Can I get into PhD in Physics with a high GRE score and an unrelated masters degree? I recently completed my MBA and have worked in the IT field for the last 7 years. I have an undergraduate degree in mathematics, and have completed 3 physics graduate courses (mechanics, E&amp;M, QM) as an open university student. Is it realistic for me to self study for the physics GRE, get a great score, and then have a chance to be admitted to a physics PhD program?

The physics graduate courses I took were from a master’s school, but I had to pay for these out of my pocket. I though about continuing in that masters program but it is just too expensive given my situation (I have a family and a mortgage).

I want to know if I have a shot at a PhD program without going for the masters and only with a great physics GRE score and a mathematics undergraduate degree.
Typically the only reason that PhD granting institutions in the US give out a master's degree en route to the doctorate is the existence of capitation money in some states that reward them for each advanced degree they grant. You don't need a master's degree. I never got one, and I could have for $50 and two weeks spent converting a couple of journal articles to thesis format. Nobody worth talking to expects you to have an MS when you apply.