almost all papers on arXiv are done in latex, you upload the source and they compile it on their servers. that’s a lot of papers! it’s most of math, CS, and phy

almost all papers on arXiv are done in latex, you upload the source and they compile it on their servers. that’s a lot of papers! it’s most of math, CS, and physics, and some economics. it’s probably true that most papers aren’t written in LaTeX but I’m confident most people writing in LaTeX are writing scientific papers.