A short proof that Diffc(M) is perfect
نویسندگان
چکیده
In this note, we follow the strategy of Haller, Rybicki and Teichmann to give a short, self contained, and elementary proof that Diff0(M) is a perfect group, given a theorem of Herman on diffeomorphisms of the circle.
منابع مشابه
A SHORT PROOF OF A RESULT OF NAGEL
Let $(R,fm)$ be a Gorenstein local ring and$M,N$ be two finitely generated modules over $R$. Nagel proved that if $M$ and $N$ are inthe same even liaison class, thenone has $H^i_{fm}(M)cong H^i_{fm}(N)$ for all $iIn this paper, we provide a short proof to this result.
متن کاملOn $alpha $-semi-Short Modules
We introduce and study the concept of $alpha $-semi short modules.Using this concept we extend some of the basic results of $alpha $-short modules to $alpha $-semi short modules.We observe that if $M$ is an $alpha $-semi short module then the dual perfect dimension of $M$ is $alpha $ or $alpha +1$.%In particular, if a semiprime ring $R$ is $alpha $-semi short as an $R$-module, then its Noetheri...
متن کاملOn the oriented perfect path double cover conjecture
An oriented perfect path double cover (OPPDC) of a graph $G$ is a collection of directed paths in the symmetric orientation $G_s$ of $G$ such that each arc of $G_s$ lies in exactly one of the paths and each vertex of $G$ appears just once as a beginning and just once as an end of a path. Maxov{'a} and Ne{v{s}}et{v{r}}il (Discrete Math. 276 (2004) 287-294) conjectured that ...
متن کاملA short proof that Diff0(M) is perfect
In this note, we follow the strategy of Haller, Rybicki and Teichmann to give a short, self contained, and elementary proof that Diff0(M) is a perfect group, given a theorem of Herman on diffeomorphisms of the circle.
متن کاملA short remark on the result of Jozsef Sandor
It is pointed out that, one of the results in the recently published article, ’On the Iyengar-Madhava Rao-Nanjundiah inequality and it’s hyperbolic version’ [3] by J´ozsef S´andor is logically incorrect and new corrected result with it’s proof is presented.
متن کامل