Add instructions for arXiv submission to paper template

content/design/d2.md

@@ -57,19 +57,23 @@ Another advantage of Source Serif Pro is that there is a sans-serif font in the
 
 ## Math fonts
 
-LaTeX uses one font for text and other fonts for math. For consistency, the template sticks with Source Serif Pro for roman math. It also uses Source Serif Pro for all the digits in math and basic punctuation (such as `.`, `?`, `%`, `;`, and ``), so very basic mathematical expressions look the same in math and text. For example, the commands `3.5\%` and `$3.5\%$` produce the same results.
+LaTeX uses one font for text and other fonts for math. For consistency, the template sticks with Source Serif Pro for roman math. It also uses Source Serif Pro for all the digits in math and basic punctuation (such as `.`, `?`, `%`, `;`, and `,`), so very basic mathematical expressions look the same in math and text. For example, the commands `3.5\%` and `$3.5\%$` produce the same results.
 
 ### Greek letters
 
 For the Greek letters in math, the template uses the [Euler font](http://luc.devroye.org/fonts-26139.html). These Greek letters look good, have the same thickness and height as the text letters, and are distinctive. For consistency, neither uppercase nor lowercase Greek letters are italicized.
 
 ### Calligraphic letters
 
-The template also uses the [Euler font](http://luc.devroye.org/fonts-26139.html) for calligraphic letters in math. These calligraphic letters fit well with the other fonts and are very readable.
+The template also uses the [Euler font](http://luc.devroye.org/fonts-26139.html) for calligraphic letters in math. These calligraphic letters fit well with the other fonts and are very readable. The calligraphic letters are produced with the `\mathcal` command.
 
 ### Blackboard-bold letters
 
-The template uses the [Fourier font](https://milde.users.sourceforge.net/LUCR/Math/mathpackages/fourier-symbols.pdf) as blackboard-bold font. It is cleaner than the default blackboard bold font as it does not have serif. And it is slightly thicker than the default font so it matches well with Source Serif Pro and Euler letters.
+The template uses the [Fourier font](https://milde.users.sourceforge.net/LUCR/Math/mathpackages/fourier-symbols.pdf) as blackboard-bold font. It is cleaner than the default blackboard-bold font as it does not have serif. And it is slightly thicker than the default font so it matches well with Source Serif Pro and Euler letters. The blackboard-bold letters are produced with the `\mathbb` command. 
+
+### Bold characters
+
+In the template, it is possible to bold any mathematical character (except blackboard-bold letters). This can be done using the `\bm` command in math. 
 
 ### Mathematical symbols
 
@@ -113,7 +117,7 @@ An URL for the paper can be placed at the bottom of the title page by adding the
 
 ## Headings
 
-The template's headings follow [Butterick's advice](https://practicaltypography.com/headings.html). Section headings are a bit larger than the text (12pt) and bold. Section headings are also centered to clearly separate sections. Subsection headings are bold. And paragraph headings are in italic, so they are noticeable but not too prominent.
+The template's headings follow [Butterick's advice](https://practicaltypography.com/headings.html). Section headings are a bit larger than the text (12pt) and bold. Section headings are also centered to clearly separate sections. Subsection headings are bold. And paragraph headings are in italic, so they are noticeable but not too prominent. These headings are produced with the usual commands: `\section`, `\subsection`, and `\paragraph`.
 
 The template does not tailor formatting for subsubsections and smaller headings. Such small headings are a sign that the paper's organization is too messy, and should be avoided.
 
@@ -123,6 +127,17 @@ The template does not tailor formatting for subsubsections and smaller headings.
 
 As is standard, the text of theorems is in italic—providing subtle emphasis. The theorem label is in small caps—again providing subtle emphasis. For consistency, propositions, lemmas, assumptions, definitions, and so on, are formatted just like theorems. 
 
+The template comes with the following predefined items:
+
++ Theorems: `\begin{theorem} ... \end{theorem}`
++ Propositions: `\begin{proposition} ... \end{proposition}`
++ Lemmas: `\begin{lemma} ... \end{lemma}`
++ Corollaries: `\begin{corollary} ... \end{corollary}`
++ Definitions: `\begin{definition} ... \end{definition}`
++ Assumptions: `\begin{assumption} ... \end{assumption}`
++ Remarks: `\begin{remark} ... \end{remark}`
+
+
 ---
 
 ## Figures
@@ -131,7 +146,7 @@ A figure should be placed at the top of the page where it is first mentioned—n
 
 The figure environment is set up so it is easy to reference a figure (figure 1) or directly a panel in a figure (figure 1A). 
 
-With the command `\note{Text}`, it is easy to enter a note below the figure caption with details about the figure and sources. The note's font size  is 9pt, just like footnotes.
+With the command `\note{Text}`, it is easy to enter a note below the figure caption with details about the figure and sources. The note's font size is 9pt, just like footnotes.
 
 The code for a basic figure with one panel is the following:
 
@@ -159,9 +174,9 @@ Finally, the code for a figure with six panels is the following:
 ```LaTeX
 \begin{figure}[p]
 \subcaptionbox{Panel caption\label{1}}{\includegraphics[scale=0.2]{1.pdf}}\hfill
-\subcaptionbox{Panel caption\label{2}}{\includegraphics[scale=0.2]{2.pdf}}\fspace
+\subcaptionbox{Panel caption\label{2}}{\includegraphics[scale=0.2]{2.pdf}}\\
 \subcaptionbox{Panel caption\label{3}}{\includegraphics[scale=0.2]{3.pdf}}\hfill
-\subcaptionbox{Panel caption\label{4}}{\includegraphics[scale=0.2]{4.pdf}}\fspace
+\subcaptionbox{Panel caption\label{4}}{\includegraphics[scale=0.2]{4.pdf}}\\
 \subcaptionbox{Panel caption\label{5}}{\includegraphics[scale=0.2]{5.pdf}}\hfill
 \subcaptionbox{Panel caption\label{6}}{\includegraphics[scale=0.2]{6.pdf}}
 \caption{Figure caption}
@@ -254,7 +269,7 @@ The template makes it easy to add an appendix at the end of the paper. The appen
 
 All the appendix sections are clearly marked `Appendix` and are numbered as Appendix A, Appendix B, Appendix C, and so on. The appendix subsections are also numbered (for instance, A.1, A.2, B.1, B.2) so they can be referred to. 
 
-All labels in the appendix start with an `A`, so it is clear that they point to some material in the appendix: for instance, corollary A1, figure A2, table A3, or equation (A10). All counters are reset at the beginning of the appendix  (tables, figures, equations, and theorems) so all the labels start at A1, A2, and so on.
+All labels in the appendix start with an `A`, so it is clear that they point to some material in the appendix: for instance, corollary A1, figure A2, table A3, or equation (A10). All counters are reset at the beginning of the appendix (tables, figures, equations, and theorems) so all the labels start at A1, A2, and so on.
 
 ---
 
@@ -264,6 +279,19 @@ Once a research paper gets published, the appendix must often be transformed int
 
 + The abstract is replaced by a table of contents.
 + All the labels from the main text (equation numbers, figure and table numbers, theorem numbers, section numbers) continue to be usable in the online appendix. So the cross-references from main text to appendix are not broken even though the appendix is now in a separate file. [This requires the following](https://www.ctan.org/pkg/xr):
+
     + `appendix.tex` is in the same folder as `paper.tex`.
     + `paper.tex` is compiled first.
-    + The auxiliary file `paper.aux` is available when `appendix.tex` is compiled.
+    + The auxiliary file `paper.aux` is available when `appendix.tex` is compiled.
+
+---
+
+## Submission to arXiv
+
+The template is perfectly compatible with [arXiv](https://arxiv.org/). In particular, the template works without problems under the TeXLive 2023 distribution, which is the LaTeX distribution [currently used by arXiv](https://info.arxiv.org/help/faq/texlive.html).
+
+A paper based on the template can be submitted to arXiv in just three steps once it has been compiled with pdfTeX:
+
+1. Adjust the preamble of the source file `paper.tex`: on line 3, replace `\bibliographystyle{bibliography}` by `\pdfoutput=1`. The `\bibliographystyle{bibliography}` command is not needed because arXiv produces the bibliography directly from the `paper.bbl` file. The `\pdfoutput=1` is required because the paper [is compiled with pdfTeX](https://info.arxiv.org/help/submit_tex.html#pdflatex).
+2. Collect the required files into a folder. There should be four files: the source file `paper.tex`, the bibliography file `paper.bbl`, the style file `paper.sty`, and the figure file `figures.pdf`. 
+3. Zip the folder and upload the zipped file to arXiv.