The Stacks project

Try to use L/K notation for field extensions

We could also try to consistenly use "field extension" and not just
"extension" and consistently use "ring extension", etc.

Update proof Hilbert Nullstellensatz

Thanks to yogesh
https://stacks.math.columbia.edu/tag/00FV#comment-5862

Be more careful about Jacobson radical

Thanks to Brian Conrad
https://stacks.math.columbia.edu/tag/0AMD#comment-3650
https://stacks.math.columbia.edu/tag/0CT7#comment-3651
https://stacks.math.columbia.edu/tag/0BC6#comment-3652
https://stacks.math.columbia.edu/tag/0D48#comment-3653

Use the chapter on fields more

Cosmetic change

	Given a named theorem, such as Chevalley's theorem, we now code
	this as

	\begin{theorem}[Chevalley's theorem]
	\label{theorem-chevalley}

	and not as

	\begin{theorem}
	\label{theorem-chevalley}
	(Chevalley's Theorem.)

Normalize use of item labels

	Also check for this in parse.py

LaTeX: \Spec

	Introduced the macro

	\def\Spec{\mathop{\rm Spec}}

	and changed all the occurences of \text{Spec} into \Spec.

Started tags infrastructure

	new file:   scripts/add_tags.py
	modified:   scripts/functions.py
	new file:   tags/initial_tags
	new file:   tags/tags

More neurotic changes

Clean up labels and references
Add more stringent reference checking to parse.py

	modified:   algebra.tex
	modified:   algebraic.tex
	modified:   categories.tex
	modified:   constructions.tex
	modified:   desirables.tex
	modified:   flat.tex
	modified:   fpqc-descent.tex
	modified:   morphisms.tex
	modified:   schemes.tex
	modified:   scripts/functions.py
	modified:   scripts/make_index.py
	modified:   scripts/parse.py
	modified:   sets.tex
	modified:   sheaves.tex
	modified:   simplicial.tex
	modified:   sites.tex
	modified:   stacks.tex
	modified:   topology.tex

Images for finite type maps of Noetherian Jacobson rings explained

	modified:   algebra.tex
	modified:   topology.tex

Moved Noetherian permanence earlier

	modified:   algebra.tex

Small fixes due to previous commit on Hilbert Nullstellensatz

	modified:   algebra.tex

Moved Hilbert Nullstellensatz earlier and expanded it.
Small changes to Jacobson story

	modified:   algebra.tex
	modified:   topology.tex

Fixed proof of the Hilbert Null Stellen Satz

	modified:   algebra.tex

	modified:   algebra.tex

	modified:   algebra.tex

	modified:   algebra.tex
	modified:   topology.tex