a generalization of a jacobson’s commutativity theorem

A GENERALIZATION OF A JACOBSON’S COMMUTATIVITY THEOREM

In this paper we study the structure and the commutativity of a ring R, in which for each x,y ? R, there exist two integers depending on x,y such that [x,y]k equals x n or y n.

a generalization of strong causality

در این رساله t_n - علیت قوی تعریف می شود. این رده ها در جدول علیت فضا- زمان بین علیت پایدار و علیت قوی قرار دارند. یک قضیه برای رده بندی آنها ثابت می شود و t_n- علیت قوی با رده های علی کارتر مقایسه می شود. همچنین ثابت می شود که علیت فشرده پایدار از t_n - علیت قوی نتیجه می شود. بعلاوه به بررسی رابطه نظریه دامنه ها با نسبیت عام می پردازیم و ثابت می کنیم که نوع خاصی از فضا- زمان های علی پایدار, ب...

A generalization of Martindale's theorem to $(alpha, beta)-$homomorphism

Martindale proved that under some conditions every multiplicative isomorphism between two rings is additive. In this paper, we extend this theorem to a larger class of mappings and conclude that every multiplicative $(alpha, beta)-$derivation is additive.

A Commutativity Theorem for Associative Rings

Let m > 1; s 1 be xed positive integers, and let R be a ring with unity 1 in which for every x in R there exist integers p = p(x) 0; q = q(x) 0;n = n(x) 0; r = r(x) 0 such that either x p x n ; y]x q = x r x; y m ]y s or x p x n ;y]x q = y s x; y m ]x r for all y 2 R. In the present paper it is shown that R is commutative if it satisses the property Q(m) (i.e. for all x; y 2 R;mx; y] = 0 implie...

A Generalization of Commutativity Degree of Finite Groups

an extension and a generalization of dedekind's theorem

for any given finite abelian group‎, ‎we give factorizations of the group determinant in the group algebra of any subgroups‎. ‎the factorizations is an extension of dedekind's theorem‎. ‎the extension leads to a generalization of dedekind's theorem‎.