Apparently, the center of the world is not the right question.
Cati pointed me to a text [in French] where the author addresses the question of the center of the world and its treatment by Guy Debord.
He opposes the vision of Georges Bataille who argues that thinking the center of the world as a unique element goes against the immensity that he imagines and that is open: "the world looks like [...] what happens from one to the other, when we're laughing, when we're loving". When there is freedom of communication, as such the center should not be thought: "where there is a center (and a periphery), the center should be fought".
This last sentence reflects very much on the idea of majority/minorities. Peripheries hold most often the energy to invent and create, to be open and receptive... until they become centers, exclusive and selective?