Schneibster Posted February 23, 2014 Share Posted February 23, 2014 (edited) Yes, really, if you "believe in" relativity. Lizzy, this is why the light cone is 45 degrees. It's a postulate of relativity. It's like zero, or the meaning of +, or of (). You could maybe get more information from the philosophers but my experience suggests you'll wind up knowing less than you do now. Edited February 23, 2014 by Schneibster Link to comment Share on other sites More sharing options...
studiot Posted February 23, 2014 Share Posted February 23, 2014 Schneibster Please explain why the Lorentz transform can change time into space After you explain what the v is in your equations. I have asked several times now. But in that case I rest my case: time is measured in terms of change - if you don't have a changing thing, you can't measure time. And if you can't measure time, you don't have a way of putting anything on a t axis. Not at all. xyzt. You can changes any of these. C. Changes in xyz are measured in metres; changes in t are measured in seconds. No magic here. However there may be no change at all. It is fundamental that the coordinates represent independent variables. Link to comment Share on other sites More sharing options...
Lizzie L Posted February 23, 2014 Share Posted February 23, 2014 (edited) Well, the light cone is 45% if you choose light-[insert time unit here] for the spatial axes and [insert the same time unit here] for the time axis. It's not a postulate so much as a convenience. And it doesn't put the spatial dimensions into the same units as the time axis. The spatial dimensions have units of distance and the time axis has units of time. Changes in xyz are measured in metres; changes in t are measured in seconds. No magic here. However there may be no change at all. You seem to me to be contradicting yourself, but I'll leave it there until we get some more input. ETA: these self-aggregating posts are rather cool, but I got confused as to who this response was from! OK, so I agree with this. Schneibster seems to disagree. Edited February 23, 2014 by Lizzie L Link to comment Share on other sites More sharing options...
Schneibster Posted February 23, 2014 Share Posted February 23, 2014 (edited) After you explain what the v is in your equations. I have asked several times now. That's simple: it's this fictitious thing called "velocity;" some people think it's somehow "the same" as rapidity, which is rotation in the xt, yt, and zt planes of spacetime. It's kind of obsolete, but we keep converting things to it and pretending space and time are different even though Einstein told us a hundred years ago they're not. Well, the light cone is 45% if you choose light-[insert time unit here] for the spatial axes and [insert the same time unit here] for the time axis. It's not a postulate so much as a convenience. And it doesn't put the spatial dimensions into the same units as the time axis. The spatial dimensions have units of distance and the time axis has units of time. You seem to me to be contradicting yourself, but I'll leave it there until we get some more input. ETA: these self-aggregating posts are rather cool, but I got confused as to who this response was from! OK, so I agree with this. Schneibster seems to disagree. Ummm, that didn't help much. You seem to be having a lot of trouble with the math. Edited February 23, 2014 by Schneibster Link to comment Share on other sites More sharing options...
swansont Posted February 23, 2014 Share Posted February 23, 2014 I believe we are mystified by space. Length and space aren't the same thing. I don't think so. We haven't reach the edge of human understanding. That's not what moo claimed, though. Link to comment Share on other sites More sharing options...
Lizzie L Posted February 23, 2014 Share Posted February 23, 2014 (edited) Ummm, that didn't help much. No, it didn't. I'm finding the "speed of time" concept incoherent, and the definition of the speed of light as second/second equally so, and I don't see how it flows from anything you've posted or my admittedly crude understanding of relativity. And you haven't persuaded me that the units on the x, y and z units are the same as the units on the t axis. But my ear is open like a greedy shark, to catch the tunings of a voice divine. (Keats, heh). Edited February 23, 2014 by Lizzie L Link to comment Share on other sites More sharing options...
Schneibster Posted February 23, 2014 Share Posted February 23, 2014 Lorentz transform proves space and time are equivalent by direct transformation. Equations governing transformation of space to time are provided. You cannot transform dissimilar things, period. Please pay attention to the math. Link to comment Share on other sites More sharing options...
studiot Posted February 23, 2014 Share Posted February 23, 2014 That's simple: it's this fictitious thing called "velocity;" some people think it's somehow "the same" as rapidity Yes a velocity indeed, but what velocity in what coordinate system? That is the key question. I really don't care or see that it is relevant that some people have invented yet another superfluous new word called rapidity. Link to comment Share on other sites More sharing options...
Schneibster Posted February 23, 2014 Share Posted February 23, 2014 (edited) No, it didn't. I'm finding the "speed of time" concept incoherent, and the definition of the speed of light as second/second equally so, and I don't see how it flows from anything you've posted or my admittedly crude understanding of relativity. And you haven't persuaded me that the units on the x, y and z units are the same as the units on the t axis. But my ear is open like a greedy shark, to catch the tunings of a voice divine. (Keats, heh). Well, I hate to say it but I'm finding you just don't understand the math. You also appear not to understand the meaning of "postulate." Nor the meaning of the fact that time calculations work perfectly when you use hyperbolic trig. And the equations are obviously those of a rotation. How can you "rotate in the xt, yt, and/or zt planes" and not rotate time into space? What do you expect to perceive? If you expect anything different than you see now, you're wrong- unless you look out at the universe. That's the meaning of the Principle of Special Relativity, another postulate of the Theory of Special Relativity. So if you go fast enough, you will "see time," and it will look just like space to you. Time and space are the same thing. This is a fact. We know for sure. It's not some nebulous bunch of BS, it's a solid mathematical theory invented by a math genius in the last century named Einstein. It remains uncontradicted in that time, ever. No experiment has ever caused a continuing question about a postulate, or a theoretical finding, of Special Relativity. It is one of the postulates of the Standard Model of Particle Physics, and of the Standard Model of Cosmology. (In that it exceeds even its progeny, the far more powerful Theory of General Relativity, which has not been integrated into the SM of Particle Physics, along with its more far ranging Principle of General Relativity and Equivalence). If you're waiting for an expert that will tell you any of those things are wrong you'll be waiting a long time, Lizzie. Yes a velocity indeed, but what velocity in what coordinate system? That is the key question. I really don't care or see that it is relevant that some people have invented yet another superfluous new word called rapidity. It's not superfluous; velocity is. Rapidity is the way you measure movement in relativity; velocity is outmoded. I suppose you could use β, which is v/c, that is the fraction of c of your "velocity," or γ, which is the Lorentz Factor, √(1 - β2), if you insist on using faux Newtonian physics. Edited February 23, 2014 by Schneibster Link to comment Share on other sites More sharing options...
Lizzie L Posted February 23, 2014 Share Posted February 23, 2014 Lorentz transform proves space and time are equivalent by direct transformation. Equations governing transformation of space to time are provided. You cannot transform dissimilar things, period. Please pay attention to the math. I'm paying attention to the math, but I'm not seeing space and time proved equivalent. I'm not seeing the transform as transforming space into time. I'm seeing them as transforming an event from the reference frame of one observer into the reference frame of another. Link to comment Share on other sites More sharing options...
studiot Posted February 23, 2014 Share Posted February 23, 2014 (edited) Schneibster Well, I hate to say it but I'm finding you just don't understand the math. Perhaps that's because you are not setting out your 'math' correctly or conventionally. Bald statement of equations, without specifying variables and constants constraints and limits of applicability and developing a train of mathematical argument (proof) does not make 'math'. It's not superfluous; velocity is. Rapidity is the way you measure movement in relativity; velocity is outmoded. So you are not going to answer my question? Edited February 23, 2014 by studiot Link to comment Share on other sites More sharing options...
Lizzie L Posted February 23, 2014 Share Posted February 23, 2014 Well, I hate to say it but I'm finding you just don't understand the math. You also appear not to understand the meaning of "postulate." Nor the meaning of the fact that time calculations work perfectly when you use hyperbolic trig. And the equations are obviously those of a rotation. How can you "rotate in the xt, yt, and/or zt planes" and not rotate time into space? Because you are also rotating the t axis. You aren't rotating time into space. You end up with a new set of xyz axes and a new t axis, and the units remain distance on the xyz and time on the t. What do you expect to perceive? If you expect anything different than you see now, you're wrong- unless you look out at the universe. That's the meaning of the Principle of Special Relativity, another postulate of the Theory of Special Relativity. So if you go fast enough, you will "see time," and it will look just like space to you. Time and space are the same thing. This is a fact. We know for sure. It's not some nebulous bunch of BS, it's a solid mathematical theory invented by a math genius in the last century named Einstein. It remains uncontradicted in that time, ever. No experiment has ever caused a continuing question about a postulate, or a theoretical finding, of Special Relativity. It is one of the postulates of the Standard Model of Particle Physics, and of the Standard Model of Cosmology. (In that it exceeds even its progeny, the far more powerful Theory of General Relativity, which has not been integrated into the SM of Particle Physics, along with its more far ranging Principle of General Relativity and Equivalence). If you're waiting for an expert that will tell you any of those things are wrong you'll be waiting a long time, Lizzie. I'm a patient woman 1 Link to comment Share on other sites More sharing options...
Schneibster Posted February 23, 2014 Share Posted February 23, 2014 I'm paying attention to the math, but I'm not seeing space and time proved equivalent. I'm not seeing the transform as transforming space into time. I'm seeing them as transforming an event from the reference frame of one observer into the reference frame of another. x → √(1 - (v2/c2)) * (x - vt) doesn't look like transforming x in to some x and some t, to you? Really? Because you are also rotating the t axis. You aren't rotating time into space. You end up with a new set of xyz axes and a new t axis, and the units remain distance on the xyz and time on the t. That's one observer's viewpoint. Not both. You're ignoring the main observer. Link to comment Share on other sites More sharing options...
studiot Posted February 23, 2014 Share Posted February 23, 2014 (edited) doesn't look like transforming x in to some x and some t, to you? No it just looks like nonsense to me since the terms have not been defined. since you won't do it I will. If your equation is valid it must hold for every value of v : v<c. So I define v=0. Then your equation tells me that x = x Whoopee!!! Not a rotation or other animal in sight. Edited February 23, 2014 by studiot Link to comment Share on other sites More sharing options...
Schneibster Posted February 23, 2014 Share Posted February 23, 2014 (edited) Perhaps that's because you are not setting out your 'math' correctly or conventionally. Whose convention? You appear unfamiliar with the mathematics of the Lorentz transform, which are far more basic than relativity. I'm using math from John Baez, who is an expert relativist and mathematician and lectures at the University of California, where he is a professor of mathematics. He's probably best known for his "Crackpot Index," a humorous look at internet nutjobs, but he is also an expert in exactly the areas we're discussing. What "correctness" do you assert John Baez is violating? Or what "conventions?" Please elaborate. No it just looks like nonsense to me since the terms have not been defined. So you can't do the math. I don't need to define anything. Do you deny that operation transforms x in to partly x and partly t? Never mind what they mean yet- let's just get the math agreed to. So you are not going to answer my question? I did. No it just looks like nonsense to me since the terms have not been defined. since you won't do it I will. If your equation is valid it must hold for every value of v : v<c. So I define v=0. Then your equation tells me that x = x Whoopee!!! Not a rotation or other animal in sight. Which is precisely what it should say. If your rapidity is zero in x then your Lorentz transform in x is x' = x. Or in the other notation x → x. Edited February 23, 2014 by Schneibster Link to comment Share on other sites More sharing options...
studiot Posted February 23, 2014 Share Posted February 23, 2014 (edited) Since you introduced the equation (by copying someone else) I'm waiting for you to do some actual mathematics. I have asked you at least five times to explain v, which you also introduced. So far you have told me it is superfluous, and ignored every request to explain in full what this variable represents. So, once again, I am asking you to explain yourself. Why for instance introduce v if it is superfluous? Edited February 23, 2014 by studiot Link to comment Share on other sites More sharing options...
Lizzie L Posted February 23, 2014 Share Posted February 23, 2014 x → √(1 - (v2/c2)) * (x - vt) doesn't look like transforming x in to some x and some t, to you? No, it doesn't. The units in v2/c2 cancel (as both are velocities) leaving us with x-vt which is the same as a galilean transform - you just move the thing along the original x axis by the amount of distance that the thing will have travelled in time t. And a square root, but that's not going to turn space into time. Link to comment Share on other sites More sharing options...
Schneibster Posted February 23, 2014 Share Posted February 23, 2014 (edited) Since you introduced the equation (by copying someone else) I'm waiting for you to do some actual mathematics. I have asked you at least five times to explain v, which you also introduced. So far you have told me it is superfluous, and ignored every request to explain in full what this variable represents. So, once again, I am asking you to explain yourself. Why for instance introduce v if it is superfluous? Sorry, if you can't do the math I won't discuss equations with you. No, it doesn't. The units in v2/c2 cancel (as both are velocities) leaving us with x-vt which is the same as a galilean transform - you just move the thing along the original x axis by the amount of distance that the thing will have travelled in time t. And a square root, but that's not going to turn space into time. LOL I'm sorry, Lizzie, you too. Learn the math then come back. This is a waste of time. You're just making stuff up to object to in order to harass me. One more like this and you go on ignore. One more try for you both: If you have to remove vt from x, then you have to add it to t. That's how the transform works, mathematically. Perhaps if you think of them as simultaneous equations it will help. Edited February 23, 2014 by Schneibster -1 Link to comment Share on other sites More sharing options...
Lizzie L Posted February 23, 2014 Share Posted February 23, 2014 Let's take a simple Galilean transform for two reference frames, and an object travelling at velocity v along the shared x axis: At any given time, the x coordinates of the object in reference frame xyz will be given by x minus the velocity of the object times the time it's been travelling. So if it's been travelling at one mile an hour for one hour, we subtract 1 mile off the x' axis to get the coordinates on the x axis. And the other coordinates will, in this example, be the same in both. So the transform works just fine, and doesn't convert spatial units into time. 3 miles minus the distance travelled by object x in one hour is still a distance. Link to comment Share on other sites More sharing options...
sheever Posted February 23, 2014 Share Posted February 23, 2014 Link to comment Share on other sites More sharing options...
Schneibster Posted February 23, 2014 Share Posted February 23, 2014 (edited) Another way of saying this is to say that the Pythagorean distance formula in Minkowski spacetime is d = x2 + y2 + z2- c2t2 Note I bolded the negative in the last term. This definition of "d" is called the "spacetime interval" and is as important in spacetime as the Pythagorean distance d is in space. Note the inclusion of the c coefficient in the time dimension's term. Again, this is why I say we move through time at the speed of light. It says so in plain mathematics right freaking there, no questions, no doubts, no BS. Edited February 23, 2014 by Schneibster Link to comment Share on other sites More sharing options...
sheever Posted February 23, 2014 Share Posted February 23, 2014 (edited) time is the consequence of the breaking symmetry.it involves analog competition on macro level and quantise time to linear. natural computation. everything else is a deadend. to explain better t is the summing of the fractions of Z. X and Y axis doesnt exist without the Z fractions.X and Y is phase shifting relative to everything else trough the process of its own rotation growth if you want arguing you will have to eliminate wave function of anything at the first place also spin. Edited February 23, 2014 by sheever Link to comment Share on other sites More sharing options...
Schneibster Posted February 23, 2014 Share Posted February 23, 2014 (edited) Let's take a simple Galilean transform for two reference frames, and an object travelling at velocity v along the shared x axis: At any given time, the x coordinates of the object in reference frame xyz will be given by x minus the velocity of the object times the time it's been travelling. So if it's been travelling at one mile an hour for one hour, we subtract 1 mile off the x' axis to get the coordinates on the x axis. And the other coordinates will, in this example, be the same in both. So the transform works just fine, and doesn't convert spatial units into time. 3 miles minus the distance travelled by object x in one hour is still a distance. You left out time. The reason the Galilei transform is incorrect is because it fails to correct for the Lorentz factor. It is incorrect because it doesn't include time in the calculations for x. Surely you understand that the Lorentz transform replaced the Galilei transform, except in the limit of low rapidity? Did you realize that? That's why physicists say that relativity "replaced" Newtonian/Galilean mechanics. Basically, you just said you don't "believe in" relativity because Newton. And also Galileo. Also. Too. Edited February 23, 2014 by Schneibster Link to comment Share on other sites More sharing options...
Lizzie L Posted February 23, 2014 Share Posted February 23, 2014 No, I didn't leave out time. See the part where it says "one hour"? Anyway, Schneibster, I didn't come here to wrangle with you. I followed your link, and it looked like a cool forum and the nature of time is sort of in my baileywick, after a fashion. So I'll eave the math argument to better mathematicians than I. I'm going to stick to my guns, though, and say that in an unchanging world, time would have no meaning, or, in other words, that time only makes sense in world in which things change. And the fact that our units of time require reference to some oscillator seems to me to demonstrate that quite well. As for the direction of time - I think that is largely an artefact of what we are privy to as observers, and what we can predict from what we are given in the present. Link to comment Share on other sites More sharing options...
Schneibster Posted February 23, 2014 Share Posted February 23, 2014 (edited) No, I didn't leave out time. Yes, you did. You used the Galilei transform. See the Lorentz transform. Post 156. Note that it is not the same as the Galilei transform. Note that it is degenerate with it when the velocity/rapidity is zero. Note that time becomes a more and more important element the faster you go. You treated time as if it has no relation to space when they actually do. That's because you used the wrong transform, one that is outdated, obsolete, and known false. The Galilei transform is incorrect because it does not include the Lorentz factor. The correct transform is the Lorentz Transform. That was proven well over a hundred years ago. You're not going to see any other proof. Everyone knows I'm right. You attempting to prove stuff with the Galilei transform is you admitting you don't understand relativity at all. I really don't think you've understood why and how the twin "paradox" and the constancy of the speed of light really work. And you've been fighting well-established physics a long time now, Lizzie. I really think you need to go do some reading/learning. I can recommend some books. I've recommended them to you before and you've ignored me. I won't put you on ignore for not understanding. Only for willfully denying. Edited February 23, 2014 by Schneibster Link to comment Share on other sites More sharing options...
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