On 2015-01-26, David Woolley <[email protected]> wrote: > On 26/01/15 17:11, William Unruh wrote: >>> physical principle ( the frequency of oscillation of a cesium atom in a > XXXXXXXXXXXXXX >>> >certain transition) and the rotation of the earth. It used to be defined >> ^not >>> > > > It's a quantum spin flip. There is no physical oscillation. Not that > that really changes anything about UTC or TAI.
Tell that to the electromagnetic wave that comes out of the atom. The energy of that spin flip corresponds directly to a frequency via Planck's constant. And yes, an actual frequency of oscillation of the EM field. _______________________________________________ questions mailing list [email protected] http://lists.ntp.org/listinfo/questions
