not surprisingly, SHA2 for example is something like 7th (if i remember correctly) degree linear system in its core with 2 highly-non-linear (and non-continous,

not surprisingly, SHA2 for example is something like 7th (if i remember correctly) degree linear system in its core with 2 highly-non-linear (and non-continous, bitshift type) components added to 7th and 4th degrees i.e. something like this: X(n+1) = I X(n) + Y(n) where "I" is a shifted diagonal identity matrix and Y(n) is vector with 7th and 4th components being non-zero. As one'd expect and require for a good hash function - such dynamic system is highly chaotic.