I like the "hallucination" theory (called "Transcranial magnetic stimulation" in wiki article):<p>>Magnetically Induced Hallucinations Explain Ball Lightning, Say Physicists<p>>Powerful magnetic fields can induce hallucinations in the lab, so why not in the real world, too?<p><a href="https://www.technologyreview.com/2010/05/11/203417/magnetically-induced-hallucinations-explain-ball-lightning-say-physicists/" rel="nofollow">https://www.technologyreview.com/2010/05/11/203417/magnetica...</a><p>(2010)