Under a Lorentz transformation, a spinor living in d dimensions transforms as
ψ(x)→ψ′(x′)=e12λμνΣμνψ(x)
up to some numerical factors in the exponential from convention. This is only true if we're dealing with the orthochronous proper Lorentz transforms SO+(1,3), because the projective spinor representations mean we can just deal with the algebra, and the Σμν are representations of so(1,d−1). How does this change when we want to think about P and T? That is, how does one derive the action of elements of O(1,d−1) on spinors?
The only progress I've made towards understanding this is the coordinate-dependent interpretation put forth in standard texts on QFT, where P and T act with some product of gamma matrices. I was looking for a slightly more general definition.
A related question: is the number of of disconnected components of O(1,d−1) the same for even and odd dimension?