Ars Technica: A potential hangup for quantum computing: Cosmic rays.
[1]https://arstechnica.com/science/2021/12/cosmic-rays-can-swamp-error-correctio
n-on-quantum-processors/

Jim Bell's comment:

"Shades of alpha-particle-induced soft-errors!!!"

Partial Quote from article:

"Recently, when researchers were [2]testing error correction on Google's quantum
 processor, they noted an odd phenomenon where the whole error-correction scheme
 would sporadically fail badly. They chalked this up to background radiation, a
combination of cosmic rays and the occasional decay of a naturally occurring rad
ioactive isotope."
"It seemed like a bit of an amusing aside at the time—Google having accidentally
 paid for an extremely expensive cosmic ray detector. But the people behind the
processor took the problem very seriously and are back with a new paper that det
ails exactly how the radiation affects the qubits. And they conclude that the pr
oblems caused by cosmic rays happen often enough to keep error-corrected quantum
 computations from working unless we figure out a way to limit the rays' impact.
"

It’s a shame about the rays

"Cosmic rays and radioactivity cause problems for classical computing hardware a
s well. That's because classical computers rely on moving and storing charges, a
nd cosmic rays can induce charges when they impact a material. Qubits, by contra
st, store information in the form of the quantum state of an object—in the case
of Google's processor, a loop of superconducting wire linked to a resonator. Cos
mic rays affect these, too, but the mechanism is completely different."

   (End of partial quote)

   My proposed solution?   Maybe have a portion of the quantum circuitry
   doing 'dummy calculations', whose expected output is known.  If an
   error in those calculations occurs, that will likely indicate a failure
   in the relevant calculstions.

References

   1. https://arstechnica.com/science/2021/12/cosmic-rays-can-swamp-error-correction-on-quantum-processors/
   2. https://arstechnica.com/science/2021/07/google-tries-out-error-correction-on-its-quantum-processor/