[smogcutter]

This is me being dense, but I don't see the connection to parent's question. Is it that the demon uses information (the speed of the particles?) to perform work (decrease entropy)? But also not really, bc that would violate the 2nd law of thermodynamics? I understood parent's question to be what the heck does "information" mean in this context to begin with. My question too, because I'm pretty sure I've got the wrong answer myself.

[Chabs]

Information as actual physical property (as opposed to a human construct) is basically the only way we found to solve Maxwell's demon seemingly reducing entropy.

Specifically, the entropy within the box gets converted into information inside the demon's "head", which eventually gets radiated away as entropy outside the box. This way, the box's entropy falls, but the entropy of universe as a whole is raised (or at least maintained).