Let k be a p-adic field and K a function field of a curve over k. It was proved in ([PS3]) that if p not equal 2, then the u-invariant of K is 8. Let l be a prime number not equal to p. Suppose that K contains a primitive l(th) root of unity. It was also proved that every element in H-3(K,Z/lZ) is a symbol ([PS3]) and that every element in H-2(K,Z/lZ) is a sum of two symbols ([Su]). In this article we discuss these results and explain how the Galois cohomology methods used in the proof lead to consequences beyond the u-invariant computation.
机构:
Kyushu Univ, Grad Sch Math, Nishi Ku, Fukuoka 8190395, Japan
Kyushu Univ, Grad Sch Math, Nishi Ku, Fukuoka 8190395, Japan
Univ Philippines, Inst Math, Quezon City 1101, PhilippinesKyushu Univ, Grad Sch Math, Nishi Ku, Fukuoka 8190395, Japan