The understanding of the origin of $1/f$ magnetic flux noise commonlyobserved in superconducting devices such as SQUIDS and qubits is still a majorunsolved puzzle. Here we discuss the possibility that a significant part of theobserved low-frequency flux noise measured in these devices is ultimatelyseeded by cosmological fluctuations. We consider a theory where a primordialflux noise field left over in unchanged form from an early inflationary orquantum gravity epoch of the universe intrinsically influences the phasedifference in SQUIDs and qubits. The perturbation seeds generated by this fieldcan explain in a quantitatively correct way the form and amplitude of measuredlow-frequency flux noise spectra in SQUID devices if one takes as a source offluctuations the primordial power spectrum of curvature fluctuations asmeasured by the Planck collaboration. Our model predicts flux noise with aspectrum given by an $1/f^{2-n_s}$ spectrum, where $n_s=0.96$ is the spectralindex of the near-scale invariant primordial density fluctuations. For thetypical amplitude of this cosmologically generated universal flux noise wetheoretically calculate the average value $\delta \Phi /\Phi_0 =3.41 \cdot10^{-6}$ at 1Hz. These theoretical predictions are in excellent agreement withrecent low-frequency flux noise measurements of various experimental groups.Magnetic flux noise, so far mainly considered as a nuisance for electronicdevices, may thus contain valuable information about fluctuation spectra in thevery early universe.
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