Collections

Selected problems that share a subject or a research tradition. Each leads to its own overview and sources.

Millennium Prize Problems

Five open problems from Clay’s famous prize program, linking mathematics with computation and mathematical physics.

5 problems

The observed universe

Unseen matter, cosmic expansion, energetic particles, and brief radio flashes.

40 problems

Origins and complexity

From the first living systems to complex cells and multicellular organisms, explore several transitions in life’s history.

10 problems

Consciousness and sleep

Experience, dreams, and the roles of sleep: connected subjects with distinct questions and evidence.

4 problems

Primes and integers

Patterns in prime numbers, and equations whose solutions must be whole numbers.

14 problems

Quantum foundations

Measurement, gravity, and black holes challenge our account of quantum physics.

10 problems

Learning and intelligence

Human cognition and machine learning face different questions about learning, generalization, and goals.

32 problems

Genes and development

How do genomes and regulatory systems shape traits, reliable development, and repair?

32 problems

Energy and materials

Generating, storing, and converting energy demands both physical understanding and workable devices.

33 problems

Inside cells

Molecular traffic, cell machinery, patterned shells and signals between cells.

14 problems

Water and waste

Harvesting freshwater, preserving salt barriers, destroying persistent chemicals, and sorting layered plastics.

4 problems

Algebras and modules

Representations, extensions and resolutions that reveal algebraic structure.

4 problems

Dynamics

Repeated maps, billiard trajectories and periodic motion.

5 problems

Algebraic geometry

Polynomial equations define spaces whose shapes, singularities and algebraic cycles pose different open problems.

8 problems

Electronics and photonics

Lasers, clocks, analog circuits and devices for moving quantum information through optical networks.

7 problems

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