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Why does collapsing a bubble with a sound wave produce light?

My thoughts on a reddit discussion  https://www.reddit.com/r/AskPhysics/comments/1lwxxc3/comment/n2jx8gp/?utm_source=share&utm_medium=mweb3x&utm_name=mweb3xcss&utm_term=1&utm_content=share_button The collapsing of a bubble with sound wave leads to the emission of light in a phenomenon known as sonoluminescnce.  The bubble collapse is rapid and the gas inside the core doesn't have time to exchange heat with the surroundings as it's compressed rapidly leading to what is known as adiabatic compression.  This compression heats up the gas to very high temp. The exact temperatures are inferred from the spectrum of emission which is thought to be a blackbody. But some sophisticated models have also been developed that put the temp in the range 5000k-20000k some even higher.  There's also debate on whether the bubble emission spectrum is truly a blackbody or is it line emission or bremsstrahlung? Personally I think its a mix of all three. The pressures create...