THE RECORD
What changed
Tesla's polyphase patents, Westinghouse's commercialization and Niagara hydroelectric works advanced AC grids.
EVIDENCE
What remains
Patents, machines, transformers and station records document standards competition.
WHY IT MATTERS
Why it matters
It created the spatial structure of modern grids by moving power from source to users.
OPEN QUESTION
Where interpretation begins
Reducing it to Tesla versus Edison hides engineers, companies and safety politics.