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• CommentRowNumber1.
• CommentAuthorUrs
• CommentTimeJan 16th 2018

we didn’t have face

• CommentRowNumber2.
• CommentAuthorTodd_Trimble
• CommentTimeJan 16th 2018

What’s your source for this? Wikipedia seems to disagree that it has to be 2-dimensional.

• CommentRowNumber3.
• CommentAuthorUrs
• CommentTimeJan 16th 2018

Sure. I don’t think we need Wikipedia for that. I added a line.

• CommentRowNumber4.
• CommentAuthorTim_Porter
• CommentTimeJan 16th 2018

I have seen ’facet’ also used and ’face’ might be restricted to when it can be ’face of’ something higher dimensional (usually by 1, not more).

• CommentRowNumber5.
• CommentAuthorUrs
• CommentTimeJan 16th 2018
• (edited Jan 16th 2018)

By the way, while my entry was clearly stubby, it never said that a face has to be 2-dimensional. If we want to have a fight, I’d rather we have it over something substantial. I am announcing these kinds of trivial edits in order to stick to the etiquette of this particular forum, which, in its role as the “talk-pages” of the nLab, is the place to record edits to the $n$Lab, trivial as they may be. I’d hope this goes without saying.

I won’t further touch this entry. All I needed is for a link to “face” in the discussion of loop order of Feynman diagrams to point somewhere. Anyone who feels encyclopedic is invited to work on making this entry the definite source for face-theory on the web.

• CommentRowNumber6.
• CommentAuthorMike Shulman
• CommentTimeJan 16th 2018

it never said that a face has to be 2-dimensional

It did say that a “2-cell” is called a face. I suppose one might find exotic structures in which “2-cells” need not be 2-dimensional, but usually they are.

• CommentRowNumber7.
• CommentAuthorTodd_Trimble
• CommentTimeJan 16th 2018

Urs #5: I think you overreacted. My question was an honest one, and I wasn’t picking a fight.