Atomic Clock Comparisons as Bounds on Fundamental Decoherence: A Computed Conversion

This paper converts the fractional frequency stability of optical atomic clocks into an upper bound on any fundamental decoherence rate affecting the clock transition. For a strontium-like transition at 4.29e+14 hertz with fractional instability 1.00e-18, the bound is 2.695e-03 per second. A representative Planck-suppressed rate evaluated for comparison is 6.934e-19 per second, a factor 3.887e+15 below the clock bound. Clocks are therefore excellent bounds on decoherence that couples directly to internal energy splittings at observable strength, but they do not reach Planck-suppressed rates in the simple linear suppression model. The study is simulated and computed from stated assumptions; it is not a measurement.