On: Ask HN: How were the super bowl led torches synced...

[mathgeek]

This is what I would assume. They weren't perfectly synced (although very close), so it appeared to be some sort of localized position detection.

[jwatte → mathgeek]

They weren't perfectly synced, so I would assume the field audience just all pressed the "go" button at the same time (indicated by handlers with headsets, presumably)

Much simpler than localization.