Talk:Twin paradox/Archive 5

message: I move the following addition by Moroder here for discussion:
There was never any confusion on this subject. For example in his 1934 edition of "Relativity, Thermodynamics and Cosmology", prof. R.C. Tolman was noticing (page 27) that while "a constant velocity in system S' implies a constant velocity in system S, it is interesting to note that a constant acceleration wrt system S' , would not in general imply a constant acceleration in system S". In other words, there was never any confusion relative to the absolute nature of acceleration.
That there was confusion on that subject is well established by a number of sources, one of which is referenced in the article and another well known expert in this field claims the same, as cited above. Leaving that aside, the Tolman citation plus accompanying remark does not clarify much and the "in other words" does not seem to match the cited contents; this risks to instead confuse the readers. Harald88 12:57, 26 November 2006 (UTC)
replies: text: What article, harry? The crank paper of Unnikrishnan that you keep plastering everywhere, whether it fits or not? Do you understand the mistakes in the "paper" that you keep inserting? Have you read it? Can you follow it? Moroder 16:18, 26 November 2006 (UTC)
thread_title:  unclear addition by Moroder 

message: [I move this from my Talk page. Note: I asked Moroder to put discussions on the corresponding Talk pages; I also informed him/her that I won't respond to "harry" and instead will delete wrongly addressed comments -- here I make a one-time exception, and move it to this page instead of just deleting it.] Harald88 18:50, 27 November 2006 (UTC)
thread_title:  Twisting the Twins 

message: —Preceding unsigned comment added by 12.30.216.138 (talk • contribs) 14:42, November 30, 2006
: See this diff.  In a nutshell, Harald88 is upset over my removal of the last half of the "Resolution in general relativity" section, including the removal of the Unnikrishnan reference.  I will therefore propose that it be removed if noone other then Harald objects to that.  (Let's give this a few days and see if anyone has anything to say about it.) --EMS | Talk 03:04, 1 December 2006 (UTC)
replies: text:  I've reproduced (in italics) the deleted paragraphs below for reference. The first paragraph is not clear and therefore difficult to evaluate as to content. Personally I am not totally convinced by the alleged solutions using SR. Although I have yet to carefully read the SR solutions in the article, from my previous studies and presumption as to the article's content, I am not sure about their validity. E.g., when using the frame jumping method, is the behavior of the traveler's clock adequately analyzed at the instantaneous turnaround, or is this issue swept under the rug? ... Concerning the critique below of Einstein's GR solution, I am not sure I understand the claim that using the equivalence principle requires the assumption of an instantaneous propagation of the gravity field to the stationary twin. Whether one uses SR or GR, one always calculates based on local observations, and then applying the principles and transformation equations of the theory being used. Otoh, for there to be a real difference in clock readings, we must be dealing with bonafide differences in gravity fields. In this view, Builder's critique would seem to have merit. ... In sum, I think this entire issue needs to be thought through with much care before we leave the GR section trucated. green 12.30.216.138 04:20, 1 December 2006 (UTC)

text: I see that the neutrality issues have not been corrected but the banner has been removed. Please don't remove the banner without addressing these issues, thanks! Harald88 22:41, 5 December 2006 (UTC)
thread_title: Why is neutrality of article being challenged?

message: The twin paradox has to faces: 1.Twins are no longer of same age. Today, this is no longer a problem, we generally accept, that time is  not an absolute physical item.
2.The misunderstanding of symmetry: Movement is relative. Two object independently determine the change of their distance over time and determine the same velocity. It is not evident that both measure (compute the relation of changing in space distance and the time distance) the same value for this velocity! But when exchanging this value (for example, with a light signal), they both can independently see, that they measured the same value of speed for the relativ motion. To now, they don't know, if their "aging" is different. The paradox arises from the "fact", that according to special relativity both can "see" the other one moving and "know", that the other ones time is dilated. When they meet, one is older, one is younger. So, what happens, if both can not only exchange information about speed of relative moving, but also speed of their own time? How do we measure time? In principle by counting events, that are obviously periodical. For example by generating electromagnetic radiation with help of certain atoms. We believe, that the behaviour of atoms defines time. So, what happens, if the twins agree before they start, to exchange the value of relative velocity by sending a pulse width modulated signal of a certain light atomic source, where the pulse width reflects the relation of relative velocity to independently in place determined velocity of light. When they receive the signals, they receive two informations: 1. PWM represents relative speed. 2. The relation of frequency (or wavelength) of the received message and the sended message. This later is a measure for the "time" speed. The question is: will they both get the same value or not. ErNa 09:08, 1 December 2006 (UTC)
thread_title:  What is this discussion about