The Stacks project

Fix typo in formal-defos

Thanks to Xiaowen Hu
http://stacks.math.columbia.edu/tag/06IU#comment-2639

LaTeX

Introduced a macro

\def\Ker{\text{Ker}}

and replace all occurrences of \text{Ker} with \Ker

Whitespace changes

LaTeX: get rid of useless brackets

Versal formal objects

	Now we've got uniqueness of versal formal object (correct
	statement in the correct generality). This introduces a
	different notion of minimality from before -- one which doesn't
	look at what happens on tangent spaces. The result later is then
	going to be that minimality can be read off from what happens on
	tangent spaces, provided we have (S2).

And now we're stuck!

	Our change in part 2 of (S2) was too radical. We changed both
	the assumption and the conclusion and we should have only
	changed to assumption... because currently (S2) is different
	from the original version even in the case of a predeformation
	category, contrary to what we said in commit
	7ab110e3348cb10d7368abe7d79229c34d13c3bf.

	Thus we will back up, change (S2) once more, and review all the
	lemmas involving (S2) to make sure they are still OK.

Cofibered in groupoids

	Formal section with only category theory.

The category C_\Lambda

	This turned out to be quite a bit more interesting than I had
	at first imagined. Can you do this without appealing to the
	naive cotangent complex? I am sure you can, but how much longer
	would it be...? Patches welcome.

Tags: Added new tags

	Due to the new material in the chapter on deformation theory.

New chapter on formal deformation theory

	Written by Alex Perry.