De-Naming the Blog

This blog was started in January 2008, a bit over eight years after I started as a professor at UVA and initiated the research group. It was named after Thomas Jefferson’s cipher wheel, which has long been (and remains) one of my favorite ways to introduce cryptography. Figuring out how to honor our history, including Jefferson’s founding of the University, and appreciate his ideals and enormous contributions, while confronting the reality of Jefferson as a slave owner and abuser, will be a challenge and responsibility for people above my administrative rank.

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Cantor's (No Longer) Lost Proof

In preparing to cover Cantor’s proof of different infinite set cardinalities (one of my all-time favorite topics!) in our theory of computation course, I found various conflicting accounts of what Cantor originally proved. So, I figured it would be easy to search the web to find the original proof. Shockingly, at least as far as I could find1, it didn’t exist on the web! The closest I could find was in Google Books the 1892 volume of the Jähresbericht Deutsche Mathematiker-Vereinigung (which many of the references pointed to), but in fact not the first value of that journal which contains the actual proof.

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Older Posts

Older posts have not been moved into this new blog, but are still available here:

All Posts by Category or Tags.