User talk:Robinhw

Welcome!

Hello, Robinhw, and welcome to Wikipedia! Thank you for your contributions. I hope you like the place and decide to stay. Here are a few good links for newcomers:

I hope you enjoy editing here and being a Wikipedian! Please sign your name on talk pages using four tildes (~~~~); this will automatically produce your name and the date. If you need help, check out Wikipedia:Where to ask a question, ask me on my talk page, or place {{helpme}} on your talk page and someone will show up shortly to answer your questions. Again, welcome! -Ambuj Saxena (talk) 11:00, 9 March 2006 (UTC)[reply]

Thanks.

Thanks for creating Modern Gnosticism to give Ndru01 a place to put his text. It was an expeditious solution. Alienus 03:23, 5 April 2006 (UTC)[reply]

Thanks for your comment on the main page

It gave me an idea. NinaEliza (talk • contribs • count • logs • email) 19:24, 15 December 2006 (UTC)[reply]

Re: Removal of merger notice

Usually the merger notice is used to notify editors that a similar article exitst that they may not know about. It happens often that someone creates an article oin wikipedia not knowing that another similar article with a different title already exist. If that new article is very good so that you don't want to just delete it, then it is useful to notify editors of both article about the other article. But almost all the editors of the special relaivity article know about the existence of the intro article and vice versa, so this issue could be raised on the talk page.

However, in the case of the intro to relativity article, the fact that it has become a bit similar to the main relativity article is actually not a desirable thing at all. The purpose of that article was to have an article that is more accessible to lay people. I think that editors there have complained about this. The merger notice was perhaps sort of an independent confirmation that there indeed exists a problem. :) Count Iblis 13:28, 1 October 2007 (UTC)[reply]

Thanks -- and "The Chain of Now"

Thanks for your comment.

I agree that causality is essential to the argument about the limit, v < c. Another thing I have noticed, but cannot reference in external reliable sources (I do not have Rindler's text at hand), is the following proposition, which seems somehow related to causality: "Given two arbitrary points (events), say A, and Z, in a connected region of spacetime S, it is possible to construct a (typically but not necessarily finite) sequence of points, say B,C,...,Y, all in S, such that the points in the sequence are all pairwise "simultaneous", where by "simultaneous" I mean that each adjacent pair of events in the chain has a spacelike separation (or, there exists a Lorentz frame in which those two events are simultaneous). That is, any two points in the spacetime can be connected by a chain ("The Chain of Now"?) of other points which are pairwise "simultaneous".

I think this proposition is true, and probably well known (or intuitively obvious) to many physicists, but I am not quite certain it is correct, and if so where it is stated in the literature. I am also very uncertain about what it means in the context of my understanding of causality, and wonder if and where that has been discussed. It is obvious I think that the crux of the matter is that simultaneity is transitive (ie, "A simultaneous to B", and "B simultaneous to C", imply "A simultaneous to C") in Newtonian physics, but not in Relativity. In our folk wisdom we seem to say that the past is gone, the future is "pie in the sky", and the present is "real". But I get a queasy feeling about all this obvious stuff in the light of the forgoing considerations.

At the moment (in my ignorance) this is all OR, but if it were not, it seems it might find a place in an article somewhere. Cheers, Bill Wwheaton (talk) 19:18, 28 October 2008 (UTC)[reply]