Protons have mass and as a result of einstein's field equation dictate that the spacetime is no longer flat. But yet I find in most Quantum Field Theory books the Minkowski flat spacetime metric is used.
Doesn't this imply that the space is flat even with the proton being present ? Or are we making an approximation ? But if it's an approximation, looking at success of QFT it looks like that's a really good approximation to make.
I am unable to picture an electron in spacetime without it bending it. How does one think about this ?
