I think this analysis is great and I like it a lot, but it's not quite what I was going for. Here, the size of a cell works against an independent measurement o

I think this analysis is great and I like it a lot, but it's not quite what I was going for. Here, the size of a cell works against an independent measurement of length like "one meter". But, at a much more fundamental level, I kind of meant why is a meter a meter? If everything in the universe doubled in length overnight, how would we know since our meter sticks would double, too, which admits two possibilities: 1) If lengths are absolutely fixed, why are they fixed at that scale? Why *didn't* things end up doubled (assuming an external absolute to measure against). 2) If they're *not* absolutely fixed, the "fundamental length" appears pretty fixed to us as humans because things kind of look the same day-to-day. Is there a variation we just don't perceive? Is the fixedness we see just us imposing part of our perception on the world? It's sort of like this illustration of gauge fixing[1] -- just like "how do you know the cylinder is twisted?", you can ask "how do you know your fundamental lengths?" [1]: https://en.wikipedia.org/wiki/Gauge_fixing#An_illustration https://en.wikipedia.org/wiki/Gauge_fixing#An_illustration