This is a textbook on informal homotopy type theory. It is part of the Univalent foundations of mathematics project that took place at the Institute for Advanced Study in 2012/13.
License
This work is licensed under the Creative Commons Attribution-ShareAlike 3.0 Unported License.
Distribution
Compiled and printed versions of the book are available at the homotopy type theory website, and nightly builds are available on the github wiki.
Editing the book
This book is not a community project, but we do welcome our readers to suggest improvements. The best way to propose an edit is to open a pull request with your suggested change. You can also open an issue if you do not have a concrete proposal yet. The issues and the pull requests are dedicated to improvements, questions, and other issues pertaining to the HoTT book itself. General discussions about homotopy type theory and topics related to the wider HoTT community are welcome at the homotopytypetheory google group or at the HoTT zulip. For further directions about editing the book, see the guidelines for contributions
Code of conduct
For many, the HoTT book is their introduction to our subject and our diverse community, including people from any nationality, gender identity, sexual orientation, race, color, ability, and background. In order to ensure for everyone a welcoming and inclusive environment in our discussions, we follow the guidelines of the GitHub code of conduct. You can expect from the authors and any participant that we are kind and respectful in discussions, that we use inclusive language, and that we do our best to understand each other's different perspectives. It might not always be that we accept the change in the way you proposed it, but we always value your input, regardless of your level of experience or status within the community.
Prerequisites and compilation
To compile the book for yourself you need a fairly new version of LaTeX.
Texlive 2012 is confirmed to work. You might need
to install some packages; see main.tex
for packages that are used by the book.
BasicTeX, which is a minimalistic
version of MacTeX, is confirmed to work once the following packages have been
installed: tlmgr
, install
, braket
, comment
, courier
, enumitem
,
helvetic
, mathpazo
, nextpage
, ntheorem
, palatino
, rsfs
, stmaryrd
,
symbol
, titlesec
, wallpaper
, wasy
, wasysym
, xstring
, zapfding
.
You also need the make
utility. The book is a fairly complex piece of LaTeX
code. Also, the file version.tex
is generated on the fly, so you will need the
make
utility with which you can compile the main files, as follows:
make hott-online.pdf
-- the book appropriate for online reading, with colors and green linksmake hott-ebook.pdf
-- the book with small margins, suitable for ebook readersmake hott-ebook-wide.pdf
-- the book with small margins, suitable for ebook readers, wider pagemake hott-ebook-narrow.pdf
-- the book with small margins, suitable for ebook readers, narrower pagemake hott-letter.pdf cover-letter.pdf
-- the book in black & white, letter paper format, for printing at home, as well as a color cover (just two pages)make hott-a4.pdf cover-a4.pdf
-- the book in black & white, A4 paper format, for printing at home, as well as a color cover (just two pages)make hott-arxiv.pdf
-- the version that is uploaded to arXivmake hott-letter-exercises.pdf
-- the book in black & white, letter paper format, but with exercises one-per-pagemake hott-a4-exercises.pdf
-- the book in black & white, A4 paper format, but with exercises one-per-pagemake hott-ustrade.pdf cover-lulu-hardcover.pdf cover-lulu-paperback.pdf
-- the book in US Trade format, without cover, used for the bound copy available at http://lulu.com/make exercise_solutions.pdf
-- (some) solutions to exercisesmake errata.pdf
-- errata for the HoTT Book, first edition
Note: once make
is run so that version.tex
is generated, you need not run make
every time you make
a change to the source file. You can just perform the usual LaTeX cycle from your favorite editor.
make
Compiling without If you do not have make
(for example, because you are on MacOS and you did not
install the XCode command-line utilities), you can still fake it as follows.
Create the file version.tex
and put in it (where "Joe Hacker" should be
replaced with your name):
\newcommand{\OPTversion}{Joe-Hacker-version}
Then use whatever tools you normally do to compile LaTeX. The main LaTeX files are called
hott-XXX.tex
. But you really should have make
, you know.