Hereditarily Unicoherent Continua and Their Absolute Retracts
نویسندگان
چکیده
منابع مشابه
Kernels of Hereditarily Unicoherent Continua and Absolute Retracts
For a hereditarily unicoherent continuum X, its kernel means the common part of all subcontinua of X that intersect all arc components of X. This concept naturally appears when absolute retracts for the class of hereditarily unicoherent continua are studied. Let Y be such an absolute retract. Among other results, we prove that (a) Y is indecomposable if and only if it is identical with its kern...
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The subgroup R of the group G has been termed a retract of the group G whenever there exists an idempotent endomorphism of G which maps G upon R. This definition is in strict analogy to the topological concept of retract. Thus one may be tempted to define absolute retracts in like similarity to topological usage. However, we shall prove in the course of the present note that the identity is the...
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ژورنال
عنوان ژورنال: Rocky Mountain Journal of Mathematics
سال: 2004
ISSN: 0035-7596
DOI: 10.1216/rmjm/1181069893