Is there such a thing as muon fusion? The lower mass would greatly increase tunneling probabilities, right?
Yes, Muon catalyzed fusion.
There are some theories that try to explain the Anomalous Heat Effect by some roundabout muon fusion, that muons are created in more abundance than expected.
I like the Muon Fission Fusion theory, just because it uses muons to explain the primary reaction as well as the secondary one.
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