Talk:General Relativity/Introduction

DavidCary's formula is wrong:

$$ds^2 = dz^2 + (2 r \sin\frac{\theta}{2})^2$$

If this is for a cylinder, with the standard definitions of z, r, &theta;, then the metric is:

$$ds^2 = dz^2 + r^2 d\theta^2$$

The cylinder is intrinsically flat. Hmm, this has to be reorganised - the cylinder is flat like the plane. The sphere is different. i'm rewording a bit.

i'm removing: The full formula for arbitrary (r, &phi;, &theta;) will be worked out later. because we are interested primarily in differentials. i don't see any point in distracting the reader by talking about path integrals at this point... Boud 12:38, 12 January 2006 (UTC)

GR
Why this abbreviation at the start of the article when you don't use it?