Theres graded local duality which works just like local duality; however, it requires that A0 is a field. I've had some luck making things work when A_0 is not a field, but then the local duality becomes more derived. Specifically, Matlis duality, which is an exact functor in the graded local case, gets replaced by operatornameRHomA0(−,A0), the derived graded hom over A0 into A0. Then, at least in some cases I've looked at, the local cohomology Rtau satifies the equation
Rtau(M)=operatornameRHomA0(operatornameRHomA(M,A),A0)[d](l)
This should be true when the ring A is 'relatively Gorenstein over A0', which means that operatornameExtiA(A0,A) is non-zero for a single i=d, and operatornameExtdA(A0,A)=A(l).
As for translating this to Serre duality, there should be an exact triangle Rtau(M)toMtoRGamma(M)to relating the local cohomology to the derived global sections.
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