English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

Among the classical variants of the Pr\"ufer surface, some are homotopyequivalent to a CW-complex (namely, a point or a wedge of a continuum ofcircles) and some are not. The obstruction comes from the existence ofuncountably many `infinitesimal bridges' linking two metrizable opensubsurfaces inside the surface. We show that any non-metrizable surface thatpossesses such a system of infinitesimal bridges cannot be homotopy equivalentto a CW-complex. More than for the result on its own, we were motivated bytrying to blend elementary techniques of algebraic and set-theoretic topology.

Some steps on short bridges: Non-metrizable surfaces and CW-complexes