set theory

American  

noun

1. the branch of mathematics that deals with relations between sets.

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set theory British  

noun

1. maths the branch of mathematics concerned with the properties and interrelationships of sets

2. logic a theory constructed within first-order logic that yields the mathematical theory of classes, esp one that distinguishes sets from proper classes as a means of avoiding certain paradoxes

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Etymology

Origin of set theory

First recorded in 1940–45

Example Sentences

In order to investigate the cardinality of the real numbers in more detail, you must extend the current set theory to include other basic statements.

From Scientific American

It would be little comfort to Cantor that his work was the foundation of a whole new branch of mathematics: set theory.

From Literature

Causal set theory, another contender for a theory of quantum gravity, posits that space and time are made of more fundamental components as well.

From Scientific American

There are many different ways to construct the disjoint union using the axioms of set theory, which will not produce exactly the same set but will, necessarily, produce isomorphic ones.

From Scientific American

It is thus impossible to solve CH using the usual axioms of set theory.

From Scientific American