Geometric measure of entanglement of symmetric d qubits is polynomial time computable
We give a simple formula for finding the spectral norm of d mode symmetric tensor in two variables over the complex or real numbers in terms of the complex or real roots of a corresponding polynomial in one complex variable. This result implies that the geometric measure of entanglement of symmetric d qubits is polynomial time computable. We discuss a generalization to d mode symmetric tensor in more than two variables.