“Physical sciences” refer to scientific disciplines that focus on non-living systems. The four main branches are physics, chemistry, astronomy, and Earth sciences. There are subdisciplines that fall under each of those four main branches of the physical sciences, too. Separating out the physical sciences from life sciences only pertains to general differences in their fields of study, in their focus. It is an easy way to categorize and distinguish one major branch of scientific study from another. Across the disciplines, the same physical laws apply, and there is overlap between some physical and life science fields.
Topics studied under the broad umbrella of the non-living, physical sciences include particle physics, quantum mechanics, thermodynamics, inorganic chemistry, cosmology, meteorology, geochemistry, soil chemistry, oceanography, plate tectonics, climatology, paleoclimatology, glaciology, and much more. There is something to interest everyone. Each of these fields can define a career.