A constant speed of light in all reference frames? Surely you can't be serious.
in [Relativity]
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From: Inertial on 1 Mar 2010 01:49 "Ste" <ste_rose0(a)hotmail.com> wrote in message news:6d1b660b-6304-48b6-ab7f-5098e403bd5f(a)q23g2000yqd.googlegroups.com... > On 1 Mar, 05:19, "Inertial" <relativ...(a)rest.com> wrote: >> "Ste" <ste_ro...(a)hotmail.com> wrote in message >> >> news:320d036e-35c6-4a2b-ba4b-1d8e3a9067ba(a)z11g2000yqz.googlegroups.com... >> >> >> >> >> >> > On 28 Feb, 07:45, "Peter Webb" <webbfam...(a)DIESPAMDIEoptusnet.com.au> >> > wrote: >> >> I'm confused, because I thought we previously agreed that two >> >> observers travelling along the same axis, maintaining equidistance >> >> from both events at all times, would both report each event as >> >> simultaneous with the other event. And moreover, if they not only both >> >> maintained equidistance from both events, but if they maintained a >> >> separation which was equal for both observers (which, if both >> >> observers are moving relative to each other, requires either a >> >> collision course between observers, or travel in diametrically >> >> opposite directions), then there is no question that the signals are >> >> received simultaneously. >> >> >> Illustration: >> >> >> E1 >> >> >> -------- >> >> >> E2 >> >> >> The line represents the line between events E1 and E2, along which the >> >> observers may move while always reporting both events to be >> >> simultaneous. >> >> >> _________________________________ >> >> You still don't get it. You can say two events appeared to >> >> simultaneous >> >> or >> >> "were" simultaneous in *some* inertial reference frame. That does >> >> *not* >> >> mean >> >> they appeared simultaneous or "were" simultaneous in some *other* >> >> reference >> >> frame. The concept that is lost is "absolute simultaneity", not >> >> "simultaneity within a particular reference frame". >> >> > But clearly if the two *observers* are moving relative to each other, >> > then this is the definitive proof that events can be simultaneous when >> > measured from more than one reference frame. >> >> No .. it isn't. Do you know what an 'event' is? >> >> > And in some >> > circumstances, the simultaneity also aquires an "absolute" character, >> >> Nope >> >> > in that the events would be observed to be simultaneous if the two >> > observers were able to synchronise their clocks by a form of >> > instantaneous communication. >> >> Clocks that are wrong can show any time you want. But differently moving >> observers will always read a different difference in time on a given pair >> of >> separated clocks. > > No they won't Inertial. I suggest you get out a paper and pencil, and > do some working out. OK .. as long as they are separated in the direction of relative motion between any given pair of observers.
From: mpalenik on 1 Mar 2010 02:12 On Mar 1, 12:47 am, "Inertial" <relativ...(a)rest.com> wrote: > "Ste" <ste_ro...(a)hotmail.com> wrote in message > > news:a34363d2-1afe-4b36-9ee8-65fc8ffc825a(a)t23g2000yqt.googlegroups.com... > > > > > > > On 28 Feb, 16:33, Bruce Richmond <bsr3...(a)my-deja.com> wrote: > >> On Feb 28, 1:54 am, Ste <ste_ro...(a)hotmail.com> wrote: > > >> > Illustration: > > >> > E1 > > >> > -------- > > >> > E2 > > >> > The line represents the line between events E1 and E2, along which the > >> > observers may move while always reporting both events to be > >> > simultaneous. > > >> You are correct about E1 and E2 being simultaneous to all observers on > >> the line despite their motion relative to other observers on the > >> line. The statement about spatially seperated events is about > >> seperation along the axis of travel. > > That is correct > > >> In the train experient A and B > >> are on the tracks, which we call the x axis. You have E1 and E2 off > >> to the sides of the tracks on the y axis, which isn't normally > >> considered in the train experiment. > > > This is called "revisionism", Bruce. > > No .. its not > > > The statement was not "about > > seperation along the axis of travel". It was about "what is > > simultaneous in one frame is not simultaneous in another", and "Ste, > > you are an idiot who knows nothing about SR". > > > Apparently, both statements have been falsified. Hehehe. Next! > > There are no two frames where all event simultaneous in one frame are > simultaneous in another. > > Bad luck STE.- Hide quoted text - > > - Show quoted text - I briefly stopped by this thread today, only to find that Ste's mental retardation appears to be growing with time, along with the idiocy of his statements. Ste, if you do take the time to write up some utterly imbicillic response to this message, I won't bother to respond, but I have just a few things for the other posters in this thread. Since the modern scientific method was developed (and yes, Ste a universally agreed upon thing does exist, http://www.sciencebuddies.org/mentoring/project_scientific_method.shtml -- which every scientist here should agree pretty much encompasses it, and which began with the writings of Bacon and Descartes) falsifiability has been a necessary criterion for any scientific theory. The fact that Ste's is just too plain stupid to understand most scientific theories and yet still feels qualified to describe them in detail is what leads him to believe that they are not falsifiable, however here are some ways that his so-called "unfalsifiable theories" can (or could have been falsified). This is mainly for everyone else to use as a starting point, since I'm sure Ste will not be able to understand this correctly, and it will require further explanation if his particularly weak mind is even to grasp a small fraction of the actual implications of the things below. 1) Dark matter -- most of the visible matter in galaxy clusters is actually between the galaxies, in the form of a dilute plasma that gives off x-rays called the intergalactic medium. When galaxy clusters collide, the galaxies usually pass by each other without interacting but the intergalactic medium in the two clusters collides and interacts, which can be seen by looking at x-ray images of the galaxy clusters. By looking at the gravitational lensing of the galaxies behind the clusters, it is possible to figure out how the mass is distributed inside the cluster. We know where most of the visible matter is, because we can see it. We know where most of the actual mass is, because of gravitational lensing. If there were no dark matter, most of the mass that we measure would be located in the intergalactic medium. If dark matter exists, most of the mass would be located inside the galaxies (since dark matter is supposed to form halos around galaxies). (Note, this experiment has been done--look up the bullet cluster). This is an experiment that could falsify the theories of dark matter. Witih dark matter, we predict one thing, and if we observed something else, it would be false. Keep in mind that to be "dark matter" all it has to be is matter that we can't see. There are two main theories of dark matter. One is that it is normal baryonic matter that's just too "dark" to see, although IIRC there is evidence to support that this is not the correct theory. The other theory postulates that dark matter is a form of matter that does not interact electromagnetically at all. 2) Special relativity -- If the measured time dialation on a clock was different than what special relativity predicts, if the speed of light were found to depend on the orientation of the source and detectors, or if the energy and momentum calculated by special relativity (different from Newton's formulae) were not found to be conserved in particle accellerators (it is), that would falsify special relativity. 3) Evolution -- It seems that no one here is in the field of biology and so none of us nearly as well equiped to deal with this question as an evolutionary biologist, or someone in that field. But one thing that Ste seems confused on is the difference between evolution and abiogenesis. Evolution is not actually theory on the origin of life, although most proponents would likely support a naturalistic origin of life. However, evolution is a theory about how diversity occurs AFTER the first self replicating (living) molecules existed. Evolution alone does not explain how those first self replicating molecules came into existence. The field of *biology* does, but not through the theory of evolution, rather through closely related theories of abiogenesis http://en.wikipedia.org/wiki/Abiogenesis Since I'm not an expert on the subject, and it appears no one else is, either, here are a few ways in which evolution could be falsified: Irreducible complexity - if it could be found that there exists a complex structure that has no useful function when modified slightly or reduced to some simpler structure, this would falsify evolution. So far, all structures that proponents of intellegent design have proposed as irreducibly complex can be shown to serve a useful purpose in a simpler form. Genetic similarity between various species - all animals should share similar DNA. Animals that are more closely related should have more similar DNA. The DNA of human ancestors should gradually approach modern human DNA as we go forward in time through the fossil record. If it could be shown that this were not the case, evolution could be shown to be false. Whether or not this can distinguish it from creationism (although the last part CAN) is irrelevant to whether or not the theory can be falsified. 4) Quantum mechanics - If the energy spectrum or bonding energy of an atom can be shown to be different than those predicted by quantum mechanics, quantum mechanics would be falsified. We regularly do these calculations in my group for very complex moleculare systems, to a high degree of accuracy. If the wave function observed by an STM is significantly different from that which is predicted by quantum mechanics, this could falsify quantum mechanics. If simultaneous measurements of non-commuting operators (such as position and momentum) can every be carried out to a higher degree of accuracy than that which is predicted by quantum mechanics, then the theory would be falsified. 4) String theory -- as people have been repeatedly tried to tell you, there *is no working string theory yet*. Scientists are working *TOWARD* a complete string theory. There are currently several candidates for a string theory but their predictions are not falsifiable with any current technology. There is no current, working string theory because there is no way to say which version, if any, is correct. The reason string theorists are scientists is because they are trying to find a way to either use string theory to make testable predictions (such as black hole entropy, which at least some versions of string theory can correctly predict, maybe all--I don't know enough to say for sure), or find a way to create some type of experiment that can distinguish between string theories. Again, there IS NO CURRENT WORKING STRING THEORY, ONLY SEVERAL CANDIDATES. Note also that for a theory to be falsifiable it doesn't mean that the theory is false or that when the test is run it will demonstrate that the theory is false. It only means that the theory makes predictions which can be tested and shown to be true or false and that if any of these predictions is false, the theory is false. Note for a theory to be falsifiable, it also does not mean that no other theory can make the same predictions (although experiments will need to be done to distinguish between the two theories to find out which is more likely to be correct), only that it makes predictions which can falsify it. Falsifiablity is not necessarily a way to distinguish between two theories, only a necessary criterion for any scientific theory.
From: Peter Webb on 1 Mar 2010 02:15 "Ste" <ste_rose0(a)hotmail.com> wrote in message news:9c82c2ff-bbb2-4716-ab1c-14b52523722f(a)o3g2000yqb.googlegroups.com... > On 28 Feb, 07:07, "Peter Webb" <webbfam...(a)DIESPAMDIEoptusnet.com.au> > wrote: >> "Ste" <ste_ro...(a)hotmail.com> wrote in message >> >> On 27 Feb, 15:44, PD <thedraperfam...(a)gmail.com> wrote: > >> > > I think you're attributing an absurd definition to "science". Paul >> > > Draper probably had a more tenable argument when he said that string >> > > theorists are scientists doing science, but that they do not yet have >> > > a "scientific theory". But I know from talking to him that he >> > > attributes a very contorted meaning to the phrase "scientific >> > > theory", >> > > that would condemn a lot of scientific knowledge, both historical and >> > > current, as being "unscientific". >> >> > Examples, please. >> >> In physics I would raise the same old example: string theory . But >> there are certainly more. We have things like "dark matter". Or even >> Newton. Or Galileo. And more broadly, in biology we have evolution, >> and in economics, rational choice theory. >> >> __________________________________ >> All of these things are falsifiable, or they are not scientific theories. >> I >> don't know much about string theory, but the rest are certainly >> falsifiable. >> Newton's theory was in fact falsified by observation. In another part of >> the >> thread, I gave you half a dozen ways evolution could have been falsified. > > Not true. > Direct quote: "Here are some obvious areas in which evolution could be easily falsified: 1. Epidemiology 2. Molecular biology 3. Paleontology 4. Genetic engineering 5. Agricultural science 6. Zoology" I then went on to provide specific observations which would falsify evolution. > > >> All managed to fail your previously stated requirement of a >> "scientific theory", which (amongst other things) is being falsifiable >> (in a practical rather than just notional sense), not ad-hoc, and >> predicting observations that are not already accounted for. >> >> _______________________________ >> I didn't state any of these requirements other than it was falsifiable. > > Well I was replying to Paul. So you have no issue with my statement. Excellent. > > > >> All >> of those theories are, at least as I understand them, with the proviso I >> know zero about string theory and not a lot about some of the others. I >> have >> already demonstrated how many of them in fact could be falsified. > > String theory is *not* falsifiable. OK, if you say so. > Dark matter is resistent to > falsification, because it "does not interact except through gravity > and inertia". That does not stop dark matter being falsified, but does mean that falsification would require us to change our theories on gravity and inertia. > Both Newton and Galileo were falsified a number of times > by their contemporaries, and they were forced to revise (of course, > this was before Popper). Many of Newton's theories were falsified at the time, but not as far as I am aware his theory of gravitation. Have you a link for this, or did you make it up? > We've dealt with evolution elsewhere. > Rational choice theory is either falsified when it makes express > claims as to what people want, or it becomes unfalsifiable when it > makes no express claim as to what people want. I thought we were talking about physics? Cranks and changing the subject ....
From: mpalenik on 1 Mar 2010 02:21 On Mar 1, 2:15 am, "Peter Webb" <webbfam...(a)DIESPAMDIEoptusnet.com.au> wrote: > "Ste" <ste_ro...(a)hotmail.com> wrote in message > > Dark matter is resistent to > > falsification, because it "does not interact except through gravity > > and inertia". > > That does not stop dark matter being falsified, but does mean that > falsification would require us to change our theories on gravity and > inertia. Just wanted to point out, things don't interact through "inertia". Dark matter, under the WIMP theory, interacts only under gravity and the weak force.
From: Peter Webb on 1 Mar 2010 02:24
"Ste" <ste_rose0(a)hotmail.com> wrote in message news:320d036e-35c6-4a2b-ba4b-1d8e3a9067ba(a)z11g2000yqz.googlegroups.com... On 28 Feb, 07:45, "Peter Webb" <webbfam...(a)DIESPAMDIEoptusnet.com.au> wrote: > I'm confused, because I thought we previously agreed that two > observers travelling along the same axis, maintaining equidistance > from both events at all times, would both report each event as > simultaneous with the other event. And moreover, if they not only both > maintained equidistance from both events, but if they maintained a > separation which was equal for both observers (which, if both > observers are moving relative to each other, requires either a > collision course between observers, or travel in diametrically > opposite directions), then there is no question that the signals are > received simultaneously. > > Illustration: > > E1 > > -------- > > E2 > > The line represents the line between events E1 and E2, along which the > observers may move while always reporting both events to be > simultaneous. > > _________________________________ > You still don't get it. You can say two events appeared to simultaneous or > "were" simultaneous in *some* inertial reference frame. That does *not* > mean > they appeared simultaneous or "were" simultaneous in some *other* > reference > frame. The concept that is lost is "absolute simultaneity", not > "simultaneity within a particular reference frame". But clearly if the two *observers* are moving relative to each other, then this is the definitive proof that events can be simultaneous when measured from more than one reference frame. ____________________________________ Can appear simultaneous, yes, of course. That is a standard part of SR. And in some circumstances, the simultaneity also aquires an "absolute" character, in that the events would be observed to be simultaneous if the two observers were able to synchronise their clocks by a form of instantaneous communication. ________________________________ "if the two observers were able to synchronise their clocks by a form of instantaneous communication.", or if pigs could fly, or Star Trek instantaneous teleporters existed, or I was the President of China. Show me how they can synchronise their clocks through instantaneous communication and you have an argument. |