All real signals have limited bandwidth, including noise.
Assuming there's no external source of radiation, I can absolutely guarantee there is no energy propagating at cosmic ray frequencies in a circuit built around an audio op-amp with standard off-the-shelf components.
No lowpass filter or circuit attentuates any frequency to zero, including your example. The attentuation will be 10^(-huge number), but it wont be zero.
This isn't just pedanticism, you really can't just sample at 2x the corner frequency of your circuit.
(Unless there's some quantum effect that gives a minimum energy level possible for a signal? But even then it would be probabablistic? Is this what you mean? I didn't pay close enough attention in physics class)
Assuming there's no external source of radiation, I can absolutely guarantee there is no energy propagating at cosmic ray frequencies in a circuit built around an audio op-amp with standard off-the-shelf components.