The Metrization Problem for Fréchet Groups

نویسندگان

  • STEVO TODORCEVIC
  • JUSTIN TATCH MOORE
چکیده

In this article, we will be interested in the extent to which the assumption of first countability in this theorem can be weakened. Recall that a Hausdorff topological space X is Fréchet if whenever x is a limit point of A ⊆ X, there is a sequence an (n < ω) of elements of A which converges to x. This is a natural weakening of first countability which has been extensively studied in the literature. It turns out that this property by itself is not sufficient to ensure the metrizability of a topological group.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Weak Bases and Metrization

Several weak base (in the sense of A. V. Arhangel'skiT) metrization theorems are established, including a weak base generalization of the Nagata-Smirnov Metrization Theorem.

متن کامل

A Model with No Strongly Separable Almost Disjoint Families

We answer a question of Shelah and Steprāns [6] by producing a model of ZFC where there are no strongly separable almost disjoint families. The notion of a strongly separable almost disjoint family is a natural variation on the well known notion of a completely separable almost disjoint family, and is closely related to the metrization problem for countable Fréchet groups.

متن کامل

Some Characterizations of Developable Spaces

Two characterizations of developable spaces are proved which may be viewed as analogues, for developable spaces, of the Nagata-Smirnov metrization theorem or of the "double sequence metrization theorem " of Nagata respectively.

متن کامل

A Convexity Structure Admits but One Real Linearization of Dimension Greater than One

If V is a vector space over an ordered field F and has algebraic operations + and o, these algebraic operations determine which subsets of V are convex. Now consider a set V with no algebraic structure, but with a convexity structure, that is, a family # of subsets of V which are closed under intersection. The determination of a linear structure (F, +, o) for V which makes V a vector space over...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2006