What do you mean by "the cause of entropy" ? I would guess that you are talking about a cause of the 2nd law of thermodynamics, which states that the entropy in an isolated system never decreases.Are changes in the frequencies of vibrating strings the cause of entropy?
I personally thinkg the whole notion of information and entropy is really more complicated than what most basic treatments admit.When is informational entropy equal to thermodynamic entropy? What dimensions does information have?
Yes there are a few different issues I see here. First is that some entropies like Gibbs, is constructed from a probability space. Boltzmanns, are constructed instead from a combinatorial approach if microstates. It effectively constructs a kind of discrete probability space.Well, thermodynamic entropy is equivalent to Shannon entropy, when you set k to 1.
Then heat has the same units as information, then heat = information in (0,1) basis.