this thread?
That these matters, Dark Energy and Anthropogenic Climate Change are currently beyond scientific verification and falsification... | Oh, well, if you're going to qualify your statement now with the word "currently," that makes all the difference. Your earlier statement included no such adverb....must be obvious to all thinking people. How could you not be aware of that? | I guess even the scientists who doubt Dark Matter theory aren't "thinking people," then.If the complexities of climate and all the factors that influence it were fully understood, there would be no problem. | Since evolutionary biology isn't "fully understood," then I guess you'll claim that it is "currently beyond verification and falsification," right? Of course not. The idea that a field must be "fully understood" to be verifiable or falsifiable is ludicrous.We'd deal with any verified and certain threat to our well-being as a result of our CO2 emissions, because we would know that we would have no option... | No, you're still confusing a scientific theory with its political consequences....just as we'd deal with the threat of an asteroid hurtling towards earth, once it was established that its trajectory was in line with a direct hit which would cause massive devastation. | No, predicting the path of an asteroid requires an inference, which you've said is a synonym for conjecture.The wealthy nations would immediately organise the launch of rockets with nuclear war heads to blast the asteroid out of its current path or destroy it completely. | That's a political choice, and has nothing to do with the state of the science. Some people would instead choose to burn down the observatories.Wow, that guy is a joke: "In the case of global warming research, the alternative (non-consensus) hypothesis that some or most of the climate change we have observed is natural..." No, the null hypothesis is that little or none of the warming is anthropogenic. The consensus hypothesis is that most (not all) of the warming is due to human activity. That's most as in "more than 50%." For Spencer to be correct, the consensus hypothesis would have to be that 100% of the warming we see is anthropogenic, but the consensus isn't so stupid as that, scientists already know that some of the warming is natural. For Spencer to make such a blatantly biased attack in a piece about eliminating bias is a sure sign that he's not a good source of info. | It seems strange that NASA would employ him if he's really such a joke. It seems strange that the American education system could have awarded him a PhD in meteorology if he's such a joke. It seems strange that he would be invited to provide testimony to the United States Congress, several times, on climate change matters, if he is such a fruitcake.
Do you have any evidence that the following summary of Dr Roy Spencer's achievements is incorrect?Roy W. Spencer received his Ph.D. in meteorology at the University of Wisconsin-Madison in 1981. Before becoming a Principal Research Scientist at the University of Alabama in Huntsville in 2001, he was a Senior Scientist for Climate Studies at NASA’s Marshall Space Flight Center, where he and Dr. John Christy received NASA’s Exceptional Scientific Achievement Medal for their global temperature monitoring work with satellites. Dr. Spencer’s work with NASA continues as the U.S. Science Team leader for the Advanced Microwave Scanning Radiometer flying on NASA’s Aqua satellite. He has provided congressional testimony several times on the subject of global warming. |
| So you couldn't address the precise criticism I provided of Dr. Spencer, so instead you make arguments from incredulity and authority, and try to shift the burden of proof.
That's your pattern, Sebastian. You ignore the substantive logic and evidence in favor of vague innuendo, fallacious arguments and massive hypocrisy. You refuse to count the horse's teeth. You are a joke. |
- Dave W. (Private Msg, EMail) Evidently, I rock! Why not question something for a change? Visit Dave's Psoriasis Info, too. |
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Tim Thompson
New Member
USA
36 Posts |
Posted - 12/22/2011 : 14:05:58 [Permalink]
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Originally posted by Sebastian
That these matters, Dark Energy and Anthropogenic Climate Change are currently beyond scientific verification and falsification must be obvious to all thinking people. How could you not be aware of that?
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On both points you are absolutely wrong; neither is beyond verification, and I assert that there is significant evidence arguing in favor of verification on both accounts. On the matter of AGW, your Dr. Spencer is certainly wrong, and so are you, but I do not wish to discuss this in a thread that is supposed to be about cosmology, where AGW is grossly off-topic. Start a thread on global warming in the appropriate area and I will discuss it there.
As for dark matter, I have already presented copious valid evidence on the topic, which you seem bound & determined to dismiss, without intellectual reflection, as being not evidence at all because it is only "inference from observation". But I submit that you know and understand significantly less than you think you do, as to what constitutes a valid exercise of scientific practice (see, for instance, my post from November 11).
So far you seem primarily to present very vague & general comments about bias in science, but little specific and to the point, which does not impress me. For instance, your list includes "selection bias", and you apparently pretend this is a serious reason to not take astronomy seriously. But you fail to notice that the entire astronomical community is well aware of selection bias, and in most publications take that selection bias explicitly into account (and the few that don't are quickly criticized for that failure).
If your point is simply that "bias exists", is that supposed to be news? Of course it does, so what? But if you can't demonstrate specific bias in the specific arguments presented, then you have in fact nothing interesting to say.
Now, about specifics, ...
Originally posted by Sebastian No. You're absolutely wrong, Tim. The superiority of the heliocentric system, as proposed by Copernicus, has been established by you, and other later scientists who had the benefit of telescopes and modern technology.
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No, you are absolutely wrong. Nobody directly questioned any of Copernicus's specific conclusions. In fact, quite the opposite, his contemporaries quickly accepted his results. The official position of the church was that they had no problem using Copernicus's methods to calculate predictions for the planets; they recognized at once that his system was in fact superior in exactly the manner in which I claimed, but accepted it only as a calculational tool, and not a true statement of physical reality. Tycho, Galileo and Kepler all rejected the physical reality of a geocentric system. Church astronomers rejected heliocentric systems partly for flawed intellectual reasons (e.g., the absence of parallax, flawed by the failure to appreciate the effect of distance that Aristarchus had recognized millenia before) but primarily out of political and philosophical bias ("religious" is really the wrong word, since the bias comes from the Pope not from the Bible). Since it was the time of the Protestant Reformation, there was significant politics at work, so one can hardly argue that all of the "bias" is on the heliocentric side of the argument.
No, the superiority of the heliocentric system was firmly established and routinely accepted throughout the astronomical community, well before the advent of telescopes.
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The point of philosophy is to start with something so simple as not to seem worth stating, and to end with something so paradoxical that no one will believe it. -- Bertrand Russell |
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Sebastian
New Member
44 Posts |
Posted - 01/03/2012 : 00:39:24 [Permalink]
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Well, there's certainly not much happening in this thread over the holidays. I'm wondering if you are all a lost cause. Dave W calls me an idiot, so there's obviously no scope for dialogue there.
Tim Thonpson is more reasonable and simply states I am absolutely wrong on a subject which, by its nature, is a contentious and unsettled issue.
I'm not surprised by such attitudes, just disappointed. The world has always been in a mess from a human perspective, with different power factions fighting it out, either physically in terms of war with the awful destruction of life and property, or in terms of dialectical argument with religion versus evolution, or the benefits of wholemeal bread (and brown rice) versus white bread (and white rice), to bring it to a more mundane level.
When an advanced society like Japan builds a nuclear power plant below numerous marked levels indicating the height of numerous previous tsunamis stretching back 600 years, one can see the enormous power of bias.
Tim Thompson writes:
If your point is simply that "bias exists", is that supposed to be news? Of course it does, so what? But if you can't demonstrate specific bias in the specific arguments presented, then you have in fact nothing interesting to say. |
thus demonstrating that he doesn't understand bias.
Bias is not something that is neutralised, or becomes ineffective, simply because people are aware of the concept. Sigmund Freud and Carl Jung described the powerful effect that the subconscious can have on our actions and motivations.
Does that mean therefore, because we know there is a subconscious that influences our decisions and choices, because it's been reported by Freud and Jung, then it's no longer a problem?
Clearly not. The nature of the subconscious, and the nature of bias, is that it is largely hidden from the individual. He/she may be aware of it as a general principle, but not necessarily aware of it as it applies him/her with so many human concerns about fame, money, reputation, job security etc.
The human capacity for self-delusion is astoundingly great, as is his capacity for conformity.
There's an interesting experiment I heard of recently which was designed to test this tendency to conform.
A group of experts on a particular subject were seated around a table and each given a scenario of two choices on the particular matter, called A and B. Within the specialised subject, it would be very clear that B was the sound, reasonable and preferred option.
However, around this table there was only one true expert who would appreciate that B was the sensible option. All the others were mere actors.
The experiment was arranged so that each member around the table would vote in sequence for either A or B, with the last person to vote being the only true expert at the table. There may have been 10 or 12 people at the table.
The actors were instructed to vote for A. Would the last person to vote, the true expert who understood the issues and knew that B was the sensible option, vote for B against the consensus opinion of those whom he assumed were his peers?
Answer: No! Going against the majority opinion of one's peers takes more guts than probably most scientists have. This one and only expert who knew and appreciated why the B option was better, voted for A.
Need I continue? |
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Dr. Mabuse
Septic Fiend
Sweden
9688 Posts |
Posted - 01/03/2012 : 03:19:50 [Permalink]
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Originally posted by Sebastian Dave W calls me an idiot,
| No. He asked you if you were that idiotic, or if there was another reason for your apparent stance on bias within scientific endeavours. That's not the same thing, though I have to say I'm leaning toward one answer more than the other.
so there's obviously no scope for dialogue there. | If you intentionally misinterpret what is written, then yes you're limiting the dialogue.
I'm not surprised by such attitudes, just disappointed. The world has always been in a mess from a human perspective, with different power factions fighting it out, either physically in terms of war with the awful destruction of life and property, or in terms of dialectical argument with religion versus evolution, or the benefits of wholemeal bread (and brown rice) versus white bread (and white rice), to bring it to a more mundane level. | Now it's time to me to ask what you've been smoking. (so I can stay away from it) In a logical argument between religion and evolution, one wins over the other hands down, because one side lacks several key components for a successful argument. The devil is in the details.
Your campaign of innuendo against the science of Dark Matter, or Anthropogenic Global Warming is transparent and not successful. One the contrary, your criticisms shoot your own argument in the foot.
When an advanced society like Japan builds a nuclear power plant below numerous marked levels indicating the height of numerous previous tsunamis stretching back 600 years, one can see the enormous power of bias. | Building the power-plants there was a political/economical decision, not a scientific one. It's disingenuous of you to lay blame where it does not belong.
Bias is not something that is neutralised, or becomes ineffective, simply because people are aware of the concept. Sigmund Freud and Carl Jung described the powerful effect that the subconscious can have on our actions and motivations. | That's par of the reasons we have peer-review publications, where different people, with different biases, may come together and provide critique and insights to address biases which may transferred from the subconscious to the paper.
The human capacity for self-delusion is astoundingly great, as is his capacity for conformity. | That is true enough. I submit your rejection of Dark Matter and AGW as mythical, as evidence of your self-delusion. A delusion which may or may not be based in your subconsciousness and thus by definition unknowable by you, but for the rest of us to see plainly.
There's an interesting experiment I heard of recently which was designed to test this tendency to conform.
<snip>
| That is the setup of a classic psychological experiment on peer pressure, and how it affects judgement calls. But making taking a stand on a question which requires a judgement call is very different from a question which can be answered with facts and evidence.
So the expert failed in standing against peer-pressure on a subject requiring his judgement call, and not his reliance on facts and evidence.
Going against the majority opinion of one's peers takes more guts than probably most scientists have. | In this particular instance, obviously. But you're making an assumption that all scientists are equally weak-minded and are making an inference from that based in a sample size of one. By your own reasoning, that inference isn't evidence but nearly as bad as conjecture, this example is just as insignificant that your last flatus. It merely stinks but pretty much nothing else came of it. And a sample size of one isn't very significant. I have an example of my own where a friend of mine was subjected to the same experiment. He passed. When my anecdote contradicts yours, which one is right? He's a member of my bike club, I could refer to him if necessary. His name is Eric, and can be reached at this forum. Now, where's the link where I can verify that your scientist experiment isn't just made up?
This one and only expert who knew and appreciated why the B option was better, voted for A.
Need I continue?
| Yes. You haven't managed to make a convincing argument yet.
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Dr. Mabuse - "When the going gets tough, the tough get Duct-tape..." Dr. Mabuse whisper.mp3
"Equivocation is not just a job, for a creationist it's a way of life..." Dr. Mabuse
Support American Troops in Iraq: Send them unarmed civilians for target practice.. Collateralmurder. |
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sailingsoul
SFN Addict
2830 Posts |
Posted - 01/03/2012 : 09:38:14 [Permalink]
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By Sebastian,,, This one and only expert who knew and appreciated why the B option was better, voted for A.
Need I continue?
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By Dr. Mabuse,,, Yes. You haven't managed to make a convincing argument yet.
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That's your call. I thought you realized that you were getting nowhere and gave up. If you do continue and want to achieve anything, try sticking to one topic. Stick to any one of several you brought in like the topic of "the existence of Dark Matter and Energy". Tsunami markers in Japan and Japan's reactor placement have no place in that topic. You brought them into this, they are not related to the topic or are unable support your position on DM & DE if that is the topic. It might not be possible for you to stay on one topic, as is suggested in you opening post.
Hello. This is my first post on this site. I came across the site accidentally whilst doing a Google search on the historical references to Pontius Pilate. I'd heard (hearsay) that Pontius Pilate had at some stage of his career been recalled to Rome to be chastised for his excessively brutal treatment of misbehaving Jews.
I wanted to know if this event took place before or after the crucifixion of Christ. |
OK that is a pretty straight forward opening and you continue on topic until you got to,,,
Why am I making my first post in the astronomy section? It's because I still can't come to grips with the current assessment by astrophysicists that 90% of the matter and energy in the universe is invisible and unknown. |
So apparently these are somehow related? I see no connection. I have no clue why you started with "Pontius Pilate" and "his excessively brutal treatment of misbehaving Jews" like they are connected with astrophysics and the topic of DM & DE. You see a connection apparently. Yes there confusion big time going on. If there is a connection I am confused and would like you to point out the connection. If you can't or don't explain the connection, than you are confused and attempt to ignore your confusion by not addressing my point.
As far as discussing ONE topic an a time I'll start first, with the first topic raised.
I wanted to know if this event took place before or after the crucifixion of Christ. |
I think the whole story of what went on is nothing more than christian folklore. I believe this because it comes from the new testament. Being from the NT it might have been written decades even centuries after the fact. If the information came from court records or government archives from that time I would not consider it folklore. If it was written even 50 years after the fact, that makes it folklore in my mind.
As I understand the folklore it happened after Jesus' death. If it happened before than he would have let Jesus live as to not continue with "excessively brutal treatment of misbehaving Jews". |
There are only two types of religious people, the deceivers and the deceived. SS |
Edited by - sailingsoul on 01/03/2012 09:41:28 |
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Dave W.
Info Junkie
USA
26022 Posts |
Posted - 01/03/2012 : 09:55:51 [Permalink]
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Originally posted by Sebastian
Well, there's certainly not much happening in this thread over the holidays. | I (for one) was waiting for you to actually engage with some of the real data, instead of just insisting that it doesn't exist or offering more cowardly innuendos. And with your latest offering, that wait continues.I'm wondering if you are all a lost cause. | Look in the mirror.Dave W calls me an idiot, so there's obviously no scope for dialogue there. | You called me worse when you suggested that no "thinking person" would disagree with you. By your standards, you are incapable of dialogue for having insulted me. Whiny hypocrite.Tim Thonpson is more reasonable and simply states I am absolutely wrong on a subject which, by its nature, is a contentious and unsettled issue. | What constitutes scientific evidence is not contentious or unsettled. You denying, for example, that "indirect evidence" is the primary means of hypothesis testing doesn't make any subject controversial, it just makes you look the fool.I'm not surprised by such attitudes, just disappointed. | Your concern trolling is noted and rejected as appalling condescension.Bias is not something that is neutralised, or becomes ineffective, simply because people are aware of the concept. | No, but claims of bias are neutralized when the claimant refuses to support his claims with evidence. You know, like showing a Dark Matter or AGW paper where the data is clearly opposed to the written conclusion. That would demonstrate bias. Saying that bias exists among scientists doesn't demonstrate that bias is responsible for any particular scientific conclusion.The nature of the subconscious, and the nature of bias, is that it is largely hidden from the individual. He/she may be aware of it as a general principle, but not necessarily aware of it as it applies him/her with so many human concerns about fame, money, reputation, job security etc. | You are a shining, irony-filled example of that, Sebastian.Going against the majority opinion of one's peers takes more guts than probably most scientists have... | So now you are claiming that scientists who agree with Dark Matter theory or AGW are cowards who act out of peer pressure alone.Continue to dig yourself deeper into your hole? Of course not. You can stop and address the evidence any time you like. You have the power, there. It's your decision to make. I (at least) won't hold any of your previous statements against you if you were to start making sensible arguments about real data, so you can choose to wipe the slate clean and start over again. Or not. It's all up to you.
Continue on as you have been if you must, but you won't save face by doing so. |
- Dave W. (Private Msg, EMail) Evidently, I rock! Why not question something for a change? Visit Dave's Psoriasis Info, too. |
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Tim Thompson
New Member
USA
36 Posts |
Posted - 01/11/2012 : 01:01:53 [Permalink]
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I said ...
Originally posted by Tim Thompson
Originally posted by Sebastian
That these matters, Dark Energy and Anthropogenic Climate Change are currently beyond scientific verification and falsification must be obvious to all thinking people. How could you not be aware of that?
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On both points you are absolutely wrong; neither is beyond verification, and I assert that there is significant evidence arguing in favor of verification on both accounts. On the matter of AGW, your Dr. Spencer is certainly wrong, and so are you, but I do not wish to discuss this in a thread that is supposed to be about cosmology, where AGW is grossly off-topic. Start a thread on global warming in the appropriate area and I will discuss it there.
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To which the usually incomprehensible Sebastian replied ...
Originally posted by Sebastian Tim Thompson is more reasonable and simply states I am absolutely wrong on a subject which, by its nature, is a contentious and unsettled issue. I'm not surprised by such attitudes, just disappointed.
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I think Sebastian's "disappointment" is nothing more than a symptom of his ignorance. There is a significant difference between "beyond scientific verification and falsification", as he claimed before, and simply "contentious and unsettled", and anyone who understands rudimentary English, either as a native speaker or as a second language, should surely understand that without me having to point it out.
As I said before, I will not discuss global warming in this thread as it is off-topic. However, dark matter & dark energy as topics in cosmological science are definitely relevant.
So what exactly do "scientific verification" and "scientific falsification" actually mean? Verification is the act of demonstrating logical consistency between observations accepted as unflawed and a proposed hypothesis or theory, so that the hypothesis must be true. Likewise, falsification is the demonstration that a given hypothesis or theory is inconsistent with observation and therefore must be considered false. Of course, in reality, "must be" is replaced by the more pragmatic "is likely to be". The larger the weight of evidence for consistency, the stronger the conviction amongst scientists that the hypothesis is valid, and likewise for falsification. It is rare that any hypothesis or theory has a truly unanimous track record, never failing a single observational test. Those that do, such as the hypothesis of conservation of energy & momentum, or the 2nd law of thermodynamics, are elevated to the supreme status of "laws" and the community of scientists will not consider any claim that they stand violated, absent extraordinarily convincing evidence.
Is it possible to scientifically verify the existence of dark matter? Of course it is, and the claim that the hypothesis is "beyond scientific verification and falsification", which Sebastian tells us, "must be obvious to all thinking people", is not only not obvious, it is absurd in the extreme. There is certainly no reason to believe that the particles that make up dark matter, if it exists, are undetectable by any technology that we possess. Quite the opposite, there are very good reasons to assume that those particles should be detectable, and there are numerous experiments currently in operation looking for them. While there is no unambiguous evidence of a positive direct detection, there is ambiguous evidence that there have been positive direct detections, and further extended research is required to remove the ambiguity. I have documented those experiments elsewhere in detail and refer the reader there rather than resorting to extensive exercises of cut & paste; see post 198353 (11 Nov 2011) and post 198863 (08 Dec 2011). I am expressly intolerant of the notion that it cannot be possible to directly verify, or falsify, the presence of particulate dark matter, when the notion itself is so easily falsified.
There is another hypothesis that competes for scientific attention with dark matter: The "modified gravity" hypothesis. Generally speaking, it is the obvious realization that by modifying general relativity (that is, the theory of gravity), one can produce exactly the same observed effects as are attributed to dark matter. So, which is it? There are several ways to modify gravity, all with their own champions, but so far none of them have been able to produce consistency with so wide a collection of observation as the more mundane notion of dark matter. Hence, and for obvious reasons, the relevant community of scientists favor the dark matter hypothesis. This certainly does not mean that all scientists everywhere now consider the argument settled in favor of dark matter (I get the distinct impression from Sebastian's writing that he thinks that scientists do think exactly that, in which case he is wrong there too).
To the documentary evidence I have already provided, which clearly falsifies the notion that the dark matter hypothesis is in any way "beyond scientific verification and falsification", add the following recent sources ...
Possibility of a Dark Matter Interpretation for the Excess in Isotropic Radio Emission Reported by ARCADE by Nicolao Fornengo, et al., Physical Review Letters 107, 271302, 30 December 2011
Abstract: The ARCADE 2 Collaboration has recently measured an isotropic radio emission which is significantly brighter than the expected contributions from known extra-galactic sources. The simplest explanation of such excess involves a “new” population of unresolved sources which become the most numerous at very low (observationally unreached) brightness. We investigate this scenario in terms of synchrotron radiation induced by weakly interacting massive particle (WIMP) annihilations or decays in extra-galactic halos. Intriguingly, for light-mass WIMPs with a thermal annihilation cross section, the level of expected radio emission matches the ARCADE observations.
There is also a related news article at Physics World: Radio wave excess could point to dark matter, dated 1 December 2011. This is evidence in the true scientific sense, in that it constitutes a valid inference from observation. The observation is radio emission from outside the galaxy, which cannot yet be explained by any other known sources of radio emission. By itself, of course, the study proves nothing. But like most scientific evidence, it is indicative, it points towards an implied conclusion, which is made explicit in the last sentence of the abstract: We know that physically reasonable, hypothesized dark matter particles, would be expected to generate a radio emission consistent with the radio emission we see. This does not prove that dark matter is responsible for the observed radio emission, which might well have some other source. But it is an intriguing coincidence that what we see so nicely matches what we would expect to see if dark matter were the actual source. It is just one element in an expanding library of evidence favoring the presence of dark matter particles. Each element in the library, by itself, does not amount to much, but taken together, as a whole body of evidence, they have significant implications that scientists cannot meaningfully ignore, as Sebastian seems to think they should.
And while we are on the dark matter trail, here is another recent entry to the lists: The Empirical Case for 10 GeV Dark Matter by Dan Hooper, online preprint: arXiv:1201.1303v1 dated 5 Jan 2012
Abstract: In this article, I summarize and discuss the body of evidence which has accumulated in favor of dark matter in the form of approximately 10 GeV particles. This evidence includes the spectrum and angular distribution of gamma rays from the Galactic Center, the synchrotron emission from the Milky Way's radio filaments, the diffuse synchrotron emission from the Inner Galaxy (the "WMAP Haze") and low-energy signals from the direct detection experiments DAMA/LIBRA, CoGeNT and CRESST-II. This collection of observations can be explained by a relatively light dark matter particle with an annihilation cross section consistent with that predicted for a simple thermal relic (sigma v ~ 10^-26 cm^3/s) and with a distribution in the halo of the Milky Way consistent with that predicted from simulations. Astrophysical explanations for the gamma ray and synchrotron signals, in contrast, have not been successful in accommodating these observations. Similarly, the phase of the annual modulation observed by DAMA/LIBRA (and now supported by CoGeNT) is inconsistent with all known or postulated modulating backgrounds, but are in good agreement with expectations for dark matter scattering. This scenario is consistent with all existing indirect and collider constraints, as well as the constraints placed by CDMS. Consistency with xenon-based experiments can be achieved if the response of liquid xenon to very low-energy nuclear recoils is somewhat suppressed relative to previous evaluations, or if the dark matter possesses different couplings to protons and neutrons.
More evidence, this time a combination of the admittedly ambiguous evidence I already mentioned, from the direct detection experiments, plus observations of radio emission from inside, not outside, the Milky Way, as well as gamma rays. Again, by itself only suggestive, but combined with other evidence it becomes a key player. We see multiple observations, from both laboratory experiments and astronomical observations, all coincidentally consistent with what we would expect to see from dark matter particles.
On the modified gravity front, I said above, "none of them have been able to produce consistency with so wide a collection of observation as the more mundane notion of dark matter". Here is what one researcher from Case Western Reserve University presents:
Modifying Gravity: You Can't Always Get What You Want by Glenn Starkman, online preprint: arXiv:1201.1697 dated 9 Jan 2012
Abstract; The combination of GR and the Standard Model disagrees with numerous observations on scales from our Solar System up. In the concordance model of cosmology, these contradictions are removed or alleviated by the introduction of three completely independent new components of stress-energy -- the inflaton, dark matter, and dark energy. Each of these in its turn is meant to have (or to currently) dominate the dynamics of the universe. There is still no non-gravitational evidence for any of these dark sectors; nor for the required extensions of the standard model. An alternative is to imagine that GR itself must be modified. Certain coincidences of scale even suggest that one might expect not to have to make three independent. Because they must address the most different types of data, attempts to replace dark matter with modified gravity are the most controversial. A phenomenological model (or family of models), Modified Newtonian Dynamics, has, over the last few years seen several covariant realizations. We discuss a number of challenges that any model that seeks to replace dark matter with modified gravity must face: the loss of Birkhoff's Theorem, and the calculational simplifications it implies; the failure to explain clusters, whether static or interacting, and the consequent need to introduce dark matter of some form, whether hot dark matter neutrinos, or dark fields that arise in new sectors of the modified gravity theory; the intrusion of cosmological expansion into the modified force law, that arises precisely because of the coincidence in scale between the centripetal acceleration at which Newtonian gravity fails in galaxies, and the cosmic acceleration. We conclude with the observation that, although modified gravity may indeed manage to replace dark matter, it is likely to do so by becoming or incorporating, a dark matter theory itself.
So Starkman thinks the evident weaknesses of the modified gravity approach are significant enough that, even if we allow that gravity must be modified, we still can't avoid dark matter.
Science is a moving target. There will be more papers after this, more evidence presented as time goes by. Eventually the weight of scientific opinion will come down somewhere, and so far it looks like that somewhere will be the realm of WIMP dark matter, and for pretty good reasons. In light of the evidence, how can anyone sanely argue that the dark matter hypothesis is "beyond scientific verification and falsification"?
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The point of philosophy is to start with something so simple as not to seem worth stating, and to end with something so paradoxical that no one will believe it. -- Bertrand Russell |
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