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• CommentRowNumber1.
• CommentAuthorUrs
• CommentTimeFeb 10th 2014

I have given external tensor product its own entry.

What I would really like to do for the moment is record there sufficient conditions under which the fiber over $X_1 \times X_2$ is generated from external tensor products. I have added two references that discuss this for quasicoherent sheaves, but otherwise there is no discussion yet. Am being interrupted now.

(What I really want eventually is conditions such that $Mod(X_1 \times X_2) \simeq Mod(X_1) \otimes_{Mod(\ast)}Mod(X_2)$)

• CommentRowNumber2.
• CommentAuthorUrs
• CommentTimeJul 15th 2022

added a textbook reference, for completeness:

• CommentRowNumber3.
• CommentAuthorDmitri Pavlov
• CommentTimeJul 15th 2022

Corrected the authors: it’s three authors, not one:

• CommentRowNumber4.
• CommentAuthorUrs
• CommentTimeJul 16th 2022

That’s what I used to think, but when I grabbed the reference yesterday and looked at its publisher page here I saw a cover showing only Greub as author – which made me wonder to myself that maybe only the later volumes are coauthored.

I should have known better of course. And on another page here the publishing house lists three authors but chooses to heavily misspell Greub’s name. (Apparently these pages are all computer-generated with no editor looking over them.)

• CommentRowNumber5.
• CommentAuthorDmitri Pavlov
• CommentTimeJul 16th 2022

(Apparently these pages are all computer-generated with no editor looking over them.)

Yes, these are OCRed scans, so they also misspelled Halperin and the title of the book (“De Rbam”)!

• CommentRowNumber6.
• CommentAuthorUrs
• CommentTimeJul 16th 2022

Yes, clearly they are not re-investing the revenue they make from exploiting academia. The joke is on us.

I had been well aware of the general phenomenon, but that they now auto-generate false covers for their own publications did catch me off-guard.