This is a submission for the Gemma 4 Challenge: Build with Gemma 4 I Built a Research Synthesis Engine That Reads 15 Papers and Generates Peer-Reviewed Hypotheses — Powered by Gemma 4 Every researcher knows the feeling: you have a stack of papers, a vague sense that something important is hiding between them, and no time to find it. Individual papers answer narrow questions. The breakthroughs live in the gaps between them. I built LitSynth — a local, fully offline research synthesis engine that ingests up to 15 scientific PDFs, reasons across all of them simultaneously, and produces four structured outputs: cross-paper agreements, contradictions with mechanistic explanations, research gap analysis ranked by importance, and novel falsifiable hypotheses — each one put through a multi-round adversarial peer review loop before it reaches you. This only exists because of Gemma 4's 128K context window and thinking mode. RAG pipelines approximate this. Gemma 4 actually does it.…