More studies on metamaterials mimicking de Sitter space

We estimate the dominating frequencies contributing to the Casimir energy in a cavity of meta- materials mimicking de Sitter space, by solving the eigenvalue problem of Maxwell equations. It turns out the dominating frequencies are the inverse of the size of the cavity, and the degeneracy of these frequencies also explains our previous result on the unusually large Casimir energy. Our result suggests that carrying out the experiment in laboratory is possible theoretically.