Known physics defeated by simple puzzle?
in [Relativity]
|
From: Inertial on 11 Apr 2010 08:09 "Sue..." <suzysewnshow(a)yahoo.com.au> wrote in message news:1d716e5d-6fb0-4a04-9aea-fe249242e945(a)b33g2000yqc.googlegroups.com... > On Apr 10, 6:20 am, "Inertial" <relativ...(a)rest.com> wrote: >> "Ste" <ste_ro...(a)hotmail.com> wrote in message >> >> news:66fad22e-0a13-4979-b17f-2f405eb13607(a)11g2000yqr.googlegroups.com... >> >> >> >> > On 10 Apr, 08:59, "Inertial" <relativ...(a)rest.com> wrote: >> >> "Ste" <ste_ro...(a)hotmail.com> wrote in message >> >> >>news:8431a5cd-222a-4118-9d15-7bcdf6450410(a)c36g2000yqm.googlegroups.com... >> >> >> > On 10 Apr, 07:38, "Inertial" <relativ...(a)rest.com> wrote: >> >> >> "Ste" <ste_ro...(a)hotmail.com> wrote in message >> >> >> >> > The point is simply to talk in qualitative >> >> >> > terms about what happens to "simultaneity" between the points at >> >> >> > the >> >> >> > start and at the end at which we agree that the clocks are >> >> >> > synchronised. >> >> >> >> It changes >> >> >> > Will you quantify this change? >> >> >> I thought you just wanted to talk in qualitative terms. >> >> > I did, but not at such a ridiculously broad level. >> >> >> You also say you >> >> don't want to see math, so I'm not sure what you are expecting here >> >> > Just for you to say, for example, "when the local clock accelerates, >> > the distant clock falls out of simultaneity and leaps ahead... etc." >> > or something of that kind. >> >> I already said all that >> >> >> >> >> >> A frame moving relative to a clock will measure the clock as >> >> >> ticking >> >> >> slower. >> >> >> Less elapsed time will show between an pair of events for the >> >> >> relatively >> >> >> moving clock than an at-rest clock. That is independent of the >> >> >> direction >> >> >> of >> >> >> the relative motion. >> >> >> >> I had though we agreed to ignore illusions due to propagation >> >> >> delays. >> >> >> > Indeed, but when you started talking of the clocks "speeding up", >> >> > that >> >> > caused me confusion. >> >> >> Why? Just do not worry about optical illusions and concentrate on >> >> what >> >> is >> >> actually going on. >> >> > But you said the speeding up bit *is* a result of an optical illusion. >> >> No .. I didn't. If you are talking about what is actually seen, then >> optical illusion makes a difference. But there is NO optical illusion in >> the SR effects on measured clock rates and lengths etc >> >> > You see how hard it is to get a straight but comprehensive answer >> > here? >> >> You get them .. you just don't accept or understand them >> >> >> > would leave a small remainder of slowing, >> >> >> There would be the slowing SR predits. You are talking about >> >> additonal >> >> optical illusions. >> >> > No, >> >> Yes .. you were. > > ================= > >> >> > I was talking about the slowing predicted by SR, which is not >> > accounted for by the effects that we've both already agreed are >> > "illusions". >> >> And that is the 'slowing' SR predicts that is not illusion. The same >> that i >> already described in detail before > > In view of Noether's work with GR and the > *process* we agreed was valid for marking time > You seem to be suggesting an aeroplane > might fly relative to another aeroplane on > some course that would weaken an air marshal's > bullet. That would violate PoR. Why do you think I would be suggesting any such thing? > The statement also also seems inconsistent with > Einstein's formal statement. > http://www.bartleby.com/173/17.html What statement? > I know the practice is frowned on in many schools > but may I suggest you study material before > teaching it. :-) I have
From: Inertial on 11 Apr 2010 08:11 "Ste" <ste_rose0(a)hotmail.com> wrote in message news:996ae2ac-6e26-46b4-9e71-21242c60c54c(a)30g2000yqi.googlegroups.com... > On 10 Apr, 13:05, "Inertial" <relativ...(a)rest.com> wrote: >> "Ste" <ste_ro...(a)hotmail.com> wrote in message >> >> news:db82a4dc-e7c6-4fea-a210-145c805688ef(a)z11g2000yqz.googlegroups.com... >> >> >> >> >> >> > On 10 Apr, 12:24, "Inertial" <relativ...(a)rest.com> wrote: >> >> "Ste" <ste_ro...(a)hotmail.com> wrote in message >> >> >>news:25a765b8-2e31-476f-9935-34014a09438f(a)y17g2000yqd.googlegroups.com... >> >> >> > On 10 Apr, 11:20, "Inertial" <relativ...(a)rest.com> wrote: >> >> >> "Ste" <ste_ro...(a)hotmail.com> wrote in message >> >> >> >> >> > based on >> >> >> >> > the relative speed between the clocks? (and not based on the >> >> >> >> > direction >> >> >> >> > of relative movement?) >> >> >> >> >> Yes. I've already said that. >> >> >> >> > So what is the extent of the slowing, and on what variables does >> >> >> > it >> >> >> > depend? (We can speak in quantitative terms on this point.) >> >> >> >> It depends on the speed. The greater the speed, the larger the >> >> >> effect >> >> >> (see >> >> >> the gamma factor). That affects the measured clock ticking rate >> >> >> and >> >> >> the >> >> >> measure length of a moving object. There is also the effect on >> >> >> simultaneity. >> >> >> >> Its all given by the Lorentz transforms. >> >> >> > Indeed. So there is always a slowing, related to speed, no matter >> >> > what >> >> > relative direction the object may be travelling in. >> >> >> Yes >> >> >> > In other words, if >> >> > an object is approaching you at .9c, it displays a slowing that is >> >> > the >> >> > same as if it were receding at .9c? >> >> >> Yes >> >> >> If by 'displays' you are not including any optical/visual/etc >> >> illusions >> >> due >> >> to propagation delays etc. >> >> > Yes, I had assumed we'd accounted for those already, and are >> > disregarding those effects. >> >> >> And if by 'slowing' you mean that observers at rest in your frame of >> >> reference would measure its ticking rate as slower. >> >> > 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) Why? > 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? Of course, they will be moving, so they won't stay negligibly distant.
From: Sue... on 11 Apr 2010 22:56 On Apr 11, 8:09 am, "Inertial" <relativ...(a)rest.com> wrote: > "Sue..." <suzysewns...(a)yahoo.com.au> wrote in message > > news:1d716e5d-6fb0-4a04-9aea-fe249242e945(a)b33g2000yqc.googlegroups.com... > > > > > On Apr 10, 6:20 am, "Inertial" <relativ...(a)rest.com> wrote: > >> "Ste" <ste_ro...(a)hotmail.com> wrote in message > > >>news:66fad22e-0a13-4979-b17f-2f405eb13607(a)11g2000yqr.googlegroups.com.... > > >> > On 10 Apr, 08:59, "Inertial" <relativ...(a)rest.com> wrote: > >> >> "Ste" <ste_ro...(a)hotmail.com> wrote in message > > >> >>news:8431a5cd-222a-4118-9d15-7bcdf6450410(a)c36g2000yqm.googlegroups.com... > > >> >> > On 10 Apr, 07:38, "Inertial" <relativ...(a)rest.com> wrote: > >> >> >> "Ste" <ste_ro...(a)hotmail.com> wrote in message > > >> >> >> > The point is simply to talk in qualitative > >> >> >> > terms about what happens to "simultaneity" between the points at > >> >> >> > the > >> >> >> > start and at the end at which we agree that the clocks are > >> >> >> > synchronised. > > >> >> >> It changes > > >> >> > Will you quantify this change? > > >> >> I thought you just wanted to talk in qualitative terms. > > >> > I did, but not at such a ridiculously broad level. > > >> >> You also say you > >> >> don't want to see math, so I'm not sure what you are expecting here > > >> > Just for you to say, for example, "when the local clock accelerates, > >> > the distant clock falls out of simultaneity and leaps ahead... etc." > >> > or something of that kind. > > >> I already said all that > > >> >> >> A frame moving relative to a clock will measure the clock as > >> >> >> ticking > >> >> >> slower. > >> >> >> Less elapsed time will show between an pair of events for the > >> >> >> relatively > >> >> >> moving clock than an at-rest clock. That is independent of the > >> >> >> direction > >> >> >> of > >> >> >> the relative motion. > > >> >> >> I had though we agreed to ignore illusions due to propagation > >> >> >> delays. > > >> >> > Indeed, but when you started talking of the clocks "speeding up", > >> >> > that > >> >> > caused me confusion. > > >> >> Why? Just do not worry about optical illusions and concentrate on > >> >> what > >> >> is > >> >> actually going on. > > >> > But you said the speeding up bit *is* a result of an optical illusion. > > >> No .. I didn't. If you are talking about what is actually seen, then > >> optical illusion makes a difference. But there is NO optical illusion in > >> the SR effects on measured clock rates and lengths etc > > >> > You see how hard it is to get a straight but comprehensive answer > >> > here? > > >> You get them .. you just don't accept or understand them > > >> >> > would leave a small remainder of slowing, > > >> >> There would be the slowing SR predits. You are talking about > >> >> additonal > >> >> optical illusions. > > >> > No, > > >> Yes .. you were. > ================= > > >> > I was talking about the slowing predicted by SR, which is not > >> > accounted for by the effects that we've both already agreed are > >> > "illusions". > > >> And that is the 'slowing' SR predicts that is not illusion. The same > >> that i > >> already described in detail before > > > In view of Noether's work with GR and the > > *process* we agreed was valid for marking time > > You seem to be suggesting an aeroplane > > might fly relative to another aeroplane on > > some course that would weaken an air marshal's > > bullet. That would violate PoR. > > Why do you think I would be suggesting any such thing? It seems fair to lump the effects of a light path that is changing length under the term "illusion" but you say there is some other effect that causes a clock to slow. Just to be clear to what you are referring we need to be more specific about the *process* that marks time. Lets say there is a AC dynamo somewhere and both stella and terra's clocks are synchronous motors connected with long wires to that dynamo. Every revolution of the dynamo produces a revolution of both clocks motors. What part of the voyage and by what *process* do the clocks get out of sync? > > > The statement also also seems inconsistent with > > Einstein's formal statement. http://www.bartleby.com/173/17.html > > What statement? << the four-dimensional space-time continuum of the theory of relativity, in its most essential formal properties, shows a pronounced relationship to the three-dimensional continuum of Euclidean geometrical space. In order to give due prominence to this relationship, however, we must replace the usual time co-ordinate t by an imaginary magnitude sqrt(-1) ct proportional to it. Under these conditions, the natural laws satisfying the demands of the (special) theory of relativity assume mathematical forms, in which the time co-ordinate plays exactly the same rôle as the three space co-ordinates. >> http://www.bartleby.com/173/17.html > > > I know the practice is frowned on in many schools > > but may I suggest you study material before > > teaching it. :-) > > I have Fine for the links you snipped. Now you will need this one and a bit of history too. http://farside.ph.utexas.edu/teaching/em/lectures/node50.html Sue...
From: Ste on 11 Apr 2010 23:14 On 11 Apr, 13:11, "Inertial" <relativ...(a)rest.com> wrote: > "Ste" <ste_ro...(a)hotmail.com> wrote in message > > news:996ae2ac-6e26-46b4-9e71-21242c60c54c(a)30g2000yqi.googlegroups.com... > > > > > > > On 10 Apr, 13:05, "Inertial" <relativ...(a)rest.com> wrote: > >> "Ste" <ste_ro...(a)hotmail.com> wrote in message > > >>news:db82a4dc-e7c6-4fea-a210-145c805688ef(a)z11g2000yqz.googlegroups.com.... > > >> > On 10 Apr, 12:24, "Inertial" <relativ...(a)rest.com> wrote: > >> >> "Ste" <ste_ro...(a)hotmail.com> wrote in message > > >> >>news:25a765b8-2e31-476f-9935-34014a09438f(a)y17g2000yqd.googlegroups.com... > > >> >> > On 10 Apr, 11:20, "Inertial" <relativ...(a)rest.com> wrote: > >> >> >> "Ste" <ste_ro...(a)hotmail.com> wrote in message > > >> >> >> >> > based on > >> >> >> >> > the relative speed between the clocks? (and not based on the > >> >> >> >> > direction > >> >> >> >> > of relative movement?) > > >> >> >> >> Yes. I've already said that. > > >> >> >> > So what is the extent of the slowing, and on what variables does > >> >> >> > it > >> >> >> > depend? (We can speak in quantitative terms on this point.) > > >> >> >> It depends on the speed. The greater the speed, the larger the > >> >> >> effect > >> >> >> (see > >> >> >> the gamma factor). That affects the measured clock ticking rate > >> >> >> and > >> >> >> the > >> >> >> measure length of a moving object. There is also the effect on > >> >> >> simultaneity. > > >> >> >> Its all given by the Lorentz transforms. > > >> >> > Indeed. So there is always a slowing, related to speed, no matter > >> >> > what > >> >> > relative direction the object may be travelling in. > > >> >> Yes > > >> >> > In other words, if > >> >> > an object is approaching you at .9c, it displays a slowing that is > >> >> > the > >> >> > same as if it were receding at .9c? > > >> >> Yes > > >> >> If by 'displays' you are not including any optical/visual/etc > >> >> illusions > >> >> due > >> >> to propagation delays etc. > > >> > Yes, I had assumed we'd accounted for those already, and are > >> > disregarding those effects. > > >> >> And if by 'slowing' you mean that observers at rest in your frame of > >> >> reference would measure its ticking rate as slower. > > >> > 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) > > Why? Because this is an area where I am unsure of the answer. > > 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? > > Of course, they will be moving, so they won't stay negligibly distant. Agreed, but the point is that even when they *are* negligibly distant, there will still be this fixed amount of lag based on relative velocity, yes? In other words, velocity relative to the coordinate system is the sole variable? And it's not relative distance (in the same way it is for propagation delays), nor the relative speed of approach or recession (in the same way that it is for Doppler shifting)? And they both argue that it is the *other* who is lagging? (And I know this may sound repetitive, but I'm just making absolutely sure there is an understanding here.)
From: Ste on 11 Apr 2010 23:43
On 11 Apr, 19:02, PD <thedraperfam...(a)gmail.com> wrote: > On Apr 10, 11:55 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > 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. > > I disagree that "everyone else" uses these, and I find it astonishing > that you would presume to speak for, let alone think like, "everyone > else". What I am saying is that everyone uses "arbitrary and capricious labels", as you put it. > > 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, > > ...such as temporally ordered cause and effect between strictly > material agents... Despite your snipe Paul, there is actually some evidence for this, and as you've conceded before, no experimental evidence against it. Even when I questioned you on the issue of premonition and cause, you found it very difficult to explain how it could be experimentally distinguished from cause and effect. Incidentally, I recall that our definition of "material" is different - remember, my defintion includes what you call the "immaterial". > > 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. > > In other words, they are ignorant, uneducated, and cowing to > authority. Generally they are ignorant and uneducated, but more to the point they accept something as true *simply* because authority says it is true, and same is true for the authority in turn. > > 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, > > ...such as temporally ordered causality between strictly material > agents... Yes. I said at the outset of my previous post that there is an ideological (although in this context, for clarity, I prefer to say an "axiomatic"-) component to my beliefs - which defines the sort of explanations I'm willing to accept, what sort of evidence I'm willing to accept, etc. And before you claim that science, or scientists, don't have ideology, I refer you back to what I said many months ago, that an ignorance of ideology, or a lack of concern with it, is not the same as an absence of ideology. |