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I was enjoying Zee's book on GR when I noticed the location of this "a(t)" thing in the metric sound quite disturbing to me.

BTW: I experience the same annoyance and went down to the same conclusions, when I watched a related Theoretical Minimum lesson...

Here's the setup, the flat Minkowsky spacetime (with the c=1 convention):

Here's the disturbing variation, a metric with "a scale factor":

now:can you see "where" that "a(t)" is, in the equation, and what also there should be nearby, when dropping the c=1 convention?

so:is it just me, or a(t) is just the inverse of the speed of light, changing in time?

This view would be consistent with what those people are saying, right?

Let alone: I'm not reading the equations wrong, am I?it's really what the equations say

PS: That's just using Susskind's "math autopilot", isn't it?

Cheers

Corrado.

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# I Where the scale factor a(t) appears in the metric

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