Lists of problems

The following articles contain lists of notable problems. This includes unsolved problems, which may refer to several notable conjectures or open problems in various academic fields:

Natural sciences and medicine

• List of unsolved problems in astronomy
• List of unsolved problems in biology
• List of unsolved problems in chemistry
• List of unsolved problems in geoscience
• List of unsolved problems in medicine
• List of unsolved problems in neuroscience
• List of unsolved problems in physics

Mathematics

• List of unsolved problems in mathematics
• List of undecidable problems
• List of NP-complete problems
• List of PSPACE-complete problems
• List of problems in loop theory and quasigroup theory

Social sciences, statistics, and information sciences

• List of unsolved problems in economics
• List of unsolved problems in fair division
• List of unsolved problems in statistics
• List of unsolved problems in computer science
• List of unsolved problems in information theory

Other

• List of philosophical problems
• List of unsolved deaths

See also

• Cold case
• List of ciphertexts
• List of hypothetical technologies
• List of paradoxes
• Unknowability