Maslov Index and a Central Extension of the Symplectic Group
نویسنده
چکیده
In this paper we show that over any field K of characteristic different from 2, the Maslov index gives rise to a 2-cocycle on the stable symplectic group with values in the Witt group. We also show that this cocycle admits a natural reduction to I2(K) and that the induced natural homomorphism from K2Sp(K)→ I2(K) is indeed the homomorphism given by the symplectic symbol {x, y} mapping to the Pfister form 〈1, −x〉 ⊗ 〈1, −y〉. Mathematics Subject Classifications (1991): 11E81, 19CXX
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