(adsbygoogle = window.adsbygoogle || []).push({}); Question regarding GR and the "cylinder condition"

Im reading that in Kaluza-Klein theory, the derivatives (of the metric [tex] g_{\mu\nu}[/tex] with respect to the 5th dimension, [tex] X^4 [/tex], were chosen to be zero, to explain why we do not "feel", or detect, the existence of [tex] X^4 [/tex] i.e. the Cylinder Condition (a few different sources including http://arxiv.org/abs/gr-qc/9805018 page 4, 1st paragraph.

But thinking about minkowski space it seems to me that derivatives of the minkowski metric with respect to all the spatial coordinates [tex] X^1, X^2, X^3 [/tex] are zero, but obviously we do detect [tex] X^1, X^2, X^3 [/tex], thus my confusion.

I realize that zero derivatives implies that the geodesic becomes an equation that describes flat space. But not why it would mean that we don't detect those dimensions.

Thanks.

B

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# Homework Help: Question regarding GR and the cylinder condition

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