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The Poincare-AdS$_3$ geometry is given in the Wikipedia article on Anti-de Sitter space as

$$ds^{2} = \frac{dr^{2}}{r^{2}} + r^{2}g_{\alpha\beta}dx^{\alpha}dx^{\beta}$$

$$=\frac{dr^{2}}{r^{2}} + r^{2}(-dt^{2} + dx^{2}),$$

where $(t,x)$ are the coordinates on the boundary of the cylinder. Therefore, using $x = r \theta$, we find that

$$ds^{2} = \frac{dr^{2}}{r^{2}} - r^{2}dt^{2} + r^{4}d\theta^{2}.$$

But I am not able to make a consistent dimensional analysis. For example, $dr^{2}/r^{2}$ is dimensionless, but $r^{2}dt^{2}$ has a mass dimension of $-4$ and $r^{4}d\theta^{2}$ also has a mass dimension of $-4$.

What am I doing wrong here?

nightmarish
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