Maps on idempotents
نویسندگان
چکیده
منابع مشابه
On concentrating idempotents, a survey
A sum of exponentials of the form f(x) = exp (2 iN1x)+exp (2 iN2x)+ +exp (2 iNmx), where the Nk are distinct integers is called an idempotent trigonometric polynomial or, simply, an idempotent. It is known that for every p > 1; and every set S of the torus T = R=Z with jSj > 0; there are idempotents concentrated on S in the Lp sense. We sketch how this concentration phenomenon originated as a r...
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Let T be a triangular ring. An additive map δ from T into itself is said to be Jordan derivable at an element Z ∈ T if δ(A)B +Aδ(B) + δ(B)A+Bδ(A) = δ(AB+BA) for any A,B ∈ T with AB + BA = Z. An element Z ∈ T is called a Jordan all-derivable point of T if every additive map Jordan derivable at Z is a Jordan derivation. In this paper, we show that some idempotents in T are Jordan all-derivable po...
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On Inverse Categories with Split Idempotents
We present some special properties of inverse categories with split idempotents. First, we examine a Clifford-Leech type theorem relative to such inverse categories. The connection with right cancellative categories with pushouts is illustrated by simple examples. Finally, some basic properties of inverse categories with split idempotents and kernels are studied in terms of split idempotents wh...
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ژورنال
عنوان ژورنال: Studia Mathematica
سال: 2005
ISSN: 0039-3223,1730-6337
DOI: 10.4064/sm169-1-2