Is it a Problem that Physics is Mathematical?

In her paper 'Does the Mathematical Nature of Physics Undermine Physicalism?' Susan Schneider draws attention to a much neglected challenge to physicalism, arising from its mathematical vocabulary. Whilst I agree with Schneider that the mathematical nature of physics is a concern for the physicalist, I disagree with her concerning the essence of the problem. I argue on the basis of Newman's problem that a purely mathematical description cannot entirely characterize concrete reality. The physicalist can avoid Newman's problem by emphasizing the causal or nomic elements of physics, which ensure that it is not purely mathematical. However, physicalism on such a construal is a form of causal structuralism, which I argue involves either a vicious regress or a vicious circularity.