Infinity symbol Infinity symbol The infinity symbol (sometimes called the lemniscate) is a mathematical symbol representing the concept of infinity. The shape of a sideways figure eight has a long pedigree; for instance, it appears in the cross of Saint Boniface, wrapped around the bars of a Latin cross. However, John Wallis is credited with introducing the infinity symbol with its mathematical meaning in 1655, in his "De sectionibus conicis". Wallis did not explain his choice of this symbol, but it has been conjectured to be a variant form of a Roman numeral for 1,000 (originally CIƆ, also CƆ), which was sometimes
Vanish at infinity the same good property. Vanish at infinity In mathematics, a function on a normed vector space is said to vanish at infinity if For example, the function defined on the real line vanishes at infinity. More generally, a function formula_4 on a locally compact space (which may not have a norm) vanishes at infinity if, given any positive number formula_5, there is a compact subset formula_6 such that whenever the point formula_8 lies outside of formula_6. In other words, for each positive number formula_5 the set formula_11 is compact. For a given locally compact space formula_12, the set of such