`sin^2x + cos^2x = 1`
`y = frac (-b +- sqrt(b^2 - 4ac)) (2a)`
`(x + 2)^2 + (y - 3)^2 = 16`
`slope = m = frac (\text(change in y)) (\text(change in x)) = frac (Deltay) (Deltax)`

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Interesting and Fun Math Articles

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( Feb-28-2025)

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Feature Column


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Feature Column


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( May-01-2025)

We would like to clear out every room over time, but asking guests to leave seems rude. Instead, every day we assign them new rooms using a monotone increasing function… Primitive Recursion and the Disappearing Guests Bevin Maultsby NC State University Hilbert’s Hotel is a well-known thought experiment which challenges... Read more


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( Apr-01-2025)

We’ve seen that semialgebraic Teddy and semialgebraic Lambkin are both images of a four-dimensional ball. Could they be images of each other? The Teddy-Lambkin Theorem Ursula Whitcher Mathematical Reviews (AMS) My given name means bear—it’s the same root as the constellation Ursa Major—so growing up I had a huge collection... Read more


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( Mar-01-2025)

If we were working with low dosages and using the correlation between dosage and outcomes as our metric of assessing effectiveness, we might underestimate how well the drug is actually working... Footnote Finding When Correlation and Regression Slopes Tell (Slightly) Different Stories Sara Stoudt Bucknell University I recently read Robert... Read more


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( Feb-01-2025)

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The problem is similar to search problems in theoretical computer science, where the goal is to systematically locate a hidden target (in this case, the rabbit)... Capturing the Invisible Hopping Rabbit Sunil Chebolu Illinois State University Deepayan Sarkar Indian Statistical Institute A Rabbit Hunting Problem Imagine an invisible rabbit that... Read more

Joel David Hamkins

mathematics and philosophy of the infinite

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( May-12-2025)

This will be an online talk for the Leeds Set Theory Seminar, 21 May 2025 1pm BST. Contact the organizers (Hope Duncan) for Teams access. Abstract: One can find in the philosophical research literature surrounding Skolem’s paradox a certain claim, referred to … Continue reading ... Read more


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I was interviewed by Cody Roux for The Church of Logic podcast—a fascinating sweeping conversation on issues in the philosophy of mathematics and set theory, including what I described as a fundamental dichotomy between two perspectives on the nature of … Continue reading ... Read more


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( Apr-06-2025)

This will be a talk for the conference on Ultrafinitism: Physics, Mathematics, and Philosophy at Columbia University in New York, April 11-13, 2025. Abstract. I shall argue in various respects that ultrafinitism is fruitfully understood from a potentialist perspective, an … Continue reading ... Read more


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( Apr-06-2025)

 This will be a talk for the Logic Seminar at the Mathematical Institute of the University of Oxford, 29 May 2025 5pm Andrew Wiles Building. Abstract. For a given computably enumerable set $W$, consider the spectrum of assertions of the … Continue reading ... Read more


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( Mar-06-2025)

This will be a talk for the Panglobal Algebra and Logic seminar at the University of Colorado Boulder, March 12, 2025, 3:30pm MDT The talk will be available live on Zoom. Contact the organizers for access. Abstract. I shall introduce … Continue reading ... Read more


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I am honored to be giving the 2025 William Reinhardt Memorial Lecture at the University of Colorado Boulder, March 11, 2025. How we might have taken the Continuum Hypothesis as a fundamental axiom, necessary for mathematics Abstract. I shall describe … Continue reading ... Read more