Misplaced Pages

This is an old revision of this page, as edited by Ems57fcva (talk | contribs) at 19:09, 2 June 2005 (Clean-up tag). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

A pedantic quibble: the author of this article says that

${\displaystyle U(x,t)=f(kx+ct)+g(kx-ct)}$

is the wave equation. But of course this is the D'Alembert general solution to the one-dimensional wave equation, not the equation itself, is often written in coordinate-free notation as

${\displaystyle \Box U=0}$

(where ${\displaystyle \Box }$ is the Laplace/Beltrami operator) or in conventional PDE notation (using a Cartesian coordinate chart) as

${\displaystyle U_{tt}=U_{xx}}$

I propose to modify this page to correct this, if no-one objects.

Clean-up tag

Would someone mind explaining how this article needs to be cleaned up? Other than an extraneous paragraph (which I have removed), I see nothing wrong with the structure of this article. I wonder if a wave equation is the right example myself, but I will leave it up to Hillman's judgement as to what to do with that.

It is my opinion that this article is of the right size and structure, being a coherent explanation of general covariance and a simple example. I think that the best way of cleaning it up is to drop the needs-cleaning-up tag.

--EMS | Talk 19:09, 2 Jun 2005 (UTC)