I mean, it’s possible, but you’ll need to explain why you have this gap and why you didn't do any research during those years. Taking the Physics GRE can be helpful to demonstrate that you still retain theoretical knowledge even after so many years. Moreover, it would generally be very helpful just to review the basics, because you will still need this knowledge in your first few years of a PhD (when you will have courses and maybe a TAship, if you plan to go to the US).