primitive element

English

Noun

primitive element (plural primitive elements)

  1. (algebra, field theory) An element that generates a simple extension.
    • 2009, Henning Stichtenoth, Algebraic Function Fields and Codes, 2nd edition, Springer, page 330:
      An algebraic extension L/K is called simple if L=K(α) for some α∈L. The element α is called a primitive element for L/K. Every finite separable algebraic field extension is simple.
      Suppose that L=K(α1,…αr) is a finite separable extension and K0⊆K is an infinite subset of K. Then there exists a primitive element α of the form α=∑i=1rciαi with ci∈K0.
  2. (algebra, field theory, of a finite field) An element that generates the multiplicative group of a given Galois field (finite field).
    • 1996, J. J. Spilker, Jr. Chapter 3: GPS Signal Structure and Theoretical Performance, Bradford W. Parkinson, James J. Spilker (editors), Global Positioning System: Theory and Applications, Volume 1, AIAA, page 114,
      Likewise, α2n=α, etc., namely, the elements are all expressed as powers of α and because α2n−1=1, α is termed a primitive element of GF(2n). […]
      Furthermore, if the irreducible polynomial has a primitive element α (where α2n−1=1) that is a root, then the polynomial is termed a primitive polynomial and corresponds to the polynomial for a maximal length feedback shift register.
    • 2003, Soonhak Kwon, Chang Hoon Kim, Chun Pyu Hong, Efficient Exponentiation for a Class of Finite Fields GF(2n) Determined by Gauss Periods, Colin D. Walter, Çetin K. Koç, Christof Paar (editors), Cryptographic Hardware and Embedded Systems, CHES 2003: 5th International Workshop, Proceedings, Springer, LNCS 2779, page 228,
      Also in the case of a Gauss period of type (n,1), i.e. a type I optimal normal element, we find a primitive element in GF(2n) which is a sparse polynomial of a type I optimal normal element and we propose a fast exponentiation algorithm which is applicable for both software and hardware purposes.
    • 2008, Stephen D. Cohen, Mateja Preśern, The Hansen-Mullen Primitivity Comjecture: Completion of Proof, James McKee, James Fraser McKee, Chris Smyth (editors, Number Theory and Polynomials, Cambridge University Press, page 89,
      For q a power of a prime p, let 𝔽q be the finite field of order q. Its multiplicative group 𝔽q∗ is cyclic of order q−1 and a generator of 𝔽q∗ is called a primitive element of Fq. More generally, a primitive element γ of Fqn, the unique extension of degree n of 𝔽q, is the root of a (necessarily monic and automatically irreducible) primitive polynomial f(x)∈𝔽q[x] of degree n.
      […]
      Here, necessarily, c must be a primitive element of 𝔽q, since this is the norm of a root of the polynomial.
  3. (number theory) Given a modulus n, a number g such that every number coprime to n is congruent (modulo n) to some power of g; equivalently, a generator of the multiplicative field of integers modulo n.
    • 1972, W. Wesley Peterson; E. J. Weldon, Jr., Error-correcting Codes, 2nd edition, The MIT Press, page 457:
      Let A be a prime number for which 2 is a primitive element. Then 2A−1−1 is divisible by A.
  4. (algebra, lattice theory, of a lattice) An element that is not a positive integer multiple of another element of the lattice.
    • 1985, Revista Matemática Iberoamericana, Volume 1, Real Sociedad Matemática Española, page 111:
      But suppose L′∈Cν(S0) so that det⁡(L′)=η′π▸0 for some totally positive unit η′ and so that L′ is everywhere locally a primitive element of the 𝔬-lattice Rν.
  5. (algebra, of a coalgebra over an element g) An element x ∈ C such that μ(x) = x ⊗ g + g ⊗ x, where μ is the comultiplication and g is an element that maps to the multiplicative identity 1 of the base field under the counit (in particular, if C is a bialgebra, g = 1).
    • 2009, Masoud Khalkhali, Basic Noncommutative Geometry, European Mathematical Society, page 29,
      A primitive element of a Hopf algebra is an element h∈H such that
      Δh=1⊗h+h⊗1.
      It is easily seen that the bracket [x,y]:=xy−yx of two primitive elements is again a primitive element. It follows that primitive elements form a Lie algebra. For H=U(𝔤) any element of 𝔤 is primitive and in fact using the Poincaré-Birkhoff-Win theorem, one can show that the set of primitive elements of U(𝔤) coincides with the Lie algebra 𝔤.
  6. (group theory, of a free group) An element of a free generating set of a given free group.
    • 2004, Dmitry Y. Bormotov, “Experimenting with Primitive Elements in F2”, in Alexandre Borovik, Alexei G. Myasnikov, editors, Computational and Experimental Group Theory: AMS-ASL Joint Special Session, American Mathematical Society, page 215:
      In this paper we apply regression models and other pattern recognition techniques to the task of classifying primitive elements of a free group.

Usage notes

Synonyms

  • (number theory): primitive root
  • (element that generates a field extension): generating element
  • (element that generates the multiplicative group of a finite field): primitive root of unity

Translations

Further reading