Talk:Nambu–Goto action

Whew!

I just expanded this article beyond stub status. I can forsee a few things which should be done next, in addition to proofing the material I just put in:

• writing the Nambu-Goto action in terms of an induced metric
• reparametrization invariance
• quantizing the action (at least an outline of the procedure)

—Anville 18:47, 21 Sep 2004 (UTC)

"Derivation"?

I think the heading "Derivation" is inappropriate. In particular, the body of text which follow this heading has very little to do with either the derivation of the action from first principles or the derivation of the Nambu-Goto equations of motion. I propose that the heading either be changed to something more appropriate or that someone actually treats the derivation in full, preferably from the point of view of the induced metric on the world-sheet.

I also think more could be done to mention appropriate limits of the variation and the boundary conditions imposed on the equations of motion. If I can find time I'll do this over the coming days.--St Cyrill 16:45, 10 February 2006 (UTC)

"2d Minkwski metric?"

It says "..where $\eta _{\mu \nu }=\mathrm {diag} (-1,1)$ is the two-dimensional Minkowski metric" but I dont think so. The induced metric should be the pull-back of the space-time metric by the embedding $X^{\mu }:\mathrm {Worldsheet} \rightarrow \mathrm {Space-Time}$ so it should be the D-dimensional metric, or am I wrong? (J.) —Preceding unsigned comment added by 78.53.8.101 (talk) 11:31, 1 February 2010 (UTC)

Yes, I think that there is a problem, but I am not sure how to fix it. JRSpriggs (talk) 02:42, 2 February 2010 (UTC)