Each problem states how progress is verified and what counts as a contribution. Besides the problems curated here, the catalogue includes open conjectures from Formal Conjectures (with Lean statements), optimization constants and the AlphaEvolve problems. Know one that belongs here? Propose a problem.
6 shown
Determine how much of the atmospheric methane increase since 2007 comes from wetlands, fossil sources and agriculture versus a weakening sink, using public observations and reproducible inversions.
Establish whether El Nino-Southern Oscillation events can be predicted skilfully at lead times beyond about a year, with skill demonstrated in fair, reproducible hindcasts.
Determine whether marine ice-sheet and ice-cliff instabilities can drive rapid Antarctic retreat this century, and how much they widen sea-level projections.
Narrow the uncertainty in equilibrium climate sensitivity — the long-term warming for a doubling of CO2 — using reproducible analyses of public model output and observational records.
Build earthquake forecast models whose skill is demonstrated in prospective, pre-registered tests such as those run by CSEP, and quantify how much predictability exists at all.
Why have stock returns historically exceeded safe-asset returns by far more than standard consumption-based models with plausible risk aversion predict? Reproducible calibrations on public data count as B-style evidence.
