Known physics defeated by simple puzzle?
in [Relativity]
|
From: NoEinstein on 11 Apr 2010 00:31 On Apr 8, 10:09 pm, Ste <ste_ro...(a)hotmail.com> wrote: > On 8 Apr, 15:10, PD <thedraperfam...(a)gmail.com> wrote: > > > On Apr 7, 10:32 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > It's awfully difficult to misinterpret the numerical value of a > > measurement and whether it agrees with the numerical value of another > > measurement. > > No, because if I say relative to me A is moving at 10kmh and B is > moving at 20kmh, and you say that relative to you A is moving at > 20kmh, and B moving at 30kmh, then despite the numerical difference of > speeds we both agree about the movement of A relative to B. Dear Ste: Save your effort. Explaining anything requiring more than a 1 neuron brain to PD is an exercise in futility! NE
From: NoEinstein on 11 Apr 2010 00:47 On Apr 9, 8:30 pm, "Sue..." <suzysewns...(a)yahoo.com.au> wrote: > On Apr 9, 8:04 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > > On 10 Apr, 00:46, "Inertial" <relativ...(a)rest.com> wrote: > > > > "Ste" <ste_ro...(a)hotmail.com> wrote in message > > > >news:b55913f6-a3d0-401c-878b-4d0ec3677fa3(a)11g2000yqr.googlegroups.com.... > > > > > On 9 Apr, 22:24, PD <thedraperfam...(a)gmail.com> wrote: > > > >> On Apr 9, 3:31 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > >> > > But that is not what happens. > > > >> > > For example, if I see a car traveling west at 10 kmh, and a car > > > >> > > traveling east at 35 kmh, then you have the expectation that, to a > > > >> > > passenger riding in the car traveling east, the other car is > > > >> > > traveling > > > >> > > 45 kmh west. > > > >> > > But in fact, it is not traveling at 45 kmh west to a passenger in > > > >> > > that > > > >> > > car. > > > >> > > It is traveling at something close to that, but only approximately. > > > > >> > > The bottom line is, the basic sum rule you've been taught for > > > >> > > relative > > > >> > > velocities is a LIE. > > > > >> > i would expect the combined speed to be a real 45kmh, yes, although > > > >> > it's quite possible that none of them will any longer agree on the > > > >> > definition of "hour" or "kilometer". > > > > >> Oh, no, they agree on the definition of hour and kilometer, alright. > > > >> Something that is measured locally to be a km will still be measured > > > >> locally to be a km. And a standard process that locally takes an hr > > > >> will still locally take an hour. > > > > > Indeed, the question is whether their respective measures of "an hour" > > > > are truly identical. > > > > What do you mean by 'truly identical' > > > In other words, whether they are measuring the same periods of time - > > whether the interval of each tick of each clock would be the same as > > each other. > > The coordinate time of SR is derived > from light signal exchange. E-sync. > > Real clock mechanisms don't "measure" time > they mark it. Tape a metre stick to gun > barrel. The graduations on the metre stick > become units of time. joule /==> gram > > *K.E. = 1/2 mv^2 > > http://en.wikipedia.org/wiki/Noether%27s_theorem#Applications > > Sue...- Hide quoted text - > > - Show quoted text - Dear Sue: *That "KE" formula violates the Law of the Conservation of Energy. My modified momentum formula replaces it: KE = a/g (m) + v / 32.174 (m). NoEinstein
From: Ste on 11 Apr 2010 00:55 On 10 Apr, 18:24, PD <thedraperfam...(a)gmail.com> wrote: > On Apr 9, 6:52 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > There is always > > > this loose, hand-waving out: "Maybe we only *think* there are laws of > > > physics, but there aren't laws at all and we're just given the > > > appearance that there are," or "I choose to believe that the laws that > > > you've deduced are all wrong, and that there are some other laws that > > > are at work instead. I haven't got the foggiest idea what they are, > > > but they surely will be easier for me to accept than the ones you've > > > found so far." > > > Indeed. If the odds of history are anything to go by, it is always > > best to bet against the truth of any current scientific theory. > > Thanks, this tells me just about everything I need to know. And what does it tell you? > > > In which case, there is no distinction WHATSOEVER in your mind between > > > science and religion, or for that matter any belief system including > > > morals, customs, common opinions, fads and fancies. That is because > > > there is no such thing as "naturalistic ideology" other than a > > > completely subjective and capricious assignment on an item by item > > > basis: "This is natural. This, too, is natural. This, however, is not, > > > and neither is that over there." And in fact, you can make no > > > distinction whatsoever between the study of the natural universe and > > > head-scratching over whether a round belly on a woman is to be > > > considered beautiful. Since you can make no defensible distinction > > > between these two, or in fact, any two contentions of any variety > > > whatsoever, I'm curious why you have an interest in science, other > > > than as another example of mental diddling. > > > I'm interested in science because I'm interested in the natural world, > > Which "natural world" is only demarcated by your arbitrary and > capricious labels. Which is the same arbitrary and capricious labels that everyone else uses. As I've said, the only difference is that a minority continue to insist that somehow science has no ideological content at all. For me, there is no useful argument to be had on, for example, whether unicorns or angels are "natural" or not - the real question is what sort of ideological framework do they fall into, and invariably you find that a belief in unicorns and angels is simply ancilliary to an ideology involving the supernatural, or ancilliary to a belief that the world does not operate in an understandable, predictable, and mechanistic way (which really sums up my axioms, my "ideology" in this respect). In fact, the existence of unicorns would not be incompatible with my general outlook at all. Even angels would not be, as long as they existed within naturalistic principles of cause and effect, and some plausible mechanism was posited for firstly how their influence manifests and secondly for why they have any interaction at all with humanity (or any concern for humanity). But once you scratch the surface, you often find that the explanations to these questions are sorely lacking, and that there is in fact not a great deal of concern with how it may be explained on the part of those who posit the existence of unicorns and angels. Indeed, when you ask where the idea even came from in the first place, the answer is rarely (if ever!) "from personal hypothesis", "from inference", or "from observation", but "from religious authority". Such proponents also tend to have a general worldview that is informed entirely by their imaginations or naive beliefs, and show a total unfamiliarity with history, science, politics, psychology, economics, or any systematic body of human knowledge that might offer any counter to the mere spoken word of their priest or other religious figures, or which may put a different slant on their beliefs. Indeed, for me, I also take the view that it will often be futile to attack ideology using mere logic. Most people hold an ideology because in some way or another because it has a concrete function for them, never because it is wholly logical. The answer to a stubborn ideologue is not to try and convince him otherwise, but instead to rob him of the support of others who can be convinced otherwise (if indeed you can rob him of his support and offer people a better ideology that is more functional for them). As long as people are familiar with the conflicting ideologies of science and religion, then it is fairly certain that most people will continue to support science as long as science continues to deliver the goods. For science to become overly concerned with an appearance of objectivity, or to try too hard to repress religion, will in fact be damaging for science - and may in fact be a reflection of the fact that science is delivering certain answers that scientists, and their paymasters, don't want to hear (because it conflicts with the tenents of the prevailing political ideology, in which the scientists often have a personal vested interest).
From: Ste on 11 Apr 2010 01:02 On 11 Apr, 05:12, "Peter Webb" <webbfam...(a)DIESPAMDIEoptusnet.com.au> wrote: > "Ste" <ste_ro...(a)hotmail.com> wrote in message > > > > Ah, I've just realised another question. I was assuming that we're > > > talking about a fixed amount of "lag" in distant clock. Is that what > > > you're talking about, or are you talking about an *ongoing* loss of > > > time? In other words, the longer the distant clock is moving, the more > > > its time lags behind that of the local clock (and, yet, all this lag > > > is recouped when the two clocks return to relative rest). > > > The 'lag', as you call it, is distance and velocity dependent. When there > > is no distance between them and no difference in motion, there is no > > 'lag'. > > Yes, but the important thing (for me) to clarify is that, even if > there is only a negligible distance between them, if there is a > relativistic difference in velocity, then there will still be a fixed > amount of time lag? > > ________________________________ > SR does not impose a fixed "time lag". It says that clocks in different > inertial frames run at different "rates". This has nothing to do with the > relative position, only the relative speed. > > In the twins paradox, the difference in ages when the twin returns could be > considered the "lag". If the travelling twin travels twice as far and > returns, then the difference in ages (the lag) will be twice as much when he > returns. But you're back to talking about the twins paradox. Please will you actually stick to talking about the specific scenarios that I've specified. In my scenario, we've already agreed that at the start, and at the end, the clocks are pefectly synchronised - there is no "difference in ages" in my scenario.
From: Timo Nieminen on 11 Apr 2010 01:45
On Apr 11, 5:35 am, Edward Green <spamspamsp...(a)netzero.com> wrote: > On Apr 6, 7:30 pm, Timo Nieminen <t...(a)physics.uq.edu.au> wrote: > > > 3. Can the observer see the Lorentz contraction of the pole? > > Not cleanly. What the observer will see will be the "optical illusion" length, which includes the effect of Lorentz contraction. A full answer to this part would mean finding out whether or not the Lorentz contraction is a visibly significant part of the total effect. Some guess as to visual acuity might be needed. For even more fun, you can figure out what something - or two things, such as the two ends of a rod - looks like in arbitrary motion. Not just including acceleration, but also superluminal motion if you like (which could be easily achieved by shining one or two spots of light onto a giant screen, and then sweeping them around). Anyway, after that little bit of reinforcement, why not check out Real Time Relativity, http://realtimerelativity.org/ , and see this in action! |