?? substitution as application of universal property of free on one (object ...) generator ... ?? green substitution as application of universal property of free on one (?? q-braided object ??? .... ??? .....) generator .... ????? ..... ????? .....

?? getting feeling here of .... ??? hard to believe _really_ universal here .... ???? .... ?? need to check ... ???? ...

?? prasad ... ?? subring as contravariant algebraic analog of quotient space ... kaleidoscope-invariant polynomials ..... ??? ... various conceptual roles thereof ????? ...... ???? (?? somewhat ???) canonical free generating set here ?? ... ??? hazy memories .... ?? "casimir ..." ???? .... ????? ......

?? characteristic and normal subgroups of absolute galois groups ??? .... ???? ..... ?? hmm, some silly duality flipping here ... forgetting basic contravariance of galois correspondence for a bit .... ???? .....

?? rep of gl(n,k1) over k2 ... ??? "field-jumping functor" .... ???? .... ??case where ... ?? some part of representation theory is somewhat k1-independent ... ??? .... ?? overlap with case of "tautological rep" ??? ... ???? ... ???? .....