Recently, Rahimi et al. [Comp. Appl. Math. 2013, In press] defined the concept of quadrupled fied point in K-metric spaces and proved several quadrupled fixed point theorems for solid cones on K-metric spaces. In this paper some quadrupled fixed point results for T-contraction on K-metric spaces without normality condition are proved. Obtained results extend and generalize well-known comparable...

We show that noncommutative differential forms on k[x], k a field, are of the form Ω1 = kλ[x] where kλ ⊇ k is a field extension. We compute the case C ⊃ R explicitly, where Ω1 is 2-dimensional. We study the induced quantum de Rahm complex Ω and its cohomology associated to a field extension, as well as gauge theory.

Let K/k be a finite extension of a global field. Such an extension can be generated over k by a single element. The aim of this article is to prove the existence of a ”small“ generator in the function field case. This answers the function field version of a question of Ruppert on small generators of number fields.

Let K/k be a finite extension of a global field. Such an extension can be generated over k by a single element. The aim of this article is to prove the existence of a ”small” generator in the function field case. This answers the function field version of a question of Ruppert on small generators of number fields.

We discuss those classes K of relational structures closed under unions that are de…ned by excluding certain …nite structures. We characterize such classes and show they contain an in…nite family of pair-wise non-embeddable members. We investigate structures in K satisfying extension conditions and construct universal structures in K satisfying only …nitely many of the extension conditions.