The way this challenges the viewer to examine their perceptions is marvelous. There is no natural perspective - we could be seeing a floor or a ceiling. What kind of light casts its own shadow? . . and then more light!? Nice work.
I love this very much. It's so well focused: the eye goes right and follows the sharp crack, while the thick black space in the centre goes upper and to the left, dividing the square into two practically symmetric triangles.