What should be the ideal number of authors in a paper? Of course there's no simple answer to this question and it it depends on many questions, like the field of the publication.
But here is my rule of thumb: The list of authors should not be longer than the abstract.
But here is my rule of thumb: The list of authors should not be longer than the abstract.
Clearly, some guys go way beyond this limit. Take a look at this paper, with 2,991 authors! (I saw this in Leo Monasterio's book Survival Guide to University Life).
Judging by the abstract, I can't understand a bit, except that it is has something to do with the Large Hadron Collider (LHC), and that's enough to earn my respect.