So I was trying to demonstrate Snell's law with Hamilton's equations, and when I got the Hamiltonian: $$H = -\sqrt{n^2-p_{1}^2-p_{2}^2}.$$
I had a question about what this Hamiltonian indicates. I mean, we know that, for example, under certain circumstances $H=T+U$, but in this case, what is the physical content of it?
Could someone maybe explain to me what the physical content of this optical Hamiltonian is?
Reference: This is from the book "Lagrangian Optics" by Vasudevan Lakshminarayanan et al., pages 93-95.