Electron and proton attraction by opposite charge
in [Relativity]
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From: ben6993 on 13 May 2010 11:01 On May 13, 2:54 pm, ben6993 <ben6...(a)hotmail.com> wrote: > On May 13, 12:02 pm, "Androcles" <Headmas...(a)Hogwarts.physics_z> > wrote: > > > > > > > "ben6993" <ben6...(a)hotmail.com> wrote in message > > >news:2244ee3e-4794-48bc-8ae1-5c78c491b4cf(a)b7g2000yqk.googlegroups.com... > > On May 13, 10:01 am, "Androcles" <Headmas...(a)Hogwarts.physics_z> > > wrote: > > > > "ben6993" <ben6...(a)hotmail.com> wrote in message > > > >news:7f5a614f-5ea0-43f7-abe9-085678938f39(a)n15g2000yqf.googlegroups.com.... > > > > <snip to the nitty gritty> > > > > Hi Androcles > > > > Using Einstein's (1905) two frames: K (stationary, t, x, y, z) and k > > > (moving, tau, xi, eta, zeta). > > > Let Androcles make measurements in the stationary frame K. > > > Assume that the speed v is sufficient (approx. 0.866c) to produce a > > > measured length in K which is half of what it is in k. > > > In assuming this, it is needed to show that Androcles measures the > > > length as x, where x is half of the length measured as xi. > > > I.e. need to show that x = 0.5 xi. > > > > - - - -- > > > > Einstein's formula is xi = beta (x-vt) > > > At t=0, xi=beta x > > > > This is Einstein's beta, where beta = 1/sqrt(1-v^2/c^2) > > > > sqrt(1-v^2/c^2) = 0.5 > > > > so beta = 1/0.5 = 2 > > > > so in Einsein's formula xi= beta x, therefore xi = 2x. > > > > xi=2x, > > > therefore x = 0.5 xi which is what we set out to prove. > > > ============================================= > > > Very good. You have indeed proven that Einstein's moving frame is > > > twice as long as his stationary frame at your chosen speed. > > > Well done, we agree, and it seems your round tuit has had the > > > desired result. > > > > If you go faster you'll have further to go. > > > ============================================= > > > So Einstein's equations seem to me to agree with the Lorentz formula. > > > =============================================== > > > You really should learn the difference between multiplication and > > > division, which is taught in third grade. Have another round tuit. > > > > Lorentz claims L = L0 * sqrt(1 - v^2/c^2) > > > Einstein claims L = L0 / sqrt(1 - v^2/c^2) > > > > L0 is the length in Lorentz's aether frame > > > and > > > L0 (=x-vt) is the length in Einstein's stationary frame (which you've now > > > proven). > > > > Can you see that Lorentz's L is 0.5 and Einstein's L is 2 at your chosen > > > speed? > > > > =============================================== > > > I am disappointed, Androcles, as I had put off doing this previously > > > because I had thought it was complicated. Unless I am overlooking > > > something complicated? > > > ============================================ > > > Well, yes. I do understand that division is more complicated than > > > multiplication and both Einstein and Lorentz were clowns, but I'm > > > please to see that you've proven Einstein to be the clown with > > > the more ridiculous bigger feet to trip over and fall flat on his face. > > > L0 is the length in k (where measurements are in tau and xi) > > ============================================ > > Nope. L0 is the reference length in the "stationary" frame K. > > You have it backwards. > > Because the whole Earth is moving around the Sun (and carrying > > us and all our experiments with it) it is moving in the aether or > > "stationary" frame. The aether is the medium in which light is > > supposedly "waving", and the diameter of the Earth is L, it is > > moving. Lorentz imagined that the aether pressure on the moving > > Earth and all its molecules (you'll feel a pressure on your hand if > > you put it out of the car window at 60 mph) would compress the > > Earth like one hammer crushes an orange without an anvil, so > > L = L0 * beta. > > In other words Lorentz theorised he could ignore Newton's third law. > > > L is the length in K (where Androcles is measuring in x and t) > > > ============================================== > > Nope. > > > "It is essential to have time defined by means of stationary clocks in the > > stationary system, and the time now defined being appropriate to the > > stationary system we call it ``the time of the stationary system.'' - Last > > sentence of section 1 inhttp://www.fourmilab.ch/etexts/einstein/specrel/www/ > > together with > > http://www.fourmilab.ch/etexts/einstein/specrel/www/figures/img53.gif > > I (and you) are moving through Einstein's stationary space, we measure xi > > and tau. > > Our speed in stationary space is the distance the Earth moves around the > > Sun, > > 150,000,000 kilometers multiplied by 2pi, and divided by one year. That > > comes > > out at about 0.0001c. > > ============================================== > > > so replace L0 by xi and replace L by x. > > ================================================ > > Nope. > > replace L0 (which you cannot measure without stopping the Earth) with x-vt. > > > Lorentz claims L = L0 * sqrt(1 - v^2/c^2) > > becomes x = xi *sqrt(1 - v^2/c^2) > > ================================================ > > Nope, L0 becomes x' = x-vt > > and Lorentz claims x' = xi / sqrt(1 - v^2/c^2) > > but Einstein claims xi = x' / sqrt (1-v^2/c^2) > > > ie x=xi/beta (Einsteins beta = 1/sqrt(1 - v^2/c^2)) > > > ================================================== > > Nope, > > xi = x' * beta. (Einstein's beta = 1/sqrt(1 - v^2/c^2), not sqrt(1 - > > v^2/c^2) ) > > > ie xi=beta x > > > ================================================= > > Not quite, xi = beta x', > > where x' = x-vt > > > OK, as this is Einstein's formula. > > ============================= > > Yep, but it isn't Lorentz's formula. > > > You say that Einstein claims that L = L0 / sqrt(1 - v^2/c^2) > > =============================================== > > Yep. Here it is: > > http://www.fourmilab.ch/etexts/einstein/specrel/www/figures/img53.gif > > I don't claim what I can't quote. > > > ie x = xi/sqrt(1 - v^2/c^2) > > ie x= xi beta (Einsteins beta = 1/sqrt(1 - v^2/c^2)) > > NOT OK, as this is not Einstein's formula. > > ================================================= > > True enough, x isn't x' = x-vt. > > > Einstein's formula is xi=beta x > > ==================================================== > > Nope. > > Einstein's formula is xi=beta x' > > Here it is: > > http://www.fourmilab.ch/etexts/einstein/specrel/www/figures/img53.gif > > I don't claim what I can't quote. > > > so you should not think that that Einstein says that L=L0 / sqrt(1 - > > v^2/c^2). > > ================================================= > > Yes I should because he did say that. > > > Or you should make it clear to me why you think that this is what > > Einstein is saying. > > =================================================== > > I've been making it as clear as I can. > > Perhaps this will help: > > http://www.androcles01.pwp.blueyonder.co.uk/Smart/x'=x-vt.gif > > "If we place x'=x-vt, it is clear that a point at rest in the system k must > > have a system of values x', y, z, independent of time." -- Einstein, Section > > 3.- Hide quoted text - > > > - Show quoted text - > > You mentioned aether wrt Lorentz. I don't know much about aether and > don't want to go there, unless my arm is twisted. Not yet anyhow. > There doesn't seem to be much point in having frame k if we don't use > it. We did not previously specify that the object being measured was > at rest in frame k, but I was assuming it. > > Say L0 is a measurement of the length of a stationary object in the > stationary frame K. Ie x=L0. > If you re-measure, in stationary frame K (t, x, y, z), the length of > the object when the object is moving within frame K then the object > will no longer have length L0 in frame K. Ie x <>L0. If the object > is stationary within frame k and frame k itself is moving at speed v > compared to frame K, the object can be measured in moving frame k > (tau, xi, eta, zeta). Ie xi=L0. > > I earlier used Einstein's equations with t=0. You are bringing time > into the explanations and its seems perhaps that you are going into a > path where you want me to check Einstein's derivation of his > equations. I was intending to use his equations, not derive them. > But to be more general I will derive the required result for any time > t. > > Say the nearest point of an object at rest in frame k is at xi0 and > the object's furthest point is at xi1, at any time tau measured in > moving frame k. > > And as the stationary object in frame k is of length L0, then L0=xi1- > xi0. > > Using Einstein's equation with beta=2, [ie sqrt(1 - v^2/c^2) = 0.5]: > xi=2(x-vt) > therefore -2vt= xi-2x. > > For the nearest point of the object > ie at xi=xi0 and x=x0 > therefore -2vt= xi0-2x0 > > For the furthest point of the object > ie at xi=xi1 and x=x1 > therefore -2vt= xi1-2x1 > > so xi0-2x0 = xi1-2x1 = L0 + xi0 -2x1 > ie -2x0 = L0 + -2x1 > L0 = 2(x1-x0) +2L > ie L = 0.5 L0 > where L is the length of the object as measured in the stationary > frame K. > This gives the contracted length of one half the length measured when > at rest.- Hide quoted text - > > - Show quoted text - Sorry for a typo of a + sign instead of an = sign It should have been L0 = 2(x1-x0) = 2L, not L0 = 2(x1-x0) +2L The last six lines should therefore have been: > L0 = 2(x1-x0) = 2L > ie L = 0.5 L0 > where L is the length of the object as measured in the stationary > frame K. > This gives the contracted length of one half the length measured when > at rest.
From: Androcles on 13 May 2010 14:44 "ben6993" <ben6993(a)hotmail.com> wrote in message news:65559e77-7726-40bd-ab96-817426d75b68(a)e1g2000yqe.googlegroups.com... On May 13, 2:54 pm, ben6993 <ben6...(a)hotmail.com> wrote: > On May 13, 12:02 pm, "Androcles" <Headmas...(a)Hogwarts.physics_z> > wrote: > > > > > > > "ben6993" <ben6...(a)hotmail.com> wrote in message > > >news:2244ee3e-4794-48bc-8ae1-5c78c491b4cf(a)b7g2000yqk.googlegroups.com... > > On May 13, 10:01 am, "Androcles" <Headmas...(a)Hogwarts.physics_z> > > wrote: > > > > "ben6993" <ben6...(a)hotmail.com> wrote in message > > > >news:7f5a614f-5ea0-43f7-abe9-085678938f39(a)n15g2000yqf.googlegroups.com... > > > > <snip to the nitty gritty> > > > > Hi Androcles > > > > Using Einstein's (1905) two frames: K (stationary, t, x, y, z) and k > > > (moving, tau, xi, eta, zeta). > > > Let Androcles make measurements in the stationary frame K. > > > Assume that the speed v is sufficient (approx. 0.866c) to produce a > > > measured length in K which is half of what it is in k. > > > In assuming this, it is needed to show that Androcles measures the > > > length as x, where x is half of the length measured as xi. > > > I.e. need to show that x = 0.5 xi. > > > > - - - -- > > > > Einstein's formula is xi = beta (x-vt) > > > At t=0, xi=beta x > > > > This is Einstein's beta, where beta = 1/sqrt(1-v^2/c^2) > > > > sqrt(1-v^2/c^2) = 0.5 > > > > so beta = 1/0.5 = 2 > > > > so in Einsein's formula xi= beta x, therefore xi = 2x. > > > > xi=2x, > > > therefore x = 0.5 xi which is what we set out to prove. > > > ============================================= > > > Very good. You have indeed proven that Einstein's moving frame is > > > twice as long as his stationary frame at your chosen speed. > > > Well done, we agree, and it seems your round tuit has had the > > > desired result. > > > > If you go faster you'll have further to go. > > > ============================================= > > > So Einstein's equations seem to me to agree with the Lorentz formula. > > > =============================================== > > > You really should learn the difference between multiplication and > > > division, which is taught in third grade. Have another round tuit. > > > > Lorentz claims L = L0 * sqrt(1 - v^2/c^2) > > > Einstein claims L = L0 / sqrt(1 - v^2/c^2) > > > > L0 is the length in Lorentz's aether frame > > > and > > > L0 (=x-vt) is the length in Einstein's stationary frame (which you've > > > now > > > proven). > > > > Can you see that Lorentz's L is 0.5 and Einstein's L is 2 at your > > > chosen > > > speed? > > > > =============================================== > > > I am disappointed, Androcles, as I had put off doing this previously > > > because I had thought it was complicated. Unless I am overlooking > > > something complicated? > > > ============================================ > > > Well, yes. I do understand that division is more complicated than > > > multiplication and both Einstein and Lorentz were clowns, but I'm > > > please to see that you've proven Einstein to be the clown with > > > the more ridiculous bigger feet to trip over and fall flat on his > > > face. > > > L0 is the length in k (where measurements are in tau and xi) > > ============================================ > > Nope. L0 is the reference length in the "stationary" frame K. > > You have it backwards. > > Because the whole Earth is moving around the Sun (and carrying > > us and all our experiments with it) it is moving in the aether or > > "stationary" frame. The aether is the medium in which light is > > supposedly "waving", and the diameter of the Earth is L, it is > > moving. Lorentz imagined that the aether pressure on the moving > > Earth and all its molecules (you'll feel a pressure on your hand if > > you put it out of the car window at 60 mph) would compress the > > Earth like one hammer crushes an orange without an anvil, so > > L = L0 * beta. > > In other words Lorentz theorised he could ignore Newton's third law. > > > L is the length in K (where Androcles is measuring in x and t) > > > ============================================== > > Nope. > > > "It is essential to have time defined by means of stationary clocks in > > the > > stationary system, and the time now defined being appropriate to the > > stationary system we call it ``the time of the stationary system.'' - > > Last > > sentence of section 1 > > inhttp://www.fourmilab.ch/etexts/einstein/specrel/www/ > > together with > > http://www.fourmilab.ch/etexts/einstein/specrel/www/figures/img53.gif > > I (and you) are moving through Einstein's stationary space, we measure > > xi > > and tau. > > Our speed in stationary space is the distance the Earth moves around the > > Sun, > > 150,000,000 kilometers multiplied by 2pi, and divided by one year. That > > comes > > out at about 0.0001c. > > ============================================== > > > so replace L0 by xi and replace L by x. > > ================================================ > > Nope. > > replace L0 (which you cannot measure without stopping the Earth) with > > x-vt. > > > Lorentz claims L = L0 * sqrt(1 - v^2/c^2) > > becomes x = xi *sqrt(1 - v^2/c^2) > > ================================================ > > Nope, L0 becomes x' = x-vt > > and Lorentz claims x' = xi / sqrt(1 - v^2/c^2) > > but Einstein claims xi = x' / sqrt (1-v^2/c^2) > > > ie x=xi/beta (Einsteins beta = 1/sqrt(1 - v^2/c^2)) > > > ================================================== > > Nope, > > xi = x' * beta. (Einstein's beta = 1/sqrt(1 - v^2/c^2), not sqrt(1 - > > v^2/c^2) ) > > > ie xi=beta x > > > ================================================= > > Not quite, xi = beta x', > > where x' = x-vt > > > OK, as this is Einstein's formula. > > ============================= > > Yep, but it isn't Lorentz's formula. > > > You say that Einstein claims that L = L0 / sqrt(1 - v^2/c^2) > > =============================================== > > Yep. Here it is: > > http://www.fourmilab.ch/etexts/einstein/specrel/www/figures/img53.gif > > I don't claim what I can't quote. > > > ie x = xi/sqrt(1 - v^2/c^2) > > ie x= xi beta (Einsteins beta = 1/sqrt(1 - v^2/c^2)) > > NOT OK, as this is not Einstein's formula. > > ================================================= > > True enough, x isn't x' = x-vt. > > > Einstein's formula is xi=beta x > > ==================================================== > > Nope. > > Einstein's formula is xi=beta x' > > Here it is: > > http://www.fourmilab.ch/etexts/einstein/specrel/www/figures/img53.gif > > I don't claim what I can't quote. > > > so you should not think that that Einstein says that L=L0 / sqrt(1 - > > v^2/c^2). > > ================================================= > > Yes I should because he did say that. > > > Or you should make it clear to me why you think that this is what > > Einstein is saying. > > =================================================== > > I've been making it as clear as I can. > > Perhaps this will help: > > http://www.androcles01.pwp.blueyonder.co.uk/Smart/x'=x-vt.gif > > "If we place x'=x-vt, it is clear that a point at rest in the system k > > must > > have a system of values x', y, z, independent of time." -- Einstein, > > Section > > 3.- Hide quoted text - > > > - Show quoted text - > > You mentioned aether wrt Lorentz. I don't know much about aether and > don't want to go there, unless my arm is twisted. Not yet anyhow. Just giving you some history. Do as you like with it. > There doesn't seem to be much point in having frame k if we don't use > it. We did not previously specify that the object being measured was > at rest in frame k, but I was assuming it. See below. > Say L0 is a measurement of the length of a stationary object in the > stationary frame K. Ie x=L0. Correct. > If you re-measure, in stationary frame K (t, x, y, z), the length of > the object when the object is moving within frame K Look at this gif: http://www.androcles01.pwp.blueyonder.co.uk/Wave/k_frame.gif First, the k-frame moves in x. The ball moves with it. Second, the k-frame moves in y. Third, the k-frame moves in z. Fourth, the k-frame rotates about its origin. The ball is fixed (at rest) in the k-frame, so it "moves in the K-frame", but you cannot tell that it rotated because it has no features, or that it rotates ABOUT THE ORIGIN of the k-frame. If I say "the ball rotates" you might think I meant it rotates about its own axis, but it actually rotates about the z-axis of the k-frame. The frames are invisible mathematical entities, but they are essential to the engineer in describing motion mathematically. The program I used to create that gif is free, you can download it from http://sketchup.google.com/ and discover for yourself just how much the idea of frames is built into graphics. Nothing moves "within a frame". Instead, another frame moves relatively to the former frame. > then the object > will no longer have length L0 in frame K. Ie x <>L0. If the object > is stationary within frame k and frame k itself is moving at speed v > compared to frame K, the object can be measured in moving frame k > (tau, xi, eta, zeta). Ie xi=L0. My gif doesn't change the ball size. > I earlier used Einstein's equations with t=0. You are bringing time > into the explanations and its seems perhaps that you are going into a > path where you want me to check Einstein's derivation of his > equations. Oh yes, certainly I do. You'll never understand nonsense unless you examine it. Get around to it. > I was intending to use his equations, not derive them. Big mistake. That's GIGO, garbage in, garbage out, and what every idiot does. > But to be more general I will derive the required result for any time > t. ================================================= Not for me you won't, I'm not interested in going backwards over old ground. {SNIP} Try to see the forest, you are looking at leaves on a tree. You are getting tied up in knots fumbling with the algebra. Nothing gets contracted, the k-frame gets expanded and Einstein was a bozo.
From: ben6993 on 14 May 2010 09:02 On May 13, 7:44 pm, "Androcles" <Headmas...(a)Hogwarts.physics_z> wrote: > "ben6993" <ben6...(a)hotmail.com> wrote in message > > news:65559e77-7726-40bd-ab96-817426d75b68(a)e1g2000yqe.googlegroups.com... > On May 13, 2:54 pm, ben6993 <ben6...(a)hotmail.com> wrote: > > > On May 13, 12:02 pm, "Androcles" <Headmas...(a)Hogwarts.physics_z> > > wrote: > > > > "ben6993" <ben6...(a)hotmail.com> wrote in message > > > >news:2244ee3e-4794-48bc-8ae1-5c78c491b4cf(a)b7g2000yqk.googlegroups.com.... > > > On May 13, 10:01 am, "Androcles" <Headmas...(a)Hogwarts.physics_z> > > > wrote: > > > > > "ben6993" <ben6...(a)hotmail.com> wrote in message > > > > >news:7f5a614f-5ea0-43f7-abe9-085678938f39(a)n15g2000yqf.googlegroups.com... > > > > > <snip to the nitty gritty> > > > > > Hi Androcles > > > > > Using Einstein's (1905) two frames: K (stationary, t, x, y, z) and k > > > > (moving, tau, xi, eta, zeta). > > > > Let Androcles make measurements in the stationary frame K. > > > > Assume that the speed v is sufficient (approx. 0.866c) to produce a > > > > measured length in K which is half of what it is in k. > > > > In assuming this, it is needed to show that Androcles measures the > > > > length as x, where x is half of the length measured as xi. > > > > I.e. need to show that x = 0.5 xi. > > > > > - - - -- > > > > > Einstein's formula is xi = beta (x-vt) > > > > At t=0, xi=beta x > > > > > This is Einstein's beta, where beta = 1/sqrt(1-v^2/c^2) > > > > > sqrt(1-v^2/c^2) = 0.5 > > > > > so beta = 1/0.5 = 2 > > > > > so in Einsein's formula xi= beta x, therefore xi = 2x. > > > > > xi=2x, > > > > therefore x = 0.5 xi which is what we set out to prove. > > > > ============================================= > > > > Very good. You have indeed proven that Einstein's moving frame is > > > > twice as long as his stationary frame at your chosen speed. > > > > Well done, we agree, and it seems your round tuit has had the > > > > desired result. > > > > > If you go faster you'll have further to go. > > > > ============================================= > > > > So Einstein's equations seem to me to agree with the Lorentz formula. > > > > =============================================== > > > > You really should learn the difference between multiplication and > > > > division, which is taught in third grade. Have another round tuit. > > > > > Lorentz claims L = L0 * sqrt(1 - v^2/c^2) > > > > Einstein claims L = L0 / sqrt(1 - v^2/c^2) > > > > > L0 is the length in Lorentz's aether frame > > > > and > > > > L0 (=x-vt) is the length in Einstein's stationary frame (which you've > > > > now > > > > proven). > > > > > Can you see that Lorentz's L is 0.5 and Einstein's L is 2 at your > > > > chosen > > > > speed? > > > > > =============================================== > > > > I am disappointed, Androcles, as I had put off doing this previously > > > > because I had thought it was complicated. Unless I am overlooking > > > > something complicated? > > > > ============================================ > > > > Well, yes. I do understand that division is more complicated than > > > > multiplication and both Einstein and Lorentz were clowns, but I'm > > > > please to see that you've proven Einstein to be the clown with > > > > the more ridiculous bigger feet to trip over and fall flat on his > > > > face. > > > > L0 is the length in k (where measurements are in tau and xi) > > > ============================================ > > > Nope. L0 is the reference length in the "stationary" frame K. > > > You have it backwards. > > > Because the whole Earth is moving around the Sun (and carrying > > > us and all our experiments with it) it is moving in the aether or > > > "stationary" frame. The aether is the medium in which light is > > > supposedly "waving", and the diameter of the Earth is L, it is > > > moving. Lorentz imagined that the aether pressure on the moving > > > Earth and all its molecules (you'll feel a pressure on your hand if > > > you put it out of the car window at 60 mph) would compress the > > > Earth like one hammer crushes an orange without an anvil, so > > > L = L0 * beta. > > > In other words Lorentz theorised he could ignore Newton's third law. > > > > L is the length in K (where Androcles is measuring in x and t) > > > > ============================================== > > > Nope. > > > > "It is essential to have time defined by means of stationary clocks in > > > the > > > stationary system, and the time now defined being appropriate to the > > > stationary system we call it ``the time of the stationary system.'' - > > > Last > > > sentence of section 1 > > > inhttp://www.fourmilab.ch/etexts/einstein/specrel/www/ > > > together with > > >http://www.fourmilab.ch/etexts/einstein/specrel/www/figures/img53.gif > > > I (and you) are moving through Einstein's stationary space, we measure > > > xi > > > and tau. > > > Our speed in stationary space is the distance the Earth moves around the > > > Sun, > > > 150,000,000 kilometers multiplied by 2pi, and divided by one year. That > > > comes > > > out at about 0.0001c. > > > ============================================== > > > > so replace L0 by xi and replace L by x. > > > ================================================ > > > Nope. > > > replace L0 (which you cannot measure without stopping the Earth) with > > > x-vt. > > > > Lorentz claims L = L0 * sqrt(1 - v^2/c^2) > > > becomes x = xi *sqrt(1 - v^2/c^2) > > > ================================================ > > > Nope, L0 becomes x' = x-vt > > > and Lorentz claims x' = xi / sqrt(1 - v^2/c^2) > > > but Einstein claims xi = x' / sqrt (1-v^2/c^2) > > > > ie x=xi/beta (Einsteins beta = 1/sqrt(1 - v^2/c^2)) > > > > ================================================== > > > Nope, > > > xi = x' * beta. (Einstein's beta = 1/sqrt(1 - v^2/c^2), not sqrt(1 - > > > v^2/c^2) ) > > > > ie xi=beta x > > > > ================================================= > > > Not quite, xi = beta x', > > > where x' = x-vt > > > > OK, as this is Einstein's formula. > > > ============================= > > > Yep, but it isn't Lorentz's formula. > > > > You say that Einstein claims that L = L0 / sqrt(1 - v^2/c^2) > > > =============================================== > > > Yep. Here it is: > > >http://www.fourmilab.ch/etexts/einstein/specrel/www/figures/img53.gif > > > I don't claim what I can't quote. > > > > ie x = xi/sqrt(1 - v^2/c^2) > > > ie x= xi beta (Einsteins beta = 1/sqrt(1 - v^2/c^2)) > > > NOT OK, as this is not Einstein's formula. > > > ================================================= > > > True enough, x isn't x' = x-vt. > > > > Einstein's formula is xi=beta x > > > ==================================================== > > > Nope. > > > Einstein's formula is xi=beta x' > > > Here it is: > > >http://www.fourmilab.ch/etexts/einstein/specrel/www/figures/img53.gif > > > I don't claim what I can't quote. > > > > so you should not think that that Einstein says that L=L0 / sqrt(1 - > > > v^2/c^2). > > > ================================================= > > > Yes I should because he did say that. > > > > Or you should make it clear to me why you think that this is what > > > Einstein is saying. > > > =================================================== > > > I've been making it as clear as I can. > > > Perhaps this will help: > > >http://www.androcles01.pwp.blueyonder.co.uk/Smart/x'=x-vt.gif > > > "If we place x'=x-vt, it is clear that a point at rest in the system k > > > must > > > have a system of values x', y, z, independent of time." -- Einstein, > > > Section > > > 3.- Hide quoted text - > > > > - Show quoted text - > > > You mentioned aether wrt Lorentz. I don't know much about aether and > > don't want to go there, unless my arm is twisted. Not yet anyhow. > > Just giving you some history. Do as you like with it. > > > There doesn't seem to be much point in having frame k if we don't use > > it. We did not previously specify that the object being measured was > > at rest in frame k, but I was assuming it. > > See below. > > > Say L0 is a measurement of the length of a stationary object in the > > stationary frame K. Ie x=L0. > > Correct. > > > If you re-measure, in stationary frame K (t, x, y, z), the length of > > the object when the object is moving within frame K > > Look at this gif: > http://www.androcles01.pwp.blueyonder.co.uk/Wave/k_frame.gif > > First, the k-frame moves in x. The ball moves with it. > Second, the k-frame moves in y. > Third, the k-frame moves in z. > Fourth, the k-frame rotates about its origin. > The ball is fixed (at rest) in the k-frame, so it "moves in the K-frame", > but you cannot tell that it rotated because it has no features, or that > it rotates ABOUT THE ORIGIN of the k-frame. If I say "the ball rotates" > you might think I meant it rotates about its own axis, but it actually > rotates about the z-axis of the k-frame. > The frames are invisible mathematical entities, but they are essential to > the engineer in describing motion mathematically. The program I used to > create that gif is free, you can download it from > http://sketchup.google.com/ > and discover for yourself just how much the idea of frames is built into > graphics. > Nothing moves "within a frame". Instead, another frame moves relatively > to the former frame. > > > then the object > > will no longer have length L0 in frame K. Ie x <>L0. If the object > > is stationary within frame k and frame k itself is moving at speed v > > compared to frame K, the object can be measured in moving frame k > > (tau, xi, eta, zeta). Ie xi=L0. > > My gif doesn't change the ball size. > > > I earlier used Einstein's equations with t=0. You are bringing time > > into the explanations and its seems perhaps that you are going into a > > path where you want me to check Einstein's derivation of his > > equations. > > Oh yes, certainly I do. You'll never understand nonsense unless you > examine it. Get around to it. > > > I was intending to use his equations, not derive them. > > Big mistake. That's GIGO, garbage in, garbage out, and what every idiot > does. > > > But to be more general I will derive the required result for any time > > t. > > ================================================= > Not for me you won't, I'm not interested in going backwards over old > ground. > {SNIP} > Try to see the forest, you are looking at leaves on a tree. > You are getting tied up in knots fumbling with the algebra. > Nothing gets contracted, the k-frame gets expanded and Einstein was a bozo. Hi Androcles Thank you for the history and the pointer to the graphics software and for your logic so far. I think that I have shown that Einstein's equation xi = beta (x-vt) produces a contracted length (x=L) when used to calculate the length of a moving object. The moving object being at rest in frame k where its rest length is measured as xi=L0. E.g. x = 0.5 xi. (or L = 0.5 L0). x is in the frame K. xi is in moving frame k. (k moves at speed v within frame K .) If you disagree, as I think you do, then the discrepancy lies in our different understanding of the frames and the metrics in the frames? So the next question is what do we each understand by the frames? I accept your notion that all objects are to be measured at rest in a moving frame. (Noone can be sure their own frame is at rest absolutely. Saying that frame K is stationary is just a bad (but brief) way of saying that frame K is the frame that the narrator or observer or calculator is in. And I take your hint that is is poor wording.) That means that L0 is measured in moving frame k by an agent also at rest in that frame (eg a person on a train measuring the length of that train). The measurement will be xi=L0. L is the apparent length of the object in frame K containing a narrator/or/observer/or/calculator at rest in that frame. L is calculated as a value of x. As frame k is moving within frame K, the observer at rest in frame K cannot measure the length of the object, only calculate it. (I have been thinking about how to measure x rather than calculate it. If in frame K the observer took a photograph of the receding moving object, the light from the far end of the object would take longer to reach the observer than the light from the near end of the object. So the observed far end of the object must be at an earlier time when the object hadn't travelled as far. So the photo would lead to an underestimate of the calculated length x. But that is a digression.) Looking at the frames this way, I cannot see how you could get L = 2 * L0. And I cannot, yet, understand how you look at it that way.
From: waldofj on 14 May 2010 12:27 > I think that I have shown that Einstein's equation xi = beta (x-vt) > produces a contracted length (x=L) when used to calculate the length > of a moving object. The moving object being at rest in frame k where > its rest length is measured as xi=L0. E.g. x = 0.5 xi. (or L = 0.5 > L0). x is in the frame K. xi is in moving frame k. (k moves at speed v > within frame K .) > > If you disagree, as I think you do, then the discrepancy lies in our > different understanding of the frames and the metrics in the frames? no, he's just an idiot > So the next question is what do we each understand by the frames? don't confuse yourself. You already have it exactly right. > > I accept your notion that all objects are to be measured at rest in a > moving frame. (Noone can be sure their own frame is at rest > absolutely. Saying that frame K is stationary is just a bad (but > brief) way of saying that frame K is the frame that the narrator or > observer or calculator is in. And I take your hint that is is poor > wording.) That means that L0 is measured in moving frame k by an > agent also at rest in that frame (eg a person on a train measuring the > length of that train). The measurement will be xi=L0. > > L is the apparent length of the object in frame K containing a > narrator/or/observer/or/calculator at rest in that frame. L is > calculated as a value of x. As frame k is moving within frame K, the > observer at rest in frame K cannot measure the length of the object, > only calculate it. > > (I have been thinking about how to measure x rather than calculate it. > If in frame K the observer took a photograph of the receding moving > object, the light from the far end of the object would take longer to > reach the observer than the light from the near end of the object. So > the observed far end of the object must be at an earlier time when the > object hadn't travelled as far. So the photo would lead to an > underestimate of the calculated length x. But that is a digression.) here's another way to look at it put a ruler along the x axis (in system K) and place a BUNCH of cameras along the ruler, each one having a clock with it, and of course all the clocks are synced up. also assume the rod in system k has it's left end at the origin of k. As system k (and the rod) move past, at time t = 0 (when the origins of both systems coincide) all the cameras take a picture. One of them will be close enough to the far end of the rod to see how it aligns with the ruler, and there's your measurement. The reason I say each camera has its own clock is to make easier to see how this looks from k's POV. From k's POV the clocks in K are not synced. Look at the LTE for t t = (tau + vxi/c^2)beta when tau = 0 only the clock in K that aligns with the origin (xi = 0) will read t = 0 all the clocks in the forward direction read t > 0, specifically t = (vxi/c^2)beta. The result of this is that from k's POV all those pictures are not being taken at the same time but rather at different times like a ripple effect. More to the point, since all the cameras are taking their picture when their local clock reads t = 0, all these pictures are being taken while tau < 0, so all the pictures are being taken too soon, the rod is not in the correct position yet. The conclusion is from K's POV the rod will appear shorter then it is in k. This effect is called the relativity of simultaneity and is definitely one of the screwier things to come out of relativity theory. > > Looking at the frames this way, I cannot see how you could get L = 2 * > L0. > > And I cannot, yet, understand how you look at it that way. nor can anyone else
From: Androcles on 14 May 2010 12:43
"waldofj" <waldofj(a)verizon.net> wrote in message news:51ba31b8-437c-471f-8d24-26b8c4c0cf25(a)m21g2000vbr.googlegroups.com... > I think that I have shown that Einstein's equation xi = beta (x-vt) > produces a contracted length (x=L) when used to calculate the length > of a moving object. The moving object being at rest in frame k where > its rest length is measured as xi=L0. E.g. x = 0.5 xi. (or L = 0.5 > L0). x is in the frame K. xi is in moving frame k. (k moves at speed v > within frame K .) > > If you disagree, as I think you do, then the discrepancy lies in our > different understanding of the frames and the metrics in the frames? no, he's just an idiot =================== Pity you can't back that up with logical debate, but then, you are just a snipping fuckwit and a bigot. |