Gravitational decoupled anisotropic solutions in $$f({\mathcal {G}})$$ f ( G ) gravity

f-DERIVATIONS AND (f; g)-DERIVATIONS OF MV -ALGEBRAS

Recently, the algebraic theory of MV -algebras is intensively studied. In this paper, we extend the concept of derivation of $MV$-algebras and we give someillustrative examples. Moreover, as a generalization of derivations of $MV$ -algebraswe introduce the notion of $f$-derivations and $(f; g)$-derivations of $MV$-algebras.Also, we investigate some properties of them.

(f) pinch (g)

F P M G

In group theory, it is a fundamental question to determine what information about a group is necessary and sufficient tomake a group finitely presented. In this paper, we develop the theory of Σ-invariants due to Robert Bieri and Ralph Strebel [Bieri] whi provides an answer to this question for the class of metabelian groups. We begin our study of Σ-invariants with a digression on group extens...

G-positive and G-repositive solutions to some adjointable operator equations over Hilbert C^{∗}-modules

Some necessary and sufficient conditions are given for the existence of a G-positive (G-repositive) solution to adjointable operator equations $AX=C,AXA^{left( astright) }=C$ and $AXB=C$ over Hilbert $C^{ast}$-modules, respectively. Moreover, the expressions of these general G-positive (G-repositive) solutions are also derived. Some of the findings of this paper extend some known results in the...

G+++ and Brane Solutions

We demonstrate that the very extended G group element of the form gA = exp(− 1 (β,β) lnNβ ·H) exp((1−N)Eβ) describes the usual BPS, electric, single brane solutions found in G theories. email: [email protected] email: [email protected]