The FRW metric at the origin ##r=0##, with ##c=1##, is given by:(adsbygoogle = window.adsbygoogle || []).push({});

$$ds^2=-dt^2+a(t)^2dr^2$$

Now one can change variables so that near the origin the FRW metric is approximated by the Minkowski metric describing flat spacetime:

$$dS^2=-dT^2+dR^2$$

where:

$$dT=\frac{dt}{a(t)}$$

$$dS=\frac{ds}{a(t)}$$

$$dR=dr$$

All the physics experiments that we perform locally are assumed to occur in flat spacetime as described above.

Surely therefore our locally measured time is not the cosmological time ##t## but rather the conformal time ##T## ?

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# Is our locally measured time actually conformal time?

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