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
Hilbert symbol (for "n" prime) used the power residue symbol when "K" has residue characteristic coprime to "n", and was rather complicated when "K" has residue characteristic dividing "n". The Hilbert symbol is (multiplicatively) bilinear: skew symmetric: nondegenerate: It detects norms (hence the name norm residue symbol): It has the "symbol" properties: Hilbert's reciprocity law states that if "a" and "b" are in an algebraic number field containing the "n"th roots of unity then where the product is over the finite and infinite primes "p" of the number field, and where (,) is the Hilbert symbol of the completion at "p". Hilbert's