4 ms·
But one meter is still the length we are used to. So we got the resonant frequency of some atoms, which is arbitrary because they just happened to be relativel
by Double_a_92 8y ago
But one meter is still the length we are used to.
So we got the resonant frequency of some atoms, which is arbitrary because they just happened to be relatively easy to measure for us... Multiplied by some arbitrary factor so the unit reaches the usual length.
That doesn't seem very fundamental to me. Could you imagine proposing that to some intergalactical economic union as new standard?
- ElBarto 8y agoThe resonant frequency of the atom is not arbitrary, it is a physical constant. That's the key and the point: It allows to measure exactly 1 second anywhere in the universe because the resonant frequency of that atom is the same anywhere in the universe. Compare with a previous definition of the second as a fraction of the solar day... A solar day isn't in fact constant and, in any case, once you leave earth it means nothing at all.