A constant speed of light in all reference frames? Surely you can't be serious.
in [Relativity]
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From: PD on 2 Mar 2010 11:38 On Mar 1, 7:40 pm, Ste <ste_ro...(a)hotmail.com> wrote: > On 1 Mar, 16:12, PD <thedraperfam...(a)gmail.com> wrote: > > > > > On Feb 28, 2:37 am, Ste <ste_ro...(a)hotmail.com> wrote: > > > > On 27 Feb, 16:10, PD <thedraperfam...(a)gmail.com> wrote: > > > > > On Feb 26, 7:15 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > On 26 Feb, 18:14, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > On Feb 25, 10:47 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > > You have then questioned why you should adopt the scientific metric > > > > > > for "working". And the answer is, you don't have to. It's just that > > > > > > when you decline, you're no longer doing science. > > > > > > But this lends credibility to my assertion in the first place, which > > > > > is that science is a religion. > > > > > No more than the practice of law, medicine, music, architecture, or > > > > plumbing, as we've discussed. > > > > Practitioners of law and medicine are undoubtedly ideological. > > > And so law is a religion? > > And medicine is a religion? > > Not in my understanding of the word religion. > > To go back to my original formulation of this issue, the question is > whether science, scientists, and adherents of science more generally, > have the same hallmarks as traditional religions, theologians, and > religious believers more generally. These are not questions of the > supposed scientific method, but of the psychology and sociology of how > science is actually practiced. In the same way that the question of > how Christianity has been in fact practiced is not determined by > reference to the Bible. > > To start asking questions like "is law a religion" or "is medicine a > religion" is like asking whether canon law "was a religion", or > whether faith healers "are a religion", and of course the answer is > no. Canon law is informed by religious belief, and faith healers are > religious, but neither of them alone comprise "a religion". > > Also, my point here is not to get into a long (and surely fruitless) > debate of arguing how exactly religion is defined. My point is that, > from a social and psychological perspective, an adherence to science > cannot be distinguished from religious belief in any meaningful and > significant way, and that the supposed differences tend to be either > based on a misapprehension of what function religion actually > performed and how it was practiced in the past, or on a literal appeal > to concepts like "the scientific method" that bears little > correspondence to how science is really practiced. It is certainly possible to find similarities in how science is conducted and how religion is conducted. This does not make science a religion, any more than a cow and a turtle both having four legs and a tail would make mammals reptiles. This was the point of my statement about law and medicine, which also show similarities in conduct between those pursuits and religion, but this does not make law a religion or medicine a religion. Mammals are distinguished from reptiles by having features that reptiles lack. It does no good to point to the four legs and a tail and comment that, no matter what mammals have, they still have four legs and a tail and so that makes them resemble reptiles. Likewise, though you dismiss the scientific method as a distinguishing trait and choose to focus on the practices that make them seem like religion to you, this does not make science a religion, just by your choice of what will occupy your attention. > > > > > You've said those are different because the stakes are somehow higher > > > > with science. I also disputed that. > > > > Did I say that? I don't recall saying that, and if I did say it I can > > > only imagine it was said in a different context. > > > You said that plumbing and architecture make no claims about the > > fundamental nature of the universe, implying that this somehow excuses > > them where physics should not be. > > What I meant, if I remember correctly, was simply that plumbing and > architecture don't make claims as to their own "truth" or the truth of > anything else, and especially not the kind of truth that has any > sociological relevance. I disagree. Plumbing adheres to standards because it is the established truth that following those standards will ensure safety and effective operation for a decent amount of time. I don't consider this to be any less of a "truth" than the "truth" you think that science provides. Science is no more sacrosanct or fundamental than architecture or ethics, and I have no idea why you think it does. > > > > > Just because there is an agreed-upon methodology by the collective > > > > that practices in the discipline does not warrant that discipline > > > > being called a religion, at least as I understand the meaning of > > > > "religion". > > > > There is more to religion than an "agreed-upon methodology", but there > > > is more to the practice of science than this, too. > > > Then you'll have to be precise about your meaning of the word > > "religion" and therefore how it is that science satisfies it. > > I personally think it's more convenient to compare and contrast, > rather than trying to establish a definition for either religion or > science. Indeed, attempts to establish a consistent definition of > science, by men better than me, have time and again died a thousand > deaths. By that approach, one could easily be convinced that cows are reptiles, no?
From: PD on 2 Mar 2010 11:48 On Mar 2, 5:09 am, Ste <ste_ro...(a)hotmail.com> wrote: > On 1 Mar, 23:39, PD <thedraperfam...(a)gmail.com> wrote: > > > On Mar 1, 4:39 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > You see, it is not at all obvious that there is a "gravity" at all, > > though the effects that we would attribute to gravity are certainly > > there. But perhaps there is no physical gravity at all. As you say, no > > one --- including you --- would be able to supply any undeniable > > description of gravity other than by virtue of its effects. Newton did > > not attempt. Thus it is open whether there is any such "thing" at all. > > I agree. Personally I'd put money on gravity being a manifestation of > electromagnetism, but that is besides the point. This has been looked at, and extensively! Einstein himself made a go of it. It might be worth your time looking into what came of those efforts. It's not hard to look up. Here, I'll give you a starter: Kaluza-Klein. > > > > The fact that no one here seems to be able to give an answer is to me > > > evidence that some people here don't really know, or certainly don't > > > have a well-developed and well-thought-out knowledge of what Minkowski > > > actually means. > > > I don't know why you would conclude that. If you stood on a street > > corner on London, near a busy taxi stand, and demanded that someone > > explain alternation of generations in plants, and no one responded to > > you, would you be right in concluding that none of the people at the > > taxi stand have well-thought-out knowledge of alternation of > > generations in plants? Would it be true even if the taxi stand was > > outside a conference of biologists and you were doing the same? > > It has to be a judgment Paul, but when people are willing to spend a > lot of time claiming to know all about SR, but are not willing to > spend any time explaining it, then one has to ask whether they > actually know what they claim to know. I disagree. That judgment is certainly influenced by your choice of venue and the interpersonal relationship implicit in the conversation, as to whether an explanation is a reasonable expectation. This is what I've been suggesting to you: that if you enter into an explicit student-teacher arrangement, you will certainly be given the explanation you seek. If you look for an explanation in an open discussion forum where this arrangement is not implicit, then you might well be leaping to the wrong conclusion if you do not get it. Do you mine for jewels in your garden, too? > > It is one thing to waylay a biologist in the street and be told "This > is the way it is, but I'm afraid I do not have more time to explain. > Good day to you, Sir", but I do not think those are the circumstances > here. I don't know why you'd think differently here. You've been told repeatedly that this is the way it is, but that it is not worth the time to explain it here, but here incidentally are some excellent recommendations for readings that you can plunder at your leisure. Somehow this clear response to you has been ignored or taken to be unacceptable or somehow indicative of lack of expertise among the people here. > > In any event, I don't want to get into a long discussion about what > factors I take into account in making such a judgment. Inevitably, I'm > drawing on a lifetime of interpersonal experience and donkey's years > of using discussion boards and newsgroups, and one naturally acquires > an intuition for other people's psychology. Likewise. And I'm telling you that in this group, you are getting exactly what this group has consistently provided to people exactly like you.
From: Vern on 2 Mar 2010 11:58 On Mar 2, 4:05 am, "Peter Webb" <webbfam...(a)DIESPAMDIEoptusnet.com.au> wrote: > "Paul Stowe" <theaether...(a)gmail.com> wrote in message <snip> > Newton was 'smart enough' to realize that this gravitational force > equation was simply a quantifying correlation and not a physical model > or explanation for gravity. The famous quote "hypothesis non-fingo" > said it all! You don't seem to grasp the fact that both GR and > Newton's equations provide no physical model or basis for their > existence. In the case of Newton his equation is mute on many aspects > of gravity like its speed of propagation as one example, so-called > frame dragging for another. Einstein was also smart enough to realise > that GR also needed so physical framework. But what I call the modern > science blindness does not realize that equations ARE NOT! physical > explanations they are, instead, the way such physical model are > quantified. Yes, you can correlate observed behavior to equations and > have those equations match observation. You can even further predict > that future observation must match the form but still be totally > ignorant of proper physical basis, tolemy's system is a classic > example of this. I would put Minkowski equation in the Ptolemic > category, not wrong, but not useful to understanding the underlying > physical process either. It is neat mathematical format which takes > advantage of a physical property but without any knowledge or basis of > what brings about that property. > > _____________________________ > Like the E and M fields in Maxwell, or the force of gravity in Newton? Yes, unless you realize that both are medium effects. Paul's comments are based on that realization. Vern
From: PD on 2 Mar 2010 11:59 On Mar 2, 5:53 am, Ste <ste_ro...(a)hotmail.com> wrote: > On 1 Mar, 23:49, PD <thedraperfam...(a)gmail.com> wrote: > > > > > On Mar 1, 5:33 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > secondly > > > > > the degree to which opponents seem to be unclear about the conceptual/ > > > > > qualitative basis of SR, > > > > > I'd be careful about this. It may be that they are clear on the > > > > conceptual/qualitative basis, but are declining to present it to you, > > > > out of a personal preference for using the clarity and condensed > > > > efficiency of mathematics. This unwillingness to cater to your > > > > pedagogical needs should not be construed as their being unclear. > > > > Paul, there is nothing "clear and efficient" about mathematical > > > statements made without any indication as to their meaning. > > > Yes, there is, for people who have learned that skill. This is one of > > the reasons why the skill is so important for physicists to learn -- > > because it so promotes clear and efficient communication among those > > so trained. > > Not, as I say, if the discussion is at a qualitative, conceptual > level. And I've told you this is wrong. Because.... > Maths in that event becomes utterly useless, because it does > not describe phenomena qualitatively - in fact it quantifies phenomena > that have already been (explicitly or implicitly) described > qualitatively. .... there is much qualitative information in the math itself, which is obvious to people who are experience in reading math. I've told you repeatedly that there is physical content in the mathematical formulation of physics, and I've even given you a few examples in the past, which you admitted you had not appreciated. > > > Likewise, auto mechanics is so much simpler for people who have the > > right toolbox and know how to use them, and auto mechanics are not > > very inclined to teach someone how to service cars if all they know > > how to use is a spanner and a screwdriver. > > It really depends. Good luck with that. > > > > > > The > > > argument here is not about the mathematical form of SR, but about its > > > physical meaning. I'm willing to concede that certain posters may be > > > unaccustomed to discussing anything but maths, and may therefore find > > > it difficult to articulate the relevant information, and that's an > > > allowance that must be made, but that's not a preference for being > > > "clear and efficient" - in fact the effect is to make much of what is > > > written utterly obscure and ineffectual.' > > > For those that are not so trained, it IS utterly obscure and > > ineffectual. But then accomplishing the task of explanation *overall* > > is optimized if you do learn that skill, because the gain in > > efficiency following learning the skill more than offsets the burden > > of learning the skill in the first place. It's like learning how to > > play music and the requirement that you read music. You CAN learn > > musical pieces without learning how to read music -- it's just not > > recommended. > > More to the point, one can understand the principles of music without > reading music or being able to play an instrument with any real > aptitude. Yes, but laboriously and poorly, and the teacher may be quite irritated at having to explain the principles of music without the benefit of being able to point to a sheet of music and say, "See? Here is where the minor third is resolved over the course of four measures, accompanied a half-measure behind by this fugue passage." Again, it is *possible* to understand physics qualitatively without the math. But laboriously and poorly, and teachers will find it less than efficient to teach that way, when it would be much easier to produce the desired result after some skill training. Your reluctance to spend the effort on the skill notwithstanding. > The discussions here have followed a script something like > "Q: how does the instrument make the sound. A: Oh, well, I can't > explain that unless you know how to read music." The problem is that > there seems to be some disagreement about whether knowing maths is > essential to describing physics qualitatively, and it is my contention > that it isn't. > > To explain why supposed experts here take a different view, I can only > conclude that they don't really understand the nature of my questions > - the evidence to support this conclusion is, for example, the fact > that no one here seems to know immediately what the word "physical" > means when I and others have used the word. This makes me less > confident in trusting those who say that learning the maths will > answer my questions. That's an erroneous conclusion. > > > I understand that you JUST DON'T WANT to learn that skill. > > It's that I'm not interested in learning the skill for its own sake, > or worse on the false pretense that it will actually answer any > questions. > > > However, > > this then asks people to use a relatively inefficient means to > > communicate the physics to accommodate this disability. > > No. Yes. > > > > > > and thirdly the preconceptions and > > > > > psychological style of many posters. > > > > > In other words, your basis for deciding what is correct depends on the > > > > manners of the people you discuss it with? > > > > No, I'm saying some of the personalities that one must grapple with > > > here are not the sort of personalities who make good discussion > > > partners. Indeed many posters seem to have preconceptions or styles > > > that are designed to avoid or deter productive discussion and sharing > > > of knowledge. > > > Indeed. I think you'll find that the university environment, where > > discussion partners have placed themselves in the position of being > > more friendly and accommodating, is more productive. > > That may well be the case, but inevitably I don't have casual access > to a university environment, or the inclination to follow a course of > study in physics, most of which I would have absolutely no interest > in. That's fine. But that does not imply that you should expect to get what you want, avoiding the unpleasantnesses and inconveniences, in a venue that you choose, for free. > > > > > > > I'm sorry, but I've got a lot of classroom experience that shows that > > > > this is simply a bogus expectation. I can set up a series of simple > > > > experiments on a daily basis in class where I can display all the > > > > elements of the experiment and show them plainly how the simple set-up > > > > is put together, and then I can ask everyone in the class what their > > > > intuition tells them will happen, and at least have of them will get > > > > it wrong, which the subsequent observation will show. > > > > Yes, because there is a discrepancy between intuition and observation.. > > > But as I say, there is no room for a discrepancy - in the sense of > > > "this town ain't big enough for the both of us" - and inevitably > > > intuition is the one which must leave town (which in practice means > > > either refining an existing intuition, or overhauling it to a greater > > > or lesser degree). > > > Exactly. And so when you say that what I described just isn't > > "realistic" according to your intuition, then it is your intuition > > that needs to be overhauled. > > Just because someone else *says* something is irreconcilable with > intuition, does not mean intuition must be immediately overhauled. I agree! One needs to either see it experimentally for oneself, or to become thoroughly acquainted with the experimental work done by others! That is the essential and indispensable ingredient in being convinced that one's intuition is just off the mark, and nothing else will substitute. > If > I had done that, for example, when people said "what is simultaneous > in one frame is not simultaneous in another", then I'd have thrown > away perfectly legitimate intuitions which said that this statement > was wrong. > > > > > > > Yes, I see what you are thinking of. And it is true that IN THIS CASE, > > > > E1 and E2 will be viewed as simultaneous by both observers. I do > > > > concede this. > > > > > This is not the situation we were discussing before, however. > > > > I wasn't talking about the train case. I was talking about this > > > specific scenario, which I had posted before, and which last time > > > indeed you conceded without fuss. > > > > But for some reason everyone, including you apparently[1] but > > > certainly not limited to just you, seemed to go back to talking about > > > "what is simultaneous in one frame is not simultaneous in another", > > > when in fact the veracity of that statement is contingent on the > > > circumstances, and there are in fact cases (i.e. the one above) where > > > what is simultaneous in one frame *is* simultaneous in another. It is > > > that contingency that allows reconciliation with my intuitions. > > > > [1] I quote you from above "It is very much true in SR that two > > > spatially separated events that are simultaneous in one frame are not > > > simultaneous in another frame moving relative to the first". > > > I've already noted to you that the statement I made is not accurate > > and needs revision, which I'm happy to do. > > That's fair enough, but hence I've found that my intuitions were, at > least in this respect, in agreement with your understanding all along. > > Now that is cleared up, what I'm still not clear about is whether this > non-simultaneity is a mere function of finite propagation speeds, or > something else. It is not a function of finite propagation speeds, this we know, because we took into account the finite propagation speeds in our procedure for determining simultaneity/nonsimultaneity. Do you not remember that?
From: Ste on 2 Mar 2010 12:01
On 2 Mar, 16:23, PD <thedraperfam...(a)gmail.com> wrote: > On Mar 1, 5:53 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > Yes, and that is done by self-selection. In the community of > > > > > scientists, the presumption is that open questions will be addressed > > > > > by someone eventually. And there is reward in the community for that > > > > > adventurism. The assessment of the risk vs benefit of the adventurism > > > > > is made individually. > > > > > Indeed. But it is then a sociological question, to ask which > > > > scientific questions are answered and which are not, and why. > > > > That's true. What I just stated is that the presumption is that > > > essentially all questions get answered eventually. > > > Perhaps, but the question is "in what circumstances". > > That depends. There's no clean answer I can muster. Why is it > important to have one? The answer is important in order to verify that science is in fact likely to deliver the goods that it claims to be able to deliver. Unless, of course, proof denies faith. And if science is not likely to deliver the goods, then it's useful to know ahead of time. |