Mathematics
The enduring conjectures
Explore the great conjectures and open problems that have shaped mathematics. Some have resisted generations of effort; others mark the newest frontiers of research.
As long as a branch of science offers an abundance of problems, so long is it alive; a lack of problems foreshadows extinction or the cessation of independent development.
Start with the icons
The iconic 13
The questions that define modern mathematics — most have stood for a century or more.
Riemann Hypothesis
Number theory · 1859Birch–Swinnerton-Dyer Conjecture
Number theory · 1965Strong Goldbach Conjecture
Number theory · 1742Twin Prime Conjecture
Number theory · 1849Collatz Conjecture
Number theory · c. 1937Hilbert's Twelfth Problem
Number theory · 1900Hodge Conjecture
Algebraic geometry · 1950Smooth four-dimensional Poincaré conjecture
Geometry and topology · c. 1960Three-dimensional Navier–Stokes existence and smoothness
Partial differential equations · 1934Weak cosmic censorship (future-null-infinity form)
Partial differential equations · 1969Uniform finiteness in Hilbert's sixteenth problem
Dynamical systems · 1900versus
Theoretical computer science · 1971Yang–Mills existence and mass gap
Mathematical physics · 2000Choose your depth
Browse by prominence
Every record carries one of three prominence tiers, so you can start famous and go deep.
Iconic13 problems
The most famous open questions in mathematics — the problems whole subjects are organized around.
LandmarkLandmark137 problems
Field-shaping problems that every specialist knows, many with decades of partial progress.
MajorMajor156 problems
Substantial open questions under active pursuit inside their own research communities.
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Browse by field
Each problem has one primary home; cross-field links are preserved on its page.
- Geometry and topology67
- Number theory60
- Analysis and functional analysis58
- Algebra and representation theory57
- Combinatorics50
- Theoretical computer science43
- Algebraic geometry37
- Graph theory36
- Mathematical physics31
- Discrete geometry30
- Dynamical systems25
- Logic and foundations23
- Probability theory21
- Partial differential equations20
- Operations research15
- Information theory11
- Mathematical optimization10
- Game theory and mathematical economics6
- Numerical analysis2
- Statistics2
- Control theory1