Room 5 of 11 · Middle floor
The Hinge
“Can a door change what comes next?”
Lamp waiting
▶ Hear the storyteller tell this roomLook
A small door with a brass hinge. The room on each side is arranged differently.
Try
Walk the doll through the door. Watch her card.
Notice
Try the experiment first. Then this will fill in.
What keeps this room working?
Crossing the threshold really changes the arrangement.
What would break this room?
If crossing made no difference and everything looped back as though nothing happened.
Child-sized version
“Some doors really change what comes next.”
Try to break the room
For grown-upsShow me the math
A local map works on one patch. Where two patches meet, there is a rule for translating one map into the other. No single map is required to cover both sides.
- Chart
- A local map that works on one patch.
- Transition function
- How to translate one chart into the next where they overlap.
- Local, not global
- Each side has a true map. Neither map is the map of everything.