Exciton matter sustained by colossal dispersive interactions due to   enhanced polarizability: Possible clue to ball lightning
  Recently Gilman has pointed out that the material state of a ball lightning is both highly cohesive and flexible. He makes a specific proposal for a cohesive state arising from (colossal) Van-der-Waals attraction between highly polarizable Rydberg atoms produced under a linear lightning. We accept his general suggestions but propose that the colossal Van-der-Waals coupling may also arise from the enhanced polarizability of surrogate molecular clusters, due to the polaron gap narrowing effect. We consider a few illuminating cases and present calculations for the ammonia molecule. Although being unable to identify the exact nature of the surrogate molecules at least for the time-being, we suggest a general scenario of photoexcited vibronic excitons forming a supersaturated surrogate gas phase in which a ball arises as a result of condensation. The orange color of the luminous ball is due to radiative exciton deexcitation and suggests that there may be a unique surrogate material for ball lightning. 
Mladen Georgiev (Institute of Solid State Physics, Bulgarian Academy   of Sciences, Sofia, Bulgaria), Jai Singh (Charles Dar...