10.04.2013 Views

1. The Baire category theorem - Aarhus Universitet

1. The Baire category theorem - Aarhus Universitet

1. The Baire category theorem - Aarhus Universitet

SHOW MORE
SHOW LESS

Create successful ePaper yourself

Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.

Basic properties the notions of <strong>category</strong><br />

(d) If h : S → S is a homeomorphism, E ⊆ S and h(E) are of the<br />

same <strong>category</strong>.<br />

It suffices to show that h(E) is of the first <strong>category</strong> if and only if E.<br />

Furthermore, since E = h −1 (h(E)), it suffice to show that h(E) is<br />

of the first <strong>category</strong> when E is.<br />

Klaus Thomsen <strong>1.</strong> <strong>The</strong> <strong>Baire</strong> <strong>category</strong> <strong>theorem</strong>

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!