Properties of a preferred frame, an inertial frame in SR and
in [Relativity]
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From: eric gisse on 21 Jul 2010 20:42 colp wrote: [...] > The phrase "and fail to confront the startling ideas of special > relativity" should read "and reject the internal contradictions > inherent in special relativity" How can someone who doesn't understand classical mechanics find 'contradictions' in SR? [...]
From: PD on 21 Jul 2010 23:20 On Jul 21, 6:28 pm, colp <c...(a)solder.ath.cx> wrote: > On Jul 22, 9:31 am, Sam Wormley <sworml...(a)gmail.com> wrote: > > > > > > > On 7/21/10 10:52 AM, JT wrote: > > > > No SR can not deal with multiple simultaneous observations of > > > different objects, it breaks down. I proved it in a thread recently > > > discussing with Sam and PD. They were unable to plot the position of > > > third object. > > > What's this bullshit, JT? > > > You need to read this: > > > Student understanding of time in special relativity: simultaneity > > and reference frames > > > Rachel E. Scherr, Peter S. Shaffer, and Stamatis Vokos > > Department of Physics, University of Washington, Seattle, WA > > > This article reports on an investigation of student understanding > > of the concept of time in special relativity. A series of research > > tasks are discussed that illustrate, step-by-step, how student > > reasoning of fundamental concepts of relativity was probed. The > > results indicate that after standard instruction students at all > > academic levels have serious difficulties with the relativity of > > simultaneity and with the role of observers in inertial reference > > frames. Evidence is presented that suggests many students construct > > a conceptual framework in which the ideas of absolute simultaneity > > and the relativity of simultaneity harmoniously co-exist. > > > See:http://arxiv.org/pdf/physics/0207109 > > > VII. CONCLUSION > > > "This investigation has identified widespread difficulties that > > students have with the definition of the time of an event and the > > role of intelligent observers. After instruction, more than 2/3 of > > physics undergraduates and 1/3 of graduate students in physics are > > unable to apply the construct of a reference frame in determining > > whether or not two events are simultaneous. Many students interpret > > the phrase relativity of simultaneity as implying that the > > simultaneity of events is determined by an observer on the basis of > > the reception of light signals. They often attribute the relativity > > of simultaneity to the difference in signal travel time for different > > observers. In this way, they reconcile statements of the relativity > > of simultaneity with a belief in absolute simultaneity and fail to > > confront the startling ideas of special relativity". > > The phrase "and fail to confront the startling ideas of special > relativity" should read "and reject the internal contradictions > inherent in special relativity" > > The internal contradiction regarding simultaneity can be traced back > to Einstein's "Electrodynamics of Moving Bodies", in which he asserts > that mechanics & optics have no properties relating to an absolute > frame of reference, and then contradicts this in his example of time > dilation by referring to a stationary frame and a moving frame. Are you taking "stationary frame" to mean "absolutely stationary frame" and "moving frame" to mean "absolutely moving frame"? Why? > > If Einstein were to have described his example of time dilation in > terms consistent with his principle of relativity (i.e. no absolute > frame), then the clock paradox would be immediately apparent.- Hide quoted text - > > - Show quoted text -
From: harald on 22 Jul 2010 05:18 On Jul 21, 9:45 pm, kenseto <kens...(a)erinet.com> wrote: > On Jul 21, 3:13 pm, PD <thedraperfam...(a)gmail.com> wrote: > > > On Jul 21, 1:59 pm, kenseto <kens...(a)erinet.com> wrote: > > > > No idiot....the top of a building have a different > > > state of absolute motion than the ground floor. > > > > Ken Seto > > > Ken, you've said in the past that relative motion is the difference > > between two absolute motion vectors. So if there is a difference in > > absolute motion between the top and the ground floor, then there would > > have to be nonzero relative motion between top and ground floor. Are > > the top and bottom of a building in relative motion? > > I said that relative motion between two objects A and B is the vector > components difference of their absolute motion along the line joining > them. This means that the vector components difference of A and B of a > building at the vertical direction is zero. But it does not mean that > A and B have the same state of absolute motion in the aether. Actually that is quite correct: even in the ECI frame the relative velocity of the top floor of a building and the cellar is non-zero. Now, those velocities are *nearly* the same, but that isn't important. You wrote: "Different gravitational potential means different states of absolute motion." The gravitational potential is independent of the rotation of the Earth. One could put two clocks at the North pole on different floors of a building in EQUAL inertial motion. As a result, with the stationary ether model they are ALSO in equal "absolute" motion BUT at a different gravitational potential. Harald
From: kenseto on 22 Jul 2010 08:32 On Jul 22, 5:18 am, harald <h...(a)swissonline.ch> wrote: > On Jul 21, 9:45 pm, kenseto <kens...(a)erinet.com> wrote: > > > > > > > On Jul 21, 3:13 pm, PD <thedraperfam...(a)gmail.com> wrote: > > > > On Jul 21, 1:59 pm, kenseto <kens...(a)erinet.com> wrote: > > > > > No idiot....the top of a building have a different > > > > state of absolute motion than the ground floor. > > > > > Ken Seto > > > > Ken, you've said in the past that relative motion is the difference > > > between two absolute motion vectors. So if there is a difference in > > > absolute motion between the top and the ground floor, then there would > > > have to be nonzero relative motion between top and ground floor. Are > > > the top and bottom of a building in relative motion? > > > I said that relative motion between two objects A and B is the vector > > components difference of their absolute motion along the line joining > > them. This means that the vector components difference of A and B of a > > building at the vertical direction is zero. But it does not mean that > > A and B have the same state of absolute motion in the aether. > > Actually that is quite correct: even in the ECI frame the relative > velocity of the top floor of a building and the cellar is non-zero. > Now, those velocities are *nearly* the same, but that isn't important. > > You wrote: > > "Different gravitational potential means different states of absolute > motion." > > The gravitational potential is independent of the rotation of the > Earth. One could put two clocks at the North pole on different floors > of a building in EQUAL inertial motion. As a result, with the > stationary ether model they are ALSO in equal "absolute" motion BUT at > a different gravitational potential. We are talking about absolute motion and absolute motion is that motion of an object wrt light. When the source and the detector shows frequency shift that means that there is a difference of absolute motions between them. In the same gravitational potential there is no frequency shift between the source and the detector and thus there is no difference in the states of absolute motion between the source and the detector. > > Harald- Hide quoted text - > > - Show quoted text -
From: kenseto on 22 Jul 2010 08:41
On Jul 21, 3:53 pm, PD <thedraperfam...(a)gmail.com> wrote: > On Jul 21, 2:45 pm, kenseto <kens...(a)erinet.com> wrote: > > > > > > > On Jul 21, 3:13 pm, PD <thedraperfam...(a)gmail.com> wrote: > > > > On Jul 21, 1:59 pm, kenseto <kens...(a)erinet.com> wrote: > > > > > No idiot....the top of a building have a different state of absolute > > > > motion than the ground floor. > > > > > Ken Seto > > > > Ken, you've said in the past that relative motion is the difference > > > between two absolute motion vectors. So if there is a difference in > > > absolute motion between the top and the ground floor, then there would > > > have to be nonzero relative motion between top and ground floor. Are > > > the top and bottom of a building in relative motion? > > > I said that relative motion between two objects A and B is the vector > > components difference of their absolute motion along the line joining > > them. This means that the vector components difference of A and B of a > > building at the vertical direction is zero. But it does not mean that > > A and B have the same state of absolute motion in the aether. > > Which means that the difference in the absolute motion has to be > solely in the horizontal direction. Otherwise, a vertical component of > the difference would appear. No, NO, NO.... We are talking about absolute motion and absolute motion is that motion of an object wrt light. When the source and the detector shows frequency shift that means that there is a difference of absolute motions between them. Since there is a frequency shift in the vertical direction and thus there is a difference in the states of absolute motion between the source and the detector. In the same gravitational potential (on the surface of the earth) there is no frequency shift between the source and the detector and thus there is no difference in the states of absolute motion between the source and the detector. Ken Seto > > Now that we've established that the difference in the absolute motion > is wholly horizontal, it is worth noting that there are two orthogonal > directions in the horizontal plane, and you can always choose > coordinates in a plane such that a horizontal vector has zero > magnitude in one horizontal direction and nonzero magnitude in the > other horizontal direction. > > PD- Hide quoted text - > > - Show quoted text - |