Let E/k be a cubic field extension and J a simple exceptional Jordan algebra of degree 3 over k. Then £ is a reducing field of J if and only if E is isomorphic to a (maximal) subfield of some isotope of /. If k has characteristic not 2 or 3 and contains the third roots of unity then every simple exceptional Jordan division algebra of degree 3 over k contains a cyclic cubic subfield. Exceptional...

Let A1,A2 be standard operator algebras on complex Banach spaces X1, X2, respectively. For k ≥ 2, let (i1, . . . , im) be a sequence with terms chosen from {1, . . . , k}, and define the generalized Jordan product T1 ◦ · · · ◦ Tk = Ti1 · · ·Tim + Tim · · ·Ti1 on elements in Ai. This includes the usual Jordan product A1 ◦ A2 = A1A2 + A2A1, and the triple {A1, A2, A3} = A1A2A3 + A3A2A1. Assume th...

Affine difference algebraic groups are a generalization of affine obtained by replacing equations with equations. We show that the isomorphism theorems from abstract group theory have meaningful analogs for these and we establish Jordan–Hölder type theorem allows us to decompose any into almost-simple groups. also characterize via

Pre-Jordan algebras were introduced recently in analogy with preLie algebras. A pre-Jordan algebra is a vector space A with a bilinear multiplication x · y such that the product x ◦ y = x · y + y · x endows A with the structure of a Jordan algebra, and the left multiplications L·(x) : y 7→ x · y define a representation of this Jordan algebra on A. Equivalently, x ·y satisfies these multilinear ...

1. Introduction. One may construct a Jordan homomorphism from one (associative) ring into another ring by taking the sum of a homo-morphism and an antihomomorphism of the first ring into two ideals in the second ring with null intersection [6]. A number of authors have considered conditions on the rings that imply that every Jordan homomorphism, or isomorphism, is of this form [6], [3], [7], [1...

Classification theory guarantees the existence of an isomorphism between any two E8’s, at least over an algebraically closed field of characteristic 0. The purpose of this paper is to construct for any Jordan algebra J of degree 3 over a field Φ of characteristic ≠ 2,3 an explicit isomorphism between the algebra obtained from J by Faulkner’s construction and the algebra obtained from the split ...

1. Endomorphisms of vector spaces Throughout these notes, k is an algebraically closed field, varieties are reduced and irreducible k-schemes of finite type, and morphisms of varieties are k-morphisms. A moduli problem for a class of algebraic objects consists in two parts: finding the equivalence classes of the objects under a suitable equivalence relation (usually isomorphism), and parametriz...

In this article, we prove an isomorphism theorem for the case of refinement $\Gamma$-monoids. Based on show a version well-known Jordan-H\"older in framework. The main article states that - as modules monoid $T$ has $\Gamma$-composition series if and only it is both $\Gamma$-Noetherian $\Gamma$-Artinian. As module theory, these two concepts can be defined via ascending descending chains respect...

(Received) We study the Weyl closure Cl(L) = K(x)h@iL \ D for an operator L of the rst Weyl algebra D = Khx;@i. We give an algorithm to compute Cl(L) and we describe its initial ideal under the order ltration. Our main application is an algorithm for constructing a Jordan-HH older series for a holonomic D-module and a formula for its length. Using the closure, we also reproduce a result of Strr...