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What is a good notation for the set'set' (or stack if you insist) of all principal G bundles over all'all' spaces for given G? BG is way over used. How about Bun(G)?
# The set' of all principal G bundles over all' spaces
What is a good notation for the set' (or stack if you insist) of all principal G bundles overall' spaces for given G? BG is way over used. How about Bun(G)?