A constant speed of light in all reference frames? Surely you can't be serious.
in [Relativity]
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From: Ste on 2 Mar 2010 10:07 On 2 Mar, 12:22, "Inertial" <relativ...(a)rest.com> wrote: > "Ste" <ste_ro...(a)hotmail.com> wrote in message > > news:826536ad-6078-4cd4-a2d1-61b25bec5bf0(a)k17g2000yqb.googlegroups.com... > > > > > > > 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. 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. > > >> 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. > > >> > 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. 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. > > >> 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. > > >> > > > 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. > > >> > > 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. If > > I had done that, for example, when people said "what is simultaneous > > in one frame is not simultaneous in another", > > Which in general is correct. There is a particular set of exceptions. > Whoever phrased it that way was a little sloppy. More than one person here has phrased it that way, and they have done so on more than one occasion. Even, in Paul's case, having previously conceded that the statement was inaccurate. > > then I'd have thrown > > away perfectly legitimate intuitions > > Not perfectly legitimate at all .. your ideas about simultaneity are very > much wrong. Well, we'll see. > > which said that this statement > > was wrong. > > It wasn't absolutely wrong .. it just wasn't *always* right .. there was a > relatively small exception case. It was more often right than wrong. You seem to get the point. My intuitions *already tell me* when this statement is right and when it is wrong. But I've been blasted for relying on these intuitions when, we now find out, they are in fact correct. > You STILL do not understand the simultaneity issue, and rather seem more > interested in discussing what you see as the shortcomings of science than > fixing the shortcomings in your understanding of it. > > If you wish to learn, there are many here, including me, who will help you. > You just seem more interested in gloating than learning. We'll there's no point raking over the issues a second time. We accept there is a common understanding between us about the situations where non-simultaneity manifests. Next, what is the fundamental cause (confining ourselves to SR) of this non-simultaneity? As I say, as far as I can tell, it's a simple function of the finite speed of propagation. But I'm told that it isn't, so I need to know on what grounds a simple propagation explanation does not suffice.
From: PD on 2 Mar 2010 11:23 On Mar 1, 5:53 pm, Ste <ste_ro...(a)hotmail.com> wrote: > On 1 Mar, 15:50, PD <thedraperfam...(a)gmail.com> wrote: > > > > > On Feb 28, 1:05 am, Ste <ste_ro...(a)hotmail.com> wrote: > > > > On 27 Feb, 15:58, PD <thedraperfam...(a)gmail.com> wrote: > > > > > On Feb 26, 6:59 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > > There's a variety of things one can do (and are done). > > > > > > 1) Explore other candidates, though at a level that is commensurate > > > > > > with risk-benefit analysis of the effort involved. > > > > > > 2) Continue to do other tests of this model vs other models to see > > > > > > where the 5% might lead (to either opening it up to 40% or closing it > > > > > > to 98%, say) > > > > > > 3) Let the community by itself determine organically which volunteers > > > > > > from the community will plumb the 5% doubt. > > > > > > 4) Design a bunch of devices that are based on a 95% assurance that > > > > > > the principles of that model are correct, again weighing risk vs > > > > > > benefit on the chance this is a mistake. > > > > > > That's fair enough in abstract. But the question is still who pursues > > > > > which avenue, and what subjective perception they have of the > > > > > likelihood of a particular theory being correct. > > > > > 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?
From: PD on 2 Mar 2010 11:25 On Mar 1, 6:00 pm, Ste <ste_ro...(a)hotmail.com> wrote: > On 1 Mar, 16:28, PD <thedraperfam...(a)gmail.com> wrote: > > > > > On Feb 28, 11:33 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > On 28 Feb, 17:20, Bruce Richmond <bsr3...(a)my-deja.com> wrote: > > > > > On Feb 27, 8:42 am, Jerry <Cephalobus_alie...(a)comcast.net> wrote: > > > > > > You should give Ste a specific book recommendation: > > > > > > Spacetime Physics, by Taylor and Wheeler > > > > > > The second edition can generally be picked up used for about $25. > > > > > The first edition is frequently found on eBay with a "Buy it now" > > > > > price of $5 to $10. > > > > > [...] > > > > > IMO that book stinks for explaining SR. It presents the math but > > > > doesn't provide the underlying reason for the math. > > > > Haha! And these pillocks wonder why I won't go out and spend a grand > > > in money and 6 months of time, working through their extensive reading > > > lists! > > > Ah, so you're looking for a reference that is GUARANTEED by universal > > acclamation to satisfy your learning needs? > > No, I'm simply justifying my failure to "work through this reading > list"/"go back to education"/"learn some maths", when it my > apprehension at the outset that embarking on these courses of action > would not have resolved my questions, but would simply have wasted my > time and money. And hence, when I say I want to discuss things instead > of just going off and reading a book, it's not because I'm being > awkward or just want to sound off cranky ideas to an audience, but > because I genuinely apprehend that the interactive discussion is > necessary for the questions at hand. OK, I do appreciate the value of an interactive discussion. That's why a college environment with a live, interactive, engaging teacher is well-suited to this purpose, especially since in such an environment, the teacher will take care to define terms carefully and to give you access to supporting materials. Note the contrast with the poor choice you've made here. But feel free to flog the dead horse and curse it for not getting up.
From: PD on 2 Mar 2010 11:27 On Mar 1, 6:10 pm, Ste <ste_ro...(a)hotmail.com> wrote: > On 1 Mar, 17:14, mpalenik <markpale...(a)gmail.com> wrote: > > > > > On Mar 1, 8:51 am, "Peter Webb" <webbfam...(a)DIESPAMDIEoptusnet.com..au> > > wrote: > > > > >> > Stop making me laugh Peter. I have surely forgotten more about > > > >> > evolution than you'll ever know, because you typify arrogance and > > > >> > closed-mindedness. > > > > >> I laughed when you first said what you thought evolution was about.. > > > > >> You said it explained the origon of life (amongst other things). > > > > >> Evolution says nothing about that at all. > > > > > Guffaw! "Evolution says nothing about the origin of life at all". I > > > > wonder if Dirk van de Moortel would like that one for his "immortal > > > > fumbles" page. > > > > Interesting that you have forgotten more about evolution than I will ever > > > know, because I can't actually recall Darwin's theory of evolution as saying > > > anything at all about the origins of life. > > > > What do you think it says about the origins of life, exactly? > > > > (See. Like I said. You know even less about evolution than you do about SR.) > > > Peter, here you go:http://en.wikipedia.org/wiki/Abiogenesis=/= > > evolution > > > "In the natural sciences, abiogenesis (pronounced /eɪËbaɪ.ɵËdÊÉnɨsɪs/, > > ay-BYE-oh-JEN-É-siss) or biopoesis is the theory of how life on Earth > > could have arisen from inanimate matter. It should not be confused > > with evolution,. . ." > > Well I'm not sure I'd rely on Wikipedia for a contentious subject like > this, but in any event we needn't talk specifically about how the > basic DNA first developed. The prevailing theory is that it was RNA first, not DNA. Does that help? > If we simply talk of the diversity of life > on Earth, evolution is still unfalsifiable, because it makes no > definite predictions about what you will see. Nor is the diversity of life on earth claimed to be a testable conclusion of evolution. Geez. > Indeed it does not > describe the characteristics of any common ancestor, and nor does it > predict the evolution of any particular animal with any particular > traits. Actually, yes, it does. You need to see some of the studies of finches that have been done.
From: PD on 2 Mar 2010 11:29
On Mar 1, 6:29 pm, Ste <ste_ro...(a)hotmail.com> wrote: > On 1 Mar, 19:26, PD <thedraperfam...(a)gmail.com> wrote: > > > On Mar 1, 7:13 am, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > And I did not call you an idiot. > > > > No, I was gloatingly referring to what others have alleged. > > > At this point, I have to say I'm disappointed. You came here a short > > time ago ostensibly to ask of experts (like any student might) for an > > elaboration or a better explanation of things you did not understand > > about relativity. In the course of the early conversations, you asked > > several insightful question and pressed for clarification, just like > > any fairly decent student would, and I believe I encouraged you on > > that. > > Indeed. You are by far the most reasonable poster I've spoken to here > Paul. Whatever our differences, we are able to conduct a fairly > reasonable discussion. > > > Now it appears that you have been less interested in getting what you > > said you came for than in the sport of verbal jousting. It's a common > > game on newsgroups, where an amateur comes in to see how long he can > > mix it up with the experts, and a "win" is to be had if the amateur > > can catch the expert in the act of making an inaccurate or misleading > > statement. > > It's not that I'm looking to catch out experts. We all make mistakes, > and often (probably too often!) I find it necessary to climb down when > I realise I've shot from the hip. > > > Anybody put in a teaching position is well familiar with the > > experience of telling a student, "You're right, I could have said that > > better," or "Yes, you're right, what I just said is not quite right," > > and then the expert revises his explanation to better and more > > accurately represent what he's trying to explain. It's nothing really > > to gloat over. > > As I say, I was gloating over the fact that I've been subjected to the > forces of hell by the hubristic riff-raff here, who are now > backtracking as it slowly emerges that I know a great deal more than > in their previous estimations, and that they know a great deal less > than in their previous estimations. I'd be careful with the last statement. You certainly have demonstrated that you can think through some things and to look for ambiguities or statements that would point to incorrect conclusions if not refined. That is critical thinking. That is not knowledge. You are to be commended on your critical thinking ability, as it is a good property for a promising student. But until you've learned something, you can't say you know it. |