How about a Polymath-like Project for Theoretical Physics?

This is not another suggestion for something like the Polymath Project.

Rather, this is a more modest proposal, modeled around The Stacks Project and The CRing Project. The Stacks Project describes itself as:

an open source textbook and reference work on algebraic stacks and the algebraic geometry needed to define them.

The CRing Project is also an open source textbook (on commutative algebra), although it is perhaps at a slightly more elementary level:

The present project aims, however, at producing a work suitable for a beginning undergraduate with a background in elementary abstract algebra.

Do you guys think it would be a good idea to start something like this? An open-source textbook on, say, General Relativity or Quantum Field Theory? I think it'd be a good idea for a number of reasons:

- While things might seem slow in the beginning, it could eventually become encyclopedic - a standard reference!
- Sections of this textbook may be revised individually and more frequently, so that, as a reference, it won't become obsolete.
- It'll be a good place for an advanced undergraduate/beginning graduate student to start learning a subject.
- It's a free textbook.
- It'll get the users of this website used to sharing ideas, throwing drafts of chapters back and forth with comments and criticism.

If we'd like to have something like the Polymath Project, we need to get used to this way of operating, and I think this would be good practice. That we get a good textbook out of it is only a happy consequence. I know that there are a number of reasons not to do this - it's time-consuming, difficult to coordinate and there are already a large number of really good textbooks out there.

I still think it'd be nice to actually be involved in something like this, so I thought I'd see if there were any takers. So, any thoughts?

**EDIT**

Prof. Shor is right. In light of his comment:

*Are there any areas of physics you'd like to see an open-source textbook on?*

This post has been migrated from (A51.SE)