The style is off-putting, though. We'll see if the mathematics holds up (which would be great), but the introduction gives me pause.
Sep 6, 2020 • 21 tweets • 5 min read
Is √17 irrational?
A thread
I learned recently of a cute, apparently open, problem that I think is interesting and merits some mention.
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The standard even-odd proof of the irrationality of √2 goes as follows: Suppose p/q=√2, where p,q are positive integers. We may further assume that they are relatively prime. We have p^2=2 q^2, and a brief analysis by cases shows that both p,q should be even, contradiction.
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Aug 16, 2020 • 34 tweets • 8 min read
Kenneth Kunen, a thread.
"The real line in elementary submodels of set theory" appeared in The Journal of Symbolic Logic 65 (2000), no. 2, 683–691. doi.org/10.2307/2586561
This fun paper was written by Ken and Frank Tall. It appeared while I was in grad school. 1/
I remember it because of the title of the first draft Ken posted on his page: "What I did this summer."
I only interacted with him very briefly, but his good humor was always apparent.
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