  If K is a number field, arithmetic duality theorems for tori and complexes of
tori over K are crucial to understand local-global principles for linear
algebraic groups over K. When K is a global field of positive characteristic,
we prove similar arithmetic duality theorems, including a Poitou-Tate exact
sequence for Galois hypercohomology of complexes of tori. One of the main
ingredients is Artin-Mazur-Milne duality theorem for fppf cohomology of finite
flat commutative group schemes.
