From the poem "Geometry"

I prove a theorem and the house expands:
the windows jerk free to hover near the ceiling,
the ceiling floats away with a sigh.

This is excerpt is found in my Fundamental Ideas of Real Analysis textbook. It is from the poem "Geometry" by Rita Dove. I still have no idea what it means.

Here is the full poem

I prove a theorem and the house expands:
the windows jerk free to hover near the ceiling,
the ceiling floats away with a sigh. 

As the walls clear themselves of everything
but transparency, the scent of carnations
leaves with them. I am out in the open. 

And above the windows have hinged into butterflies,
sunlight glinting where they've intersected.
They are going to some point true and unproven.