Disputatio:Relativitas generalis

semi-protecta[fontem recensere]

Some anonymous user keeps putting a link on the page advertising some bizarre physics discussion forum. The link is written in bad englsih and as far as I can tell the page advertised is completely without merit and furthermore not even in latin. So I put semiprotecta on it.--Rafaelgarcia 06:18, 17 Iunii 2007 (UTC)[reply]

The current need for this seems to have been eliminated, am I right, Rafael?--Ioscius ^(disp) 17:01, 2 Februarii 2008 (UTC)[reply]

Curvatio[fontem recensere]

You have a source for this, Rafael? I would have thought flexio...--Ioscius ^(disp) 17:01, 2 Februarii 2008 (UTC)[reply]

Words gives the following possibilities for curvature:

curvamen, curvaminis  N (3rd) N     3 2  N   [XSXCO]  
curvature, curve/bend, bending; curved form/outline; arc (of the sky); vaulting;

curvatio, curvationis  N (3rd) F     3 1  F   [XSXEO]  
curvature; bend;

curvor, curvoris  N (3rd) M     3 1  M   [XSXFO]  
curvature; crookedness (L+S);

whereas looking up flexio it gives:

io                   SUFFIX                             
-ing, -ion, -ery; indicates the action or result of the action of the verb;
flexio               N      3 1 NOM S F                 
flexio               N      3 1 NOM S F                 
flexio               N      3 1 VOC S F                 
flexio               N      3 1 VOC S F                 
flecto, flectere, flexi, flexus  V (3rd)   [XXXBX]  
bend, curve, bow; turn, curl; persuade, prevail on, soften;

so that flexio would best translate "bending" and "curvatio" would most directly translate "curvature" with the fewest additional connotations. It would be good to see what Gauss called curvature.--Rafaelgarcia 17:18, 2 Februarii 2008 (UTC)[reply]

Here's a new one: Principia mathematica--Newton uses "curvatura" to mean curvature! I guess we should bow to Newton on this...--Rafaelgarcia 17:40, 2 Februarii 2008 (UTC)[reply]

Thanks for clarification, Rafael.--Ioscius ^(disp) 15:48, 3 Februarii 2008 (UTC)[reply]

Remember that the English structure that most closely matches Latin words in -tio is that of the English gerund; so flexio is 'a bending', and curvatio is 'a curving', and disputatio is 'an arguing', and so on. Of course that's just a basic point, and individual nouns developed particular connotations. ¶ If Newton used it, surely Vicipaedia can, especially in the fields of mathematics & physics. IacobusAmor 17:58, 2 Februarii 2008 (UTC)[reply]

Conventions[fontem recensere]

I have never found the time-component of a quadrivector in the fourth position, I think it should be placed in the first. Moreover the signature (1,-1,-1,-1) is nowadays more frequent and recommended than (-1,1,1,1).--Maxos 23:04, 22 Februarii 2008 (UTC)[reply]

It is Einstein's original convention, which is actually most natural. Look at his books and papers.Besides there are about 4 different conventions out there. This one emphasizes the continuity between SR and GR.--Rafaelgarcia 23:42, 22 Februarii 2008 (UTC)[reply]

Also nowadays the convention is to avoid tensor component notation altogether, as is evident in the other wikipedias, but this is actually harder to grasp for the general reader and succeeds only in making the subject inaccessible to the general reader.--Rafaelgarcia 23:46, 22 Februarii 2008 (UTC)[reply]

Given that we are the single wikipedia that values old things, can't we make allowance, within reason, for a simple convention that Einstein himself used? And which also makes the subject acessible to a general reader?--Rafaelgarcia 23:47, 22 Februarii 2008 (UTC)[reply]

After all haven't you heard of time being the 4th dimension?--Rafaelgarcia 23:50, 22 Februarii 2008 (UTC)[reply]

Well, obviously it is only a matter of convention, stars do not know tensor analysis; I would simply follow the standard of the texts we read everyday just for accessibility's sake, anyway your point is acceptable.--Maxos 07:22, 23 Februarii 2008 (UTC)[reply]