The Broken Line/ Dotted Line

A broken 'line' in 3D space, made of black rectangular bricks breaking up the space. Suspended? Lying on the floor? Black, red?
Think of the various graphic ways in which borders, barriers and demarcations are shown on maps and town plans. How can these be brought into the real 3D world? Regular shapes/ irregular borders? Suspended on wires? Lying flat on surfaces? How does it physically break up the space?
Can one violate the boundary? What are the consequences?
Boundaries / demarcations / social divisions / rank / class / caste
Assumptions, prejudices, expectations.

Demarcation is the opposite of a natural segue, e.g. from 'reality' to 'fiction'.