2015/02/05 by Jianzhi Han, Han, Jianzhi, Yucai Su +1
Mathematics · #16S50 #17B40 #Commutative Algebra (math.AC) #FOS: Mathematics #Quantum Algebra (math.QA) #math.AC #math.QA #msc:16S50 #msc:17B40
paper · pdf · doi:10.48550/arxiv.1502.01441
arxiv created 2015/02/05 · arxiv updated 2015/02/06
The automorphism groups \rm Aut An and \rm Aut Wn of the polynomial algebra An=C[x1,x2,⋯, xn] and the rank n Witt algebra Wn=\rm Der An are studied in this paper. It is well-known that \rm Aut An for n≥3 and \rm Aut Wn for n≥2 are open. In the present paper, by characterizing the semigroup \rm End Wn∖\0\ of nonzero endomorphisms of Wn via the semigroup of the so-called Jacobi tuples, we establish an isomorphism between \rm Aut An and \rm Aut Wn for any positive integer n. In particular, this enables us to work out the automorphism group \rm Aut W2 of W2.