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A Characterization of One-Element p-Bases of Rings of Constants

Piotr Jędrzejewicz (2011)

Bulletin of the Polish Academy of Sciences. Mathematics

Let K be a unique factorization domain of characteristic p > 0, and let f ∈ K[x₁,...,xₙ] be a polynomial not lying in K [ x p , . . . , x p ] . We prove that K [ x p , . . . , x p , f ] is the ring of constants of a K-derivation of K[x₁,...,xₙ] if and only if all the partial derivatives of f are relatively prime. The proof is based on a generalization of Freudenburg’s lemma to the case of polynomials over a unique factorization domain of arbitrary characteristic.

A characterization of p-bases of rings of constants

Piotr Jędrzejewicz (2013)

Open Mathematics

We obtain two equivalent conditions for m polynomials in n variables to form a p-basis of a ring of constants of some polynomial K-derivation, where K is a unique factorization domain of characteristic p > 0. One of these conditions involves Jacobians while the other some properties of factors. In the case m = n this extends the known theorem of Nousiainen, and we obtain a new formulation of the Jacobian conjecture in positive characteristic.

A note on characterizations of rings of constants with respect to derivations

Piotr Jędrzejewicz (2004)

Colloquium Mathematicae

Let A be a commutative algebra without zero divisors over a field k. If A is finitely generated over k, then there exist well known characterizations of all k-subalgebras of A which are rings of constants with respect to k-derivations of A. We show that these characterizations are not valid in the case when the algebra A is not finitely generated over k.

A Note on Elementary Derivations

Khoury, Joseph (2004)

Serdica Mathematical Journal

2000 Mathematics Subject Classification: Primary: 14R10. Secondary: 14R20, 13N15.Let R be a UFD containing a field of characteristic 0, and Bm = R[Y1, . . . , Ym] be a polynomial ring over R. It was conjectured in [5] that if D is an R-elementary monomial derivation of B3 such that ker D is a finitely generated R-algebra then the generators of ker D can be chosen to be linear in the Yi ’s. In this paper, we prove that this does not hold for B4. We also investigate R-elementary derivations D of Bm...

A note on rings of constants of derivations in integral domains

Piotr Jędrzejewicz (2011)

Colloquium Mathematicae

We observe that the characterization of rings of constants of derivations in characteristic zero as algebraically closed subrings also holds in positive characteristic after some natural adaptation. We also present a characterization of such rings in terms of maximality in some families of rings.

A note on semisimple derivations of commutative algebras

Andrzej Tyc (2005)

Colloquium Mathematicae

A concept of a slice of a semisimple derivation is introduced. Moreover, it is shown that a semisimple derivation d of a finitely generated commutative algebra A over an algebraically closed field of characteristic 0 is nothing other than an algebraic action of a torus on Max(A), and, using this, that in some cases the derivation d is linearizable or admits a maximal invariant ideal.

Affine rulings of weighted projective planes

Daniel Daigle (2001)

Annales Polonici Mathematici

It is explained that the following two problems are equivalent: (i) describing all affine rulings of any given weighted projective plane; (ii) describing all weighted-homogeneous locally nilpotent derivations of k[X,Y,Z]. Then the solution of (i) is sketched. (Outline of our joint work with Peter Russell.)

AK-invariant, some conjectures, examples and counterexamples

L. Makar-Limanov (2001)

Annales Polonici Mathematici

In my talk I am going to remind you what is the AK-invariant and give examples of its usefulness. I shall also discuss basic conjectures about this invariant and some positive and negative results related to these conjectures.

Algebraic integrability for minimum energy curves

Ivan Yudin, Fátima Silva Leite (2015)


This paper deals with integrability issues of the Euler-Lagrange equations associated to a variational problem, where the energy function depends on acceleration and drag. Although the motivation came from applications to path planning of underwater robot manipulators, the approach is rather theoretical and the main difficulties result from the fact that the power needed to push an object through a fluid increases as the cube of its speed.

An algorithm to compute the kernel of a derivation up to a certain degree

Stefan Maubach (2001)

Annales Polonici Mathematici

An algorithm is described which computes generators of the kernel of derivations on k[X₁,...,Xₙ] up to a previously given bound. For w-homogeneous derivations it is shown that if the algorithm computes a generating set for the kernel then this set is minimal.

An example of a simple derivation in two variables

Andrzej Nowicki (2008)

Colloquium Mathematicae

Let k be a field of characteristic zero. We prove that the derivation D = / x + ( y s + p x ) ( / y ) , where s ≥ 2, 0 ≠ p ∈ k, of the polynomial ring k[x,y] is simple.

Border bases and kernels of homomorphisms and of derivations

Janusz Zieliński (2010)

Open Mathematics

Border bases are an alternative to Gröbner bases. The former have several more desirable properties. In this paper some constructions and operations on border bases are presented. Namely; the case of a restriction of an ideal to a polynomial ring (in a smaller number of variables), the case of the intersection of two ideals, and the case of the kernel of a homomorphism of polynomial rings. These constructions are applied to the ideal of relations and to factorizable derivations.

De l’application des méthodes valuatives en algèbre différentielle

Guillaume Duval (2008)

Annales de la faculté des sciences de Toulouse Mathématiques

La théorie des valuations née des travaux des géomètres et arithméticiens du XIX ê me siècle, fit une apparition tardive et encore peu connue au XX ê me siècle en algèbre différentielle. Dans cet article, à travers les contributions de nombreux auteurs, nous présentons une synthèse des divers apports de la théorie des valuations à l’étude des équations différentielles. Nous insistons sur le caractère unificateur de la théorie des valuations en illustrant comment elles permettent de mettre en parallèle des...

Feuilletage canonique sur le fibré de Weil

Basile Guy Richard Bossoto (2010)

Colloquium Mathematicae

Let be M a smooth manifold, A a local algebra and M A a manifold of infinitely near points on M of kind A. We build the canonical foliation on M A and we show that the canonical foliation on the tangent bundle TM is the foliation defined by its canonical field.

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