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Could dark matter be hiding in plain sight in existing experiments?

Particles called axions could be creating noise in superconducting devices:

Axions were not originally proposed as a solution to the dark matter problem. Instead, they are a possible way to solve a pressing problem in quantum chromodynamics (QCD), the theory of the strong force, which governs quarks and their interactions.

Most interactions in physics work the same if you simultaneously exchange particles with their antimatter counterparts and reverse the direction in which they occur. This is known as CP symmetry (where C stands for charge and P stands for parity). CP symmetry is violated in many interactions involving the weak force, but, experimentally, it appears to be preserved by the strong force. The problem is that QCD appears to break CP symmetry badly, in stark contrast to experimental results.

Physicists have proposed several possible solutions to this problem, extensions to the Standard Model of particles and interactions. The axion is perhaps the simplest of these, as it explains why CP symmetry is mostly upheld in QCD. If this idea is correct, many axions were produced in the moments after the Big Bang, meaning the Universe could be full of them. Thus, if axions exist, they could simultaneously solve the CP and the dark matter problem.

That’s a big if, though it looks as though the experiments to answer this question are pretty easy to conduct.

Posted in SciTech.