10-327/Classnotes for Thursday September 30: Difference between revisions

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[http://katlas.math.toronto.edu/drorbn/images/f/f3/10-327-lec06p05.jpg Lecture 6 page 5]
[http://katlas.math.toronto.edu/drorbn/images/f/f3/10-327-lec06p05.jpg Lecture 6 page 5]



[[User:D|D]] 12:48, 2 October 2010 (EDT) finite Hausdorff space: The only topology satisfying Hausdorff for a finite set A is the discrete topology; for each distinct point x and y in A, {x} and {y} are disjoint. Also, every finite point set in A is closed. We can check that using the discrete metric on A (d(x,y) = 1 if x =/= y, d(x,y) = 0 if x=y), a sequence of points in A can converge to only one point at most. Also note that Hausdorff condition is stronger than T1.

Revision as of 11:48, 2 October 2010

Some blackboard shots are at BBS/10_327-100930-143624.jpg.

Dror's notes above / Student's notes below

Here are some lecture notes..

Lecture 6 page 1

Lecture 6 page 2

Lecture 6 page 3

Lecture 6 page 4

Lecture 6 page 5


D 12:48, 2 October 2010 (EDT) finite Hausdorff space: The only topology satisfying Hausdorff for a finite set A is the discrete topology; for each distinct point x and y in A, {x} and {y} are disjoint. Also, every finite point set in A is closed. We can check that using the discrete metric on A (d(x,y) = 1 if x =/= y, d(x,y) = 0 if x=y), a sequence of points in A can converge to only one point at most. Also note that Hausdorff condition is stronger than T1.