Lectures on Klein surfaces and their fundamental group.
... C ∪ {∞} with real structure τ : z 7−→ z, whose fixed-point set is the circle RP1 = R ∪ {∞}. Another real structure on CP1 is given by τ0 : z 7−→ − z1 , which has no fixed points. These two real structures are the only possible ones on CP1 (see Exercise 1.1). Examples of real structures on compact cu ...
... C ∪ {∞} with real structure τ : z 7−→ z, whose fixed-point set is the circle RP1 = R ∪ {∞}. Another real structure on CP1 is given by τ0 : z 7−→ − z1 , which has no fixed points. These two real structures are the only possible ones on CP1 (see Exercise 1.1). Examples of real structures on compact cu ...
Ultrafilters and Independent Systems - KTIML
... Weak P-points are points in ω ∗ which are not limit points of any countable set. Obviously not every point of ω ∗ is a weak P-point, so this also gives a proof of the nonhomogeneity of ω ∗ . And it actually shows two concrete topologically distinct points (a weak P-point and a non-weak P-point) witn ...
... Weak P-points are points in ω ∗ which are not limit points of any countable set. Obviously not every point of ω ∗ is a weak P-point, so this also gives a proof of the nonhomogeneity of ω ∗ . And it actually shows two concrete topologically distinct points (a weak P-point and a non-weak P-point) witn ...
Boundary manifolds of projective hypersurfaces Daniel C. Cohen Alexander I. Suciu
... is to study the Milnor fibration f : Cℓ+1 \ {f (x) = 0} → C∗ . Of course, the different approaches are interrelated. For example, if the degree of f is n, then the Milnor fiber F = f −1 (1) is a cyclic n-fold cover of X. Consequently, knowledge of the cohomology groups of X with coefficients in cert ...
... is to study the Milnor fibration f : Cℓ+1 \ {f (x) = 0} → C∗ . Of course, the different approaches are interrelated. For example, if the degree of f is n, then the Milnor fiber F = f −1 (1) is a cyclic n-fold cover of X. Consequently, knowledge of the cohomology groups of X with coefficients in cert ...