📊 Daily pulse · Wed, 24 Jun 2026

Preprint Archives & Aggregators · Pulse

Preprint archives and open-access aggregators have emerged as a structural pillar of modern academic publishing, distributing pre-peer-review or peer-review-bypassing manuscripts globally without paywalls. The dominant infrastructure: arXiv (founded 1991 by Paul Ginsparg, hosted at Cornell University, the original physics-then-CS-then-math-then-quantitative-biology preprint server, with 2.5+ million archived preprints and 200,000+ new submissions annually); bioRxiv (founded 2013 by Cold Spring Harbor Laboratory, the biology preprint server, with 200,000+ archived); medRxiv (founded 2019 jointly by BMJ + Cold Spring Harbor Laboratory + Yale, the medical-research preprint server that became substantially more visible during COVID-19); ChemRxiv (founded 2017 jointly by ACS, RSC, GDCh, CCS, the chemistry preprint server); SSRN — Social Science Research Network (founded 1994, the social-sciences-and-humanities preprint server, acquired by Elsevier 2016); RePEc — Research Papers in Economics (founded 1997, the economics-specific preprint and working-paper aggregator with 4 million+ records); PsyArXiv (the psychology preprint server founded 2016 under Center for Open Science); EarthArXiv (Earth-and-environmental sciences); EngrXiv (engineering); SocArXiv (sociology); LawArXiv (legal scholarship); the broader "rxiv" family across sub-disciplines.\n\nThe complementary open-access aggregators provide unified discovery infrastructure: DOAJ (Directory of Open Access Journals — covers 20,000+ peer-reviewed open-access journals globally), CORE (the largest open-access research aggregator with 280+ million open-access articles), Semantic Scholar (the AI-powered academic-search engine from Allen Institute for AI, covering 200+ million papers with substantial post-2020 LLM-and-AI-enhanced search and Q&A capabilities), Google Scholar (the dominant academic-search index, while not strictly open-access also surfaces preprints and free-PDF copies of paywalled work), OpenAlex (the open scholarly-metadata aggregator from OurResearch, the post-2022 successor to Microsoft Academic Graph), Unpaywall (the browser extension and API that surfaces free-to-read versions of paywalled papers).\n\nIndia's preprint-and-open-access infrastructure includes the Open Access India advocacy network, the substantial Indian-research output uploaded to arXiv-and-bioRxiv-and-medRxiv (Indian researchers contribute substantial preprint-volume across mathematics, computer science, biology, medicine), the Shodhganga thesis-and-dissertation repository at INFLIBNET (covering 600,000+ Indian PhD theses), Shodhgangotri synopsis-repository, the National Digital Library of India (NDLI launched 2014 by IIT Kharagpur on behalf of MHRD), the substantial open-access-publishing initiatives through CSIR, ICAR, and the broader Indian research-council network. The post-2014 Open Access Policy of the Indian government mandates open-access deposit of publicly-funded research output. The post-2024 emergence of Indian-origin AI-powered research-discovery tools and the substantial Indian-research-AI infrastructure provides additional discovery pathways.\n\nFor a globally-mobile researcher, the preprint-and-open-access infrastructure provides effectively-universal cross-border-access. The post-2020 substantially-accelerated open-access publishing and Plan S compliance has reduced access-friction substantially though substantial paywalled-publication remains. The AI-and-LLM-powered research-search tools (Semantic Scholar with its post-2022 LLM integration, Elicit, Consensus, Scite, the broader AI-research-search ecosystem that has emerged through 2022-2024) have substantially reshaped how researchers discover and synthesise literature.\n\nCross-references: preprint archives intersect with all journal-roots and paper-roots, plus journal-root-cs (where arXiv-first culture is strongest), journal-root-physics (the original arXiv discipline), academy-natural-sciences, the broader research-and-discovery ecosystem.