Undecidable (original) (raw)

TOPICS

Algebra Applied Mathematics Calculus and Analysis Discrete Mathematics Foundations of Mathematics Geometry History and Terminology Number Theory Probability and Statistics Recreational Mathematics Topology

Alphabetical Index New in MathWorld

• Foundations of Mathematics
• Logic
• Decidability

Not decidable as a result of being neither formally provable nor unprovable.

See also

Gödel's First Incompleteness Theorem, Gödel's Second Incompleteness Theorem, Recursively Undecidable, Rice's Theorem, Richardson's Theorem

Explore with Wolfram|Alpha

More things to try:

• 129th Boolean function of x,y,z
• circle, diameter=10
• grad of a scalar field

Cite this as:

Weisstein, Eric W. "Undecidable." FromMathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/Undecidable.html

Subject classifications

• Foundations of Mathematics
• Logic
• Decidability