This is a joint work with Liuzhen. We investigated the oscillation map introduced by Justin Moore and found more combinatorial properties. It turns out that these properties can be used to construct an L group with non-Lindelof square. These can also reduce the dimension of certain spaces. We will construct, for each natural number n, an L space whose n-th power is an L space while n+1-th power is not. At last, we will discuss higher dimensional properties of the oscillation map itself.