Talk:Special relativity/Archive 2

message: While looking for featured picture, I found a page  with scan of orginal Einstein notes on the subject. They are from 1918-1919, but the picture  has a copyright notice, so I am not sure if we can use it after all. --Piotr Konieczny aka Prokonsul Piotrus 19:12, 10 Dec 2004 (UTC)
replies: text: At least under United States copyright law, the copyright claim is invalid.  The creator of that photograph was trying to make an accurate copy of another work.  There is no creative input involved, and so no copyright applies beyond that of the original work. --Carnildo 22:16, 13 Dec 2004 (UTC)
thread_title:  Picture 

message: Excuse me for butting in here. I don't mean to disturb your discussion, but I'm wondering whether Cadwgan's views count as "original research" (i.e. uses unpublished data or analysis, or is a novel narrative, interpretation or new synthesis of published information), because if it is, it's not allowed in Wikipedia, even if it's true. My problem is that I don't know enough about SP to judge whether these views count as "original research" or not. Cadwgan, have your views been published in a peer-reviewed journal? If so, can you provide a reference?  Slim 04:15, Dec 15, 2004 (UTC)
:My understanding of Cadwgan's view is that
:#The second postulate can only be experimentally verified by measuring the one-way speed of light using two synchronized clocks in the same reference frame.
:#These clocks cannot be synchronized in their final locations using light, as the speed of light is what is being measured.
:#These clocks cannot be synchronized in their final locations, as there will be a propogation delay in the synchronization.
:#These clocks cannot be synchronized before being moved into location for the experiment, since any movement will create relativistic effects that will de-synchronize the clocks.
::Thus, the second postulate cannot be proven.
:--Carnildo 06:49, 15 Dec 2004 (UTC)
replies: text: My point is that, whether Cadwgan is saying A, B, C or whether he's saying X, Y, Z, if what he's saying has been published in a peer-reviewed journal or book, then it can be used. If it hasn't, it can't be. Those are the Wikipedia rules. See Wikipedia:No original research. And references must be provided by the people who have written this article, and by Cadwgan if he wants to add anything. Slim 07:42, Dec 15, 2004 (UTC)
My counterclaim is that the second postulate has not been experimentally verified, i.e., that no one has ever shown that light's one-way speed between two same-frame clocks is invariant or isotropic; and I can easily back up this view of the postulate with a peer-reviewed paper from Einstein himself, as follows:
[quoting Einstein from his 1905 relativity paper]  
 "In agreement with experience we further assume the quantity 
                       2AB/(t'a-ta) = c
 to be a universal constant - the velocity of light in empty space."
       http://www.fourmilab.ch/etexts/einstein/specrel/www/
This brief Einsteinian statement proves that Einstein did not postulate at all regarding light's one-clock, round-trip speed; instead, he merely accepted round-trip invariance and isotropy as experimental ("In agreement with experience") facts, which, we can all agree, they practically were even in 1887. (However, Einstein was forced to use the word "assume" because the 1887 experiment did not actually cover invariance, but covered only isotropy, but of course invariance was a very safe assumption.)
[again quoting Einstein from his 1905 relativity paper]  
 "1. Any ray of light moves in the 'stationary' system of coordinates 
 with the determined velocity c, whether the ray be emitted by a stationary 
 or by a moving body. Hence 
                  velocity = light path/time interval
 where time interval is to be taken in the sense of the definition in §1."
Note Einstein's use of coordinate systems. These systems consist of rulers and clocks; therefore, Einstein was talking about light's one-way speed per two clocks in the same frame. (He did not use slow clock transport.)
Furthermore, as I have already pointed out, Einstein himself declared mathematically that under certain circumstances light's one-way, two-clock speed could be c - v. It has been falsely claimed that this was taken out of context, but here is my simple proof to the contrary: 
Despite any and all of the words of Einstein preceding or following his presentation of the simple equation w = c - v, Einstein did in fact derive that equation; all I ask of those who "yell" Out of context! is that they simply show us Einstein's derivation.
Moreover, there is a peer-reviewed 1992 paper which shows that light's one-way, two-same-frame-clock speed need not be invariant or isotropic. Here is the citation:
Elementary relativity with 'everyday' clock synchronization
C Leubner, K Aufinger and P Krumm 1992 Eur. J. Phys. 13 170-177
Finally, I wish to know if anyone, anywhere really believes that Einstein's second postulate does not pertain to light's one-way speed between two same-frame clocks. It should be clear to anyone that this is at least a major part of the Wiki claim, and it is my counterclaim that this measurement has yet to be made. (And the very fact that it has not been made, not even on paper, tells anyone who will listen that it cannot be made.) Cadwgan Gedrych 14:16, 15 Dec 2004 (UTC)
thread_title: No original research