revtex's frontmatter shares its page: three quarters of page one were blank

[tannevaled]

Six papers in the corpus are too long with nothing reported missing. The smallest of them, 2203.15077, told the whole story:

	page 1, ink
gotex	y 70..141 of 660
reference	y 44..603

Three quarters of our first page was blank. The title block landed on it and the page ended.

Why

In revtex's reprint (two-column) mode the frontmatter — title, authors, affiliations, abstract — became a one-column region of its own. Regions are page-aligned, because \onecolumn and \twocolumn both \clearpage, so the body started on page two.

Reduced to ten lines: one column fills the page correctly, two columns never do, and plain article with [twocolumn] is fine — so it is not the general mechanism, it is the revtex path.

The fix, which the code already had a name for

revtex's frontmatter is \twocolumn[...] in all but name: a full-width block across the top of the region's first page, with the body flowing in two columns below it on that page. paginateTwoColList already places exactly that — its own comment calls it "the region's own \twocolumn[span]/frontmatter span". So the frontmatter is handed over as the region's span instead of becoming a region.

	page 1, ink
before	y 70..141
after	y 70..613
reference	y 44..603

A frontmatter taller than the text block has no page to share, and a span is placed whole and cannot be broken, so that case keeps the old behaviour — with its own test.

Measured

157 arXiv papers, against a baseline rebuilt from the current main: Σ|err| 335 → 326 (−9), glyphs +0, no paper losing content. Thirteen papers each lose the wasted page, and six land exactly on their reference — 2203.15077, 2307.10113, 2308.02700, 2310.04950, 2403.04273, 2408.08814.

Sixteen of the 154 papers with a valid reference are revtex, so this is over 10% of the corpus.

Two test helpers were blind

treeText and pageChars walked only the main vertical list, so a span was invisible to them: a revtex title block looked absent when it had merely moved. Both collect the regions' spans now — which is what a figure*/table* band needs too. The rendered output is byte-identical in text: pdftotext gives the same title, authors and abstract before and after.

TestRevtexReprintTwoColumn asserted the old contract ("a one-column frontmatter region precedes a two-column body region") and now asserts the new one.

🤖 Generated with Claude Code