Question

Can we find a unified theory of physics?

Answer 1

Einstein intensely searched for, but ultimately failed to find, a unifying theory. (But see:Einstein–Maxwell–Dirac equations.) More than a half a century later, Einstein's dream of discovering a unified theory has become the Holy Grail of modern physics.

Answer 2

In physics, forces can be described by fields that mediate interactions between separate objects. ... Later, Einstein and others attempted to construct a unified field theory in which electromagnetism and gravity would emerge as different aspects of a single fundamental field