phase change
phase transition
state change
physical change

I hadn't thought about physical changes being involved, but you're probably right.

It was still hard to get used to the physical changes in her body.

The only physical change should be that she is no longer able to have children.

Under the strong light she could finally see what both of them had meant about physical changes.

Over the years, the magazine has gone through a number of physical changes.

A number of physical changes are common when the patient is near death.

The physical changes were nothing compared to what went on in your mind.

Very few, even those who knew him well, would have noticed his physical changes.

Four decades later, in the 1910s and '20s, the only major physical changes were made to the building.

Even though he's gone through a major physical change, his personality hasn't really changed.