In this paper, we study certain curvature conditions satisfying by the conharmonic curvature tensor in a Lorentzian para-Sasakian manifold with respect to the quarter-symmetric metric connection. AMS Mathematics Subject Classification (2010): 53B05, 53C25

It is proved that the free product state, in the reduced free product of C–algebras, is faithful if the states one started with are faithful. The reduced free product of C–algebras was introduced by Voiculescu as the appropriate construction for C–algebras in the setting of his theory of freeness [1]. (See also the book [2]). Given a set I and for each ι ∈ I a unital C–algebra Aι with a state φ...

We present in this paper some fundamental tools for developing matrix analysis over the complex quaternion algebra. As applications, we consider generalized inverses, eigenvalues and eigenvectors, similarity, determinants of complex quaternion matrices, and so on. AMS Mathematics Subject Classification: 15A06; 15A24; 15A33

In this paper we recall some results concerning an application of the sum of linear operators in the infinite matrix theory. Then, we give several extensions of these results in order to obtain new properties of infinite linear systems. AMS Mathematics Subject Classification (2000): 46A15, 35A35

The modified Colombeau’s space Gt is used as the frame for solving convolution equations via Fourier transformation and division. AMS Mathematics Subject Classification (2000): 46F10

In this paper, we introduce and investigate an interesting subclass B Σ of analytic and bi-univalent functions in the open unit disk U. For functions belonging to the class B Σ we obtain estimates on the first two Taylor-Maclaurin coefficients |a2| and |a3|. The results presented in this paper would generalize and improve some recent work of Brannan and Taha [1]. AMS Mathematics Subject Classif...

We have studied some geometric properties of conharmonically flat Sasakian manifold and an Einstein-Sasakian manifold satisfying R(X, Y ).N = 0. We have also obtained some results on special weakly Ricci symmetric Sasakian manifold and have shown that it is an Einstein manifold. AMS Mathematics Subject Classification (2000): 53C21, 53C25

A b s t r a c t. Let Wp,q be the Fourier modulation space FMp,q and let ∗σ be the twisted convolution. If a ∈ D′ such that (a ∗σ φ,φ) ≥ 0 for every φ ∈ C∞ 0 , and χ ∈ S such that χ(0) 6= 0, then we prove that χa ∈ Wp,∞ iff a ∈ Wp,∞. We also present some extensions to the case when weighted Fourier modulation spaces are used. AMS Mathematics Subject Classification (2000): 47B65, 35A21, 35S05

The first derivative of the determinant function is given by the well-known Jacobi’s formula. We obtain three different expressions for all higher order derivatives. Norms of these derivatives are then evaluated exactly. AMS Subject Classifications : 15A15, 15A60, 15A69.

We investigate convergence properties in weighted spaces of distributions D′ Lp and their test spaces DLq , 1 p + 1 q = 1. Also we give characterization of weak limits of weakly convergent sequences of L-distributions. AMS Mathematics Subject Classification (2010): 46F05