English Dictionary

empty set

名詞

(set theory) The unique set that contains no elements, denoted ∅ or {}.

日本語の意味

数学において、要素が一つも存在しない集合（空集合）

During the seminar, she explained how the empty set underlies many proofs in set theory.

セミナーで彼女は、要素を一つも含まない集合（∅）が集合論の多くの証明の基礎になっていることを説明した。

意味（1）

(set theory) The unique set that contains no elements, denoted ∅ or {}.

Start with the empty set. We define it as “the set of all objects not equal to themselves,” since there are no such objects. All empty sets have the same members—no members at all! Therefore, as sets they're identical, by definition of identity of sets. In other words, there's only one empty set. This unique empty set is our building block. Next comes the set whose only member is—the empty set. This set is not empty.

empty sets （ plural ）