I've read that the Zeeman effect can cause a single allowed energy level to split into two, one of which is higher in energy by some value \Delta E'. The other level is shifted down by the same amount.
My question is this: if an electron is in the ground state, the lowest orbital, can it shift even lower by \Delta E'?
Is it possible to go below 0 energy and have a negative energy orbital?
I'm not fully or formally educated on quantum systems. Thank you in advance for the help!