Normalizing extensions of semiprime rings.
Let be an associative unital ring and let be a strongly nil clean element. We introduce a new idea for examining the properties of these elements. This approach allows us to generalize some results on nil clean and strongly nil clean rings. Also, using this technique many previous proofs can be significantly shortened. Some shorter proofs concerning nil clean elements in rings in general, and in matrix rings in particular, are presented, together with some generalizations of these results.
Parasemifields (i.e., commutative semirings whose multiplicative semigroups are groups) are considered in more detail. We show that if a parasemifield contains as a subparasemifield and is generated by , , as a semiring, then is (as a semiring) not finitely generated.
If is a prime ring such that is not completely reducible and the additive group is not complete, then is slender.