I missed getting an entry into the latest Carnival of Mathematics, which went up a day early at Science and Reason. (Serves me right for procrastinating!) As usual, most of the articles are well over my head.

The carnival begins with a tribute to Field’s Medalist Paul Cohen (April 2, 1934 – March 23, 2007), the man who settled the first of the famous Hilbert Problems, the Continuum Hypothesis. Then come the math articles. Here are my favorites:

~~Formalisation and de-formalisation~~[That page has disappeared, but I think this one will work. If that link goes AWOL, too, just do a search for “Scooping the Loop Snooper” by Geoffrey K. Pullum.]

In which we find a delightful informal proof that the Halting Problem is undecidable. Wouldn’t it be fun if all math proofs could be written in Dr. Seuss-style verse?Introducing the Surreal Numbers (Edited rerun)

Which explains a method to create and represent the real numbers that I could almost convince myself I understood.The old new math

In which JD teaches his algebra class a bit of twentieth-century history. If you aren’t familiar with Jonathan’s blog, be sure to spend some time browsing his “puzzle” posts.

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