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Definitions and Limits

  1. Apr 30, 2003 #1

    Ivan Seeking

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    I am going to try for a difficult position here. I intend to question the current definitions of the boundaries of science.

    Scientists [generically] may violate the scientific method constantly in that many popular assertions made by science may not ever be testable. Cosmologists seem to be the easiest target...no offense intended. How can we ever reproduce the Big Bang for example? If we can never make one, and we can never test the theory in any direct and real way, it seems that by definition the theory does not qualify as science. Another example may be “dark energy”. What if this stuff cannot be made or measured directly? Could the stuff that dominates the universe exist outside of the reach of science? Have we ever seen a planet evolve, or are all theories of planetary evolution based on inference…that goes for earth also? Furthermore, it seems to me that if we are ever to have a complete description of reality, all theories must somehow merge into a directly testable hypothesis. It doesn’t seem likely that we can have a unified theory that fails to explain all of existence. If all of existence can never be tested, isn’t the greatly anticipated grand unified, or TOE or M theory forced into the category of philosophy…by definition?

    I don’t mean to be nit-picking here. I think this question comes with serious scientific implications, and more generally, it poses credibility problems with respect to public perception. Personally, I find the lack of confidence in physics - especially among many engineers – appalling. In many cases, the perception of the credibility of physics has already swung against us! I think this partly result from a heavily biased Newton-like perspective posited by some, taken in contrast to the almost metaphysical underpinnings of quantum mechanics. I’ve been reading and studying this stuff for years. Sometimes I can hardly tell where the physics ends and the BS begins…in either direction!
     
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  3. Apr 30, 2003 #2

    mathman

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    You're being too pessimistic. Reproduceability is not necessary for an idea to be testable. The big bang idea is tested on the certain facts of the current universe, the cosmic background radiation, the amount of Deuterium, etc. If someone would propose an alternative theory consistent with these observations, scientists would try to look for something where the theories would disagree. As for dark energy, it is not the only theory out there to explain the speeding up of expansion.
     
  4. Apr 30, 2003 #3
    Yes I agree with mathman. And gleefully, what if the concept of time is not the time that we really know of, but instead permits time travelling or past-present-future simultaneity or if we can somehow "come out" of the time dimension and into a higher dimension etc, then, any cosmological idea can be proved directly enough.
    Just a thought.

    Quantum physics is our hope ...

    http://www.sciam.com/article.cfm?colID=1&articleID=000F1EDD-B48A-1E90-8EA5809EC5880000
     
  5. Apr 30, 2003 #4

    Ivan Seeking

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    The dark energy example was a weak choice since we know so little about it...if it is there. But, do we have a working theory of Cosmology that can never be directly tested? Could our world view be fallacious like the Pre-Keplerian epi-cycles of Mars? Now there is a clear example of something that explained observations of the time, but was still completely wrong.

    Maybe you can help to clarify things in this way. What exactly is the difference between philosophical and scientific inference? Is there one? Exactly when do we know something, and when are we only supposing; and how do we gauge how much we are supposing? How well is this reflected in the literature? Also, consider all of the assumption for any given hypothesis? I suspect it would be very difficult to even identify all of them. .

    Shouldn't the first sentences in every Cosmology or Astronomy book read something like: "What follows is a hypothetical model that is supported by the evidence but that can never be fully tested”, Or, ”Other world views could be valid."? Without worrying about the semantics of how best to convey this, science has stepped from one revolutionary paradigm change to another. The fact is: We will likely see another. No paradigm [world view] seems to implicitly recognize this. I am trying to get at the philosophical assumptions that are the basis of science. Are physicists also philosophers? I don’t think they can help themselves…but most don’t see it that way.
     
  6. May 1, 2003 #5

    mathman

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    Your caveat is true of all science (as opposed to religion) - so what!
     
  7. May 1, 2003 #6

    Ivan Seeking

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    Please don't misunderstand, I am trying to get to an elusive point, for me at least, and I don't mean to offend anyone here:

    It seems like some areas of science require and provide for a more rigorous level of proof than others. This seems to be the nature of the beast since we can't readily make planets or galaxies or universes. Still, there is a big difference between predicting and then detecting the existence of a quark, even if indirectly, and predicting [but never possibly making] a 12 or 11 dimensional hypersurface that could predate the Big Bang. It seems to me that in a fundamental way we have crossed the abyss into philosophy. In spite of the definitions involved, we don’t interpret things in this way. Where exactly is the line between a testable theory and one that can only be inferred. How many levels of inference constitute a leap into philosophy? Even detecting a quark requires inferences.
     
  8. May 1, 2003 #7
    One of the methodology of science is to have a falsifiable theory as claimed by Karl Popper. I've to agree to an extent with the science philosophers on the weaknesses of science but even so, these philosophers are also theorizing and their judgements on science may be wrong in future.

    Nevertheless, even if we are to accept that some theories as in cosmology are not fully testable or we can't see quarks, what is more important are the outcomes of the theories, ie are they according to nature, if it is then why bother looking for another theory which also predicts the same things but using different concepts? Since scientific theories are subjected to Popper's falsification process, can we say that we will eventually come to "one of" the right theory among multiple equally correct theories to explain nature? And if that theory is used to talk on cosmo, why shouldn't it come out to have a right prediction?

    Hope I've conveyed my idea in words. Communications in numbers is easier.
     
  9. May 1, 2003 #8

    Ivan Seeking

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    Good points. But with respect to the specific statement quoted above: You employ a "philosophy" which immediately "pre-supposes" and sets "artificial limits" on the value of "truth" and the potential for "wisdom". [I bet you didn't mean to do all of that] Simply put, how do you know it won't make a difference? [?]

    EDIT: Mathman thinks I am being too pesimistic. I guess this could be summed up as: How much certainty can we assign to such grand theories that cannot be directly tested? How does this compare to our certainty [of the predictive ability or the "correctness"] of other branches of physics like Classical Mechanics...as an extreme comparison?
     
    Last edited: May 2, 2003
  10. May 2, 2003 #9
    Any decision in daily lives involves the amount of information we have prior to making a decision, even philosophers. Our decision is ALWAYS based on the assumption that the information that we have are correct and sufficient enough. If in the end, our decision turns out to be incorrect, we would know that our assumptions have been wrong. Then we go searching for where have it gone wrong ... So is science. Eventually, as emphasized, science will explain nature. Any "truth" claimed which cannot be ULTIMATELY (i said ultimately) be explained by science and has not affect us in anyway cannot be considered "truth".

    Scientific theories are assumptions based on what we have known so far and their subtlety to falsification is abundant. No theories is claimed correct fully, however, theories are tools which generates ideas after ideas for the quest of nature finding.

    An analogy: if we know that we add numbers together when we have a + sign as a theory, how much certainty do we have that 1 + 117 = 118?
    => Relativity and quantum physics are theories, and cosmology is 1 + 117 = 118. If adding numbers when we see + sign is false, is 1 + 117 = 118?
     
  11. May 3, 2003 #10
    It is not generally accepted in the science community that all scientific theory should fit the description of Popper (i.e. that any scientific theory can be falsifiable).
    Remember that the "theory of falsification of scientific theories" is a scientific theory itself. so it bites itself in the tail so to say.
    If we can come up with only one scientific theory that is not falsifiable, but still is a scientific theory, it means that the scientific theory of the falsification itself is falsified (and thus proved wrong).
     
  12. May 3, 2003 #11
    In a strict context as perceived by Popper, yes, the falsification process is not the best. In one arguement taken to "fire" this process was the Newton's theory. It failed microscopically but still can be used daily.

    In this view, I think that the falsification process taken loosely is to weed out experimentally non-compatible theories. After all, this is the way scientific theories are developed - to be persistent with existing data and to be able to predict new ones. However, when two competing theories like Newton's and Einstein's are capable to predict macroscopic non-approaching light speed phenomena, and we know that at light speed only Einstein's explanation is the best to this day, our conclusion is that EGR is a better explanation of nature but of its complexity in calculation, it's better to use Newton's for macroscopic work to the permitted accuracy.

    What examples can you give? All scientific theories must be persistent with existing datas and be able to predict new ones ... isn't this falsification is a loose manner not the restricted one by Popper?
     
  13. May 4, 2003 #12

    Ivan Seeking

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    I understand the objections and I still can't quite wring out the proper context here. I suggest the following link and especially the survey results at the end. This I hope conveys the ambiguity that I refer to; and I hope a sense of my objection to the philosophical framework of modern physics. Perhaps I am really arguing for a stronger philosophical perspective in physics.

    Here is your philosophy
     
  14. May 4, 2003 #13
    Science is just huge set of methodologies to avoid getting lost in mud.

    I'll paraphrase one imo good view:
    Artist drawing a picture: Given a system of one billion combinations of which only one million are desirable, find one.
    Scientist: Given a system of one billion possibilities and one unique solution, find that one.
    Research mathematician: Construct a System or process which will account for the one billion possibilities.

    Well, there are billions of possibilities, how do we know them? Nth degree of speculation creates billions of possibilites.

    Thus, scientists are creating billions of (crackpot) theories and then falsifying them one by one until what remains must be true. If theory is not falsifiable (like god created everything), then its not scientific. If it uses invalid reasoning, then its false before even testing. Majority of them don't even leave the head.

    Then, there are theories, and there are interpretations. Interpretations need not all be tested. If key-points of theory are tested, then it stands true. Theories are usually compact mathmatical solutions. When interpreting them, unavoidably philosophy cuts in. Paradigm dictates pretty much how interpretation goes.

    Imo, science at times fails to find unique solution from billions of possibilities. To solve the embarrasment, it goes ahead and tries to construct a system that accounts for all of them. Probably its possible to construct mathmatical model for just about anything, detached from actual reality (strings). To get things into perspective, one needs philosophy. When true theory does not fit into paradigm, it might get discarded as "physically meaningless". To get there, at times paradigm has to change. And its damn difficult.

    In all, I think that scientists are in the end the biggest philosophers, only that scientific methods constrain them alot. The sad part is that there is also strong force of authority, that basically keeps foundations solid, but is in essence dogmatic. Its beatable, but at times may stop paradigm shift for ages.
     
  15. May 4, 2003 #14
    No, and for that I thank God every day. :smile: I tend to view 'scientific method' as being like pornography -- I can't define it, but I know it when I see it. All attempts to define it (cf the entire philosophy of science) generally end up looking rather silly. And when you get right down to it, I can't think of a single example where these kind of abstruse metaphysical debates about philosophical frameworks would make any important difference in the actual practice of physics.
     
  16. May 5, 2003 #15

    Ivan Seeking

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    Out hidden philosophies determine our expectations about reality. This in turn determines the theories that we propose - to explain observations and the way that we interpret these observations. If such strangeness were anticipated, perhaps we would have conceived of QM in 1700 instead of 1920. We had Newton and Huygens to figure it out but the philosophy was just beyond them.

    Consider the philosophical impact when Einstein first proposed time dilation. How can we argue that our failure to consider this idea at some earlier time was not a direct result of our philosophical expectations? The insight that Einstein gives us is philosophical. We now accept these ideas so readily that this point is seemingly lost. Relativity was a huge leap in philosophy followed by the addition of some rather inconsequential equations. Without the applied philosophy, the equations are useless and meaningless. To argue against this is in itself a philosophical proposition. How can we avoid the stuff?

    EPR, Schrödinger’s Cat, Heisenberg, DeBroglie, The Measurement Problem, Entanglement, and many other examples exist where our expectations clearly play a significant role in our ability to handle the paradoxes that nature seems to favor.
     
  17. May 5, 2003 #16
    Relativity or quantum physics could not be discovered in Newton times, because both come from experiments, and in 17 century experiments were not as accurate yet.

    (Philosophy, as you can see, did NOT predict relativity NOR quantum theory. Philosophy just had to follow these discoveries.)
     
  18. May 5, 2003 #17

    DrChinese

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    I am not sure I understand your comment about the credibility of physics. It's not like quantum mechanics is not providing ever more accurate answers to ever more detail questions. Quite the opposite, physics had advanced to the point that it is beginning to address questions that were once considered unanswerable. Perhaps this is the point you were trying to address in the post - conditions at the boundaries of knowledge.

    At the boundaries, we are asking questions we may never know the answers to. Nothing wrong with that anyway - unless something is claimed which is hype. "Are there other universes besides our own?" for example. True, current physics cannot answer this question, so it exists in the realm of the philosophical (or religious). But I don't see how this is much of a criticism, and I don't see that scientists are violating the scientific method by probing the boundaries of our knowledge.

    Can you provide a specific example to discuss? One in which a scientist is "generally violating the scientific method"?
     
  19. May 5, 2003 #18

    DrChinese

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    OK, I agree with your statements. But some people are able to think outside the box earlier and more clearly than others. This is why Nobels are awarded. It is still incumbent on anyone on anyone who is proposing a better theory to demonstrate some way in which it is better or more useful. Physics is able to apply the scientific method nicely in this regard.

    On the other hand, I prefer to point the finger at the science of psychology. Now there is an area in which the scientific method is really running amuck! There is currently no generally accepted master theory of human behavior to help guide new study. What advances have been made there in the past 50 years?
     
  20. May 5, 2003 #19

    Ivan Seeking

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    I really meant to refer to the concept of superposition. The wave particle paradox was known and remained for the next 200 years. The simple answer that something could somehow "exist" as both was beyond the philosophy of the time. We had implicitly ruled out this possibility.

    Relativity was not predicted or deduced by using the scientific method. A leap of thought produced the whole thing...a leap outside of the philosophical boundaries of reality.
     
  21. May 5, 2003 #20

    Ivan Seeking

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    Re: Re: Definitions and Limits

    You are right of course. I intended to spin this differently and probably should not have included this point in this discussion. In the end, I will only say here that to many people, many people whose tax dollars support physics programs, the apparent schizophrenia in physics - resulting from the incredible level of disagreement about fundamental questions - causes a lack of faith in the whole process. I know this because I am constantly faced with attacks from engineers and other technical and non-technical people - not about a discussion like this one of course, but about commonly accepted ideas. [Understand that in this thread and others I am intentionally assuming an unpopular position and throwing my most vulnerable arguments on the table.].

    Yes.

    I really mean to argue just the opposite here. However, the scientific method implicitly makes many assumptions. These assumptions go mostly without recognition. If one brings them up, most physicists find it annoying or irrelevant. What I meant to demonstrate is that we constantly cross the line into philosophy. We form a philosophical premise - a hypothesis – and we make a prediction – our philosophy - and then we see if more testing provides further evidence for our philosophy. I think that this philosophical process is the essence of science. Others argue that it not philosophical, ergo philosophy has nothing to do with science. The statement in itself suggests a proof for the opposite argument. We are making a philosophical assertion that philosophy is irrelevant?

    However, considering a more quantifiable aspect of this idea, and as mentioned earlier in this thread, I wonder how many levels of inference constitute a leap into philosophy. When do we have so many assumptions buried in a theory that until direct evidence can be produced, we are really still in the realm of a philosophical assertion? I suggest Classical Mechanics as a baseline for comparison. Furthermore, what really is our level of certainty about a "theory of everything" when we still can't define or agree on what constitutes a measurement.

    Here is the point I am trying to make. I can demonstrate what I meant as soon as type the word that I have in mind. ufo. What was your reaction? I don’t draw conclusions here. I bet most of you did. Didn’t the mere mention of the word bring a conclusion to your mind…uh oh! It does for many scientists. Now I don’t mean to argue for aliens here, I do argue that ufos justify further investigation. I make this argument in the pseudo-science ufo thread. Please see my last post for a summary of my position on this subject.

    Here is why I am sure about this argument…why I “believe” what I am saying. [i'm not talking ufos here] I won’t give the details here because I can’t prove anything. I only have my own experience and there’s nothing that I can do about that. But, I have experienced one inexplicable phenomenon in my life. I know with certainty what I experienced. When I hear scientists who happen to comment on this subject I almost have to laugh. I have the conviction of certainty…as least as much as we do with any normal everyday experience. When science asks for the evidence of such events, my response is: Why don’t you help to find some? We don’t because we make too many assumptions. I can now only wonder how many other truths we are missing because of our philosophy.
     
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