Let R and A be commutative rings with identity, and m and n be integers ≥3. Consider when and how an isomorphism E_m(R)E_n(A) can be lifted to an isomorphism between the corresponding Steinberg groups. It was proved ...Let R and A be commutative rings with identity, and m and n be integers ≥3. Consider when and how an isomorphism E_m(R)E_n(A) can be lifted to an isomorphism between the corresponding Steinberg groups. It was proved that, if E_m(R) is isomorphic to E_n(A) then m=n (cf. Ref. [1]). When n≥4, every isomorphism E_n(R)E_n(A) is of the standard type, and it can be naturally and uniquely lifted to an isomorphism from St_n(R) to St_n(A) (cf. Refs. [1] and [2]). However, the case n=3 is different from that n≥4,展开更多
Sharpe once gave a beautiful 4-term decomposition LPLU for infinite Steinberg group; recently Li Fu-an has given a sufficient and necessary condition for 4-term decomposition LWLU of finite Steinberg group over commut...Sharpe once gave a beautiful 4-term decomposition LPLU for infinite Steinberg group; recently Li Fu-an has given a sufficient and necessary condition for 4-term decomposition LWLU of finite Steinberg group over commutative rings. The present note extends the result of [2] to non-commutative rings and studies the decomposition of a finite Steinberg group over local rings.展开更多
This paper deals with a reducible sl(2,C)action on the formal power series ring.The purpose of this paper is to confirm a special case of the Yau conjecture:Suppose that sl(2,C)acts on the formal power series ring via...This paper deals with a reducible sl(2,C)action on the formal power series ring.The purpose of this paper is to confirm a special case of the Yau conjecture:Suppose that sl(2,C)acts on the formal power series ring via(1.1).Then I(f)=(li 1 )⊕(il2 )⊕···⊕(lis)modulo some one dimensional sl(2,C)representations where(i)is an irreducible sl(2,C)representation of i dimension and{li1 ,li2 ,...,lis }{ll1,ll2,...,lr}.Unlike classical invariant theory which deals only with irreducible action and 1-dimensional representations,we treat the reducible action and higher dimensional representations successively.展开更多
基金Project supported by the National Natural Science Foundation of China
文摘Let R and A be commutative rings with identity, and m and n be integers ≥3. Consider when and how an isomorphism E_m(R)E_n(A) can be lifted to an isomorphism between the corresponding Steinberg groups. It was proved that, if E_m(R) is isomorphic to E_n(A) then m=n (cf. Ref. [1]). When n≥4, every isomorphism E_n(R)E_n(A) is of the standard type, and it can be naturally and uniquely lifted to an isomorphism from St_n(R) to St_n(A) (cf. Refs. [1] and [2]). However, the case n=3 is different from that n≥4,
文摘Sharpe once gave a beautiful 4-term decomposition LPLU for infinite Steinberg group; recently Li Fu-an has given a sufficient and necessary condition for 4-term decomposition LWLU of finite Steinberg group over commutative rings. The present note extends the result of [2] to non-commutative rings and studies the decomposition of a finite Steinberg group over local rings.
基金supported by National Natural Science Foundation of China(Grant No.10731030) and PSSCS of Shanghai
文摘This paper deals with a reducible sl(2,C)action on the formal power series ring.The purpose of this paper is to confirm a special case of the Yau conjecture:Suppose that sl(2,C)acts on the formal power series ring via(1.1).Then I(f)=(li 1 )⊕(il2 )⊕···⊕(lis)modulo some one dimensional sl(2,C)representations where(i)is an irreducible sl(2,C)representation of i dimension and{li1 ,li2 ,...,lis }{ll1,ll2,...,lr}.Unlike classical invariant theory which deals only with irreducible action and 1-dimensional representations,we treat the reducible action and higher dimensional representations successively.
