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You are not logged in. #1 20070827 07:04:03
Ernst LindelöfErnst Lindelöf was a Finnish mathematician. Lindelöf spaces in general topology are named after him. A Lindelöf space is a toplogical space for which every open cover has a countable subcover. A subcover of for X is a subset of which is also an open cover of X. #2 20081124 10:39:37
Re: Ernst LindelöfThough all compact spaces are Lindelöf, not all Lindelöf spaces are compact. For example, the rationals are not compact, but they are certainly Lindelöf since they are countable. In fact, any countable noncompact space is a noncompact Lindelöf space.#3 20081124 11:04:25
Re: Ernst LindelöfSo can you name a space that isn't Lindelof? "In the real world, this would be a problem. But in mathematics, we can just define a place where this problem doesn't exist. So we'll go ahead and do that now..." #4 20081125 12:30:45
Re: Ernst LindelöfLast edited by JaneFairfax (20081125 22:42:27) 