A constant speed of light in all reference frames? Surely you can't be serious.
in [Relativity]
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From: mpalenik on 15 Feb 2010 22:28 On Feb 15, 7:32 pm, Ste <ste_ro...(a)hotmail.com> wrote: > On 15 Feb, 19:54, mpalenik <markpale...(a)gmail.com> wrote: > > > On Feb 15, 1:40 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > Velocity is rotation, just rotation in a way that you're not used to > > > > being able to rotate. There's nothing else to explain. You > > > > accellerate something, it rotates. That's a physical answer. > > > > But you could give a simple demonstration of spatial rotation. Indeed, > > > people knew how to rotate things in space long before formal geometry > > > was ever developed. > > > I can give you a simple example of the rotation I've just described. > > Accellerate an object. That's a rotation. The only reason people do > > not recognize it as such is because we can't step back and see the > > geometry of the 4 dimensional universe. > > As I said, the real world existed long before geometry. You seem to insist that 4 dimensional spacetime is some abstract philosophical thing when really, it's nothing of the sort. The real world exists as a 4 dimensional manifold. That's not dependent on mathematical tricks. You have a four dimensional space. We call one of those dimensions time. You percieve a 3 dimensional world. But you have to realize that's only your perception and that the universe exists outside of your perception. > > > However, to an observer who sits in a 3D cross section of spacetime, > > this is exactly how rotations would appear. > > > It's like you're living in flat land, but flatland is sitting on a > > platform moving upward (representing your "motion" through time). A > > rotation out of the plane in flat land might not look exactly like a > > normal rotation that the flatlanders are used to, but mathematically, > > it would still be recognizable. > > Mark, this is just meaningless. You're just thinking of a way to > describe the same *mathematical* concepts in concrete terms, which > actually detracts from the coherence and credibility of the > explanation. No, what I wrote is meaningful. What you wrote is meaningless. > > > It's the same with SR. The fault is your perceptions, not the > > explanation. > > No the fault is that you don't (or most probably can't) tailor your > explanation to the audience. I dare say the next time someone asks for > a "physical explanation", you'd do better to just say "I don't > understand relativity in those terms", and then everyone knows where > they stand. I understand relativity in the actual terms of the way the universe really works. You're looking for something that conforms to your specific desires, which relativity does not. Let's try it this way: what about the picture I drew for you do you not think could represent physical reality? > That's not at all to devalue the skills that you do have, > but it is to recognise that you either lack the capability or the > inclination to explain your understanding in terms that this > particular audience can understand, and you would do well to recognise > this as a deficit, rather than chalking it up to the "preconceptions" > of others. > > > > But "rotation into time" is totally meaningless in the sense that it's > > > supposed to have any analogy with spatial rotation. It's a bit like > > > "light follows a groove in space" - the supposed concrete analogy > > > actually introduces more confusion. > > > It's not just an analogy, it's a physical reality. Look at the > > picture I drew you. It means exactly what that picture shows (except > > in Minkowski spacetime, rather than euclidean). > > It *represents* something in the real world. It is not physical > reality itself. At least, it isn't for people like me. It represents rotation, just like when I tell you that I rotated a pole, that also represents a rotation. You just don't understand that the two things are the same. You insist that they must be different but in reality, they are not. They don't look quite the same to you because of your perspective. It's exactly like the flatland example I gave before. If you have people that live on a little, flat world sitting in our 3 dimensional space, who can only percieve the things that exist inside of their little 2 dimensional world, when something rotates into that third dimension, they'll go "what the heck just happened? That doesn't look like any rotation I've ever seen." > > The picture I made for you wasn't supposed to represent an analogy--it > > was supposed to represent physical reality (except with a slightly > > different metric--but we don't need to worry about that just yet). > > If you don't recognise geometry as being an abstract *representation* > of the physical world, as opposed to the physical world itself, then > that is a clear difference in our understandings - and it's a > philosophical difference which will not be reconcilable. It's no more or less geometry that showing you a picture of a pole that's rotated in our regular 3 dimensional space. It's no more abstract than that. Why do you insist on calling it something more abstract than that? The picture I showed you is exactly the same thing. Relable the axes x and y, instead of x and t. Now can you agree that it's simply a picture of a rotated pole? Now, suddenly if I switch the axes back to x and t, does it magically become more abstract just because I changed the labels?
From: mpalenik on 15 Feb 2010 22:28 On Feb 15, 10:01 pm, kenseto <kens...(a)erinet.com> wrote: > On Feb 15, 5:48 pm, mpalenik <markpale...(a)gmail.com> wrote: > > > > > On Feb 15, 3:38 pm, kenseto <kens...(a)erinet.com> wrote: > > > > On Feb 15, 12:27 pm, mpalenik <markpale...(a)gmail.com> wrote: > > > > > On Feb 15, 6:54 am, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > On 14 Feb, 23:46, mpalenik <markpale...(a)gmail.com> wrote: > > > > > > > On Feb 14, 2:03 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > > > I'm afraid you're easily satisifed Tom. As I say, I'm not really > > > > > > > interested in learning geometry, or talking about completely > > > > > > > hypothetical "grooves in spacetime". > > > > > > > And as many people have repeatedly tried to explain to you, the answer > > > > > > simply is geometry. When you accellerate, you rotate in spacetime. > > > > > > Why? Because that's what accelleration means. That's what it means > > > > > > to be travelling with a certain velocity with respect to something > > > > > > else. It means that you're both "facing different directions". Every > > > > > > effect predicted by relativity can be explained simply by the fact > > > > > > that two different observers at different speeds are "facing different > > > > > > directions" in spacetime--because that's what it means to be moving > > > > > > with respect to something else. It means that you have a different t > > > > > > and x axis. > > > > > > Mark, if you consider this an answer, then you simply haven't > > > > > understood the question.- Hide quoted text - > > > > > > - Show quoted text - > > > > > And if you think there's more to it than that, then you haven't > > > > understood the answer. The above explains everything about relativity > > > > and there's no ambiguity when you understand it. > > > > > Going back to the fitting a ladder into a barn analogy, it's like you > > > > have a ladder to long to fit into the barn, you turn it at an angle, > > > > and it fits, and then someone starts asking you what "physically" > > > > happened to the ladder. You say "well, it got rotated, so it's > > > > shorter in the horizontal direction". Then the person keeps demanding > > > > a physical explanation, and you say you just rotated the ladder, so it > > > > takes up a bit more space in the vertical and less in the horizontal > > > > but the total length of the ladder didn't change. > > > > In this case you are not fitting the length of the ladder through a > > > narrow door way. You are fitting a skinny side of the ladder through a > > > wider door way. > > > This is not the same as an 80 ft long material pole can fit into a 40 > > > ft long material barn with both doors close simultaneously. In this > > > case material contraction must occur. That's thee reason why modern > > > interpretation of length contraction in Sr is merely a geometric > > > effect instead of material or physical effect as asserted by the > > > runts of the SRians such as PD and you. > > > > Ken Seto > > > Wow, SRian. . . that's a word that nobody in the real world uses. > > LOL--it's funny reading this group just for the ridiculous lingo the > > crackpots make up in an attempt to be insulting. > > Exactly...it is used to decribe crackpots like you and PD. > > Ken Seto > Priceless.
From: Inertial on 15 Feb 2010 22:32 "kenseto" <kenseto(a)erinet.com> wrote in message news:65fb4cc2-4dcb-4a03-a564-a5787f7e3550(a)w31g2000yqk.googlegroups.com... > On Feb 15, 5:16 pm, "Inertial" <relativ...(a)rest.com> wrote: >> "kenseto" <kens...(a)erinet.com> wrote in message >> >> news:65b0b432-ea12-4f62-8dea-14b916d28a20(a)15g2000yqi.googlegroups.com... >> >> >> >> >> >> > On Feb 15, 4:06 pm, PD <thedraperfam...(a)gmail.com> wrote: >> >> On Feb 15, 2:38 pm, kenseto <kens...(a)erinet.com> wrote: >> >> >> > On Feb 15, 12:27 pm, mpalenik <markpale...(a)gmail.com> wrote: >> >> >> > > On Feb 15, 6:54 am, Ste <ste_ro...(a)hotmail.com> wrote: >> >> >> > > > On 14 Feb, 23:46, mpalenik <markpale...(a)gmail.com> wrote: >> >> >> > > > > On Feb 14, 2:03 pm, Ste <ste_ro...(a)hotmail.com> wrote: >> >> >> > > > > > I'm afraid you're easily satisifed Tom. As I say, I'm not >> >> > > > > > really >> >> > > > > > interested in learning geometry, or talking about completely >> >> > > > > > hypothetical "grooves in spacetime". >> >> >> > > > > And as many people have repeatedly tried to explain to you, >> >> > > > > the >> >> > > > > answer >> >> > > > > simply is geometry. When you accellerate, you rotate in >> >> > > > > spacetime. >> >> > > > > Why? Because that's what accelleration means. That's what it >> >> > > > > means >> >> > > > > to be travelling with a certain velocity with respect to >> >> > > > > something >> >> > > > > else. It means that you're both "facing different >> >> > > > > directions". >> >> > > > > Every >> >> > > > > effect predicted by relativity can be explained simply by the >> >> > > > > fact >> >> > > > > that two different observers at different speeds are "facing >> >> > > > > different >> >> > > > > directions" in spacetime--because that's what it means to be >> >> > > > > moving >> >> > > > > with respect to something else. It means that you have a >> >> > > > > different t >> >> > > > > and x axis. >> >> >> > > > Mark, if you consider this an answer, then you simply haven't >> >> > > > understood the question.- Hide quoted text - >> >> >> > > > - Show quoted text - >> >> >> > > And if you think there's more to it than that, then you haven't >> >> > > understood the answer. The above explains everything about >> >> > > relativity >> >> > > and there's no ambiguity when you understand it. >> >> >> > > Going back to the fitting a ladder into a barn analogy, it's like >> >> > > you >> >> > > have a ladder to long to fit into the barn, you turn it at an >> >> > > angle, >> >> > > and it fits, and then someone starts asking you what "physically" >> >> > > happened to the ladder. You say "well, it got rotated, so it's >> >> > > shorter in the horizontal direction". Then the person keeps >> >> > > demanding >> >> > > a physical explanation, and you say you just rotated the ladder, >> >> > > so >> >> > > it >> >> > > takes up a bit more space in the vertical and less in the >> >> > > horizontal >> >> > > but the total length of the ladder didn't change. >> >> >> > In this case you are not fitting the length of the ladder through a >> >> > narrow door way. You are fitting a skinny side of the ladder through >> >> > a >> >> > wider door way. >> >> > This is not the same as an 80 ft long material pole can fit into a >> >> > 40 >> >> > ft long material barn with both doors close simultaneously. In this >> >> > case material contraction must occur. That's thee reason why modern >> >> > interpretation of length contraction in Sr is merely a geometric >> >> > effect instead of material or physical effect as asserted by the >> >> > runts of the SRians such as PD and you. >> >> >> "Material" does not mean the same thing as "physical", Ken. >> >> This has been pointed out even in the common dictionary. >> >> If you can't let go of your mistakes, Ken, you'll never get off square >> >> one. >> >> > Physical is material....is one of the definitions in my dictionary. >> >> My dictionary says it is relating to the human body (as opposed to mind >> or >> spirit), or involving bodily contact. So if you mean length contraction >> in >> SR is not physical because it does not involve human body contact, then >> I'd >> agree. >> >> In any case, SR says the all the atoms of a moving rod are closer >> together >> (in the frame of a relatively moving observer). ie. that the spatial >> distance between them (at any given time) is shorter than when the rod is >> at >> rest. That sounds 'physically' shorter to me. > > Hey idiot I'm no idiot, as you know. But I'll respond to you anyway. > do you realize that you were describing material length > contraction and not merely geometric projection contraction? The geometric projection results in the atoms being closer together in the frame in which the rod is moving. As I said above. The effect of the geometric projection (rotation) is that the atoms physically get closer. Geometric operations can have physical results. Like rotating a ladder to fit through a doorway. > If > material length contraction occur how come from the pole frame point > of view there is no material length contraction There is a unity projection from pole frame to pole frame .. so no change as a result > and thus it is not > able to fit into the barn? It fits in the barn in the barn frame at some time in the barn frame. There is no time in the pole frame where that is true. That is due to the differences in time in those two frames > Do you realize that material length > contraction is frame independent? Depends on what you mean by 'length'. What is your definition of the length of a rod?
From: Inertial on 15 Feb 2010 23:13 "mpalenik" <markpalenik(a)gmail.com> wrote in message news:bfa9b67b-1e0f-43f1-9b46-1a3dc9027e5b(a)c28g2000vbc.googlegroups.com... > If you have people that live on a little, flat world > sitting in our 3 dimensional space, who can only percieve the things > that exist inside of their little 2 dimensional world, when something > rotates into that third dimension, they'll go "what the heck just > happened? That doesn't look like any rotation I've ever seen." Hehehe .. it's so fun stirring up flatlanders like that, just to see the expressions on the flat little faces. It's the same sort of fun as cow tipping .. only they don't go "moo" :):):)
From: mpalenik on 15 Feb 2010 23:18
On Feb 15, 11:13 pm, "Inertial" <relativ...(a)rest.com> wrote: > "mpalenik" <markpale...(a)gmail.com> wrote in message > > news:bfa9b67b-1e0f-43f1-9b46-1a3dc9027e5b(a)c28g2000vbc.googlegroups.com... > > > If you have people that live on a little, flat world > > sitting in our 3 dimensional space, who can only percieve the things > > that exist inside of their little 2 dimensional world, when something > > rotates into that third dimension, they'll go "what the heck just > > happened? That doesn't look like any rotation I've ever seen." > > Hehehe .. it's so fun stirring up flatlanders like that, just to see the > expressions on the flat little faces. It's the same sort of fun as cow > tipping .. only they don't go "moo" :):):) Well, I wouldn't know, since I grew up in the city. |