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Alex Kontorovich
11K posts
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Alex Kontorovich
@AlexKontorovich
Mathematician (Distinguished Professor of #Math at @RutgersU). Here to learn about research, education, and community. Let’s build something together.
math.rutgers.edu/~alexk
Joined November 2018
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  • Pinned
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    Alex Kontorovich
    @AlexKontorovich
    Sep 23, 2019
    Collecting here a meta-thread of threads.
  • user avatar
    Alex Kontorovich
    @AlexKontorovich
    Mar 6, 2020
    With Pi Day just around the corner, let’s remember what Pi is all about. After washing your hands thoroughly, cut the crust off a pizza pie and lay it across four others. You’ll see that the crust spans a little more than 3 pies. That’s Pi ≈ 3.14. But that’s not all! (Cont’d)
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    Alex Kontorovich
    @AlexKontorovich
    Sep 28, 2023
    An aspiring mathematician asked me recently how I spend my time. I asked if he liked video games; he said yes. I said: imagine being paid to play the hardest games you can find, all day long, and taking breaks to teach others how to play simpler levels. Every now and then, go …
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    PHD Comics
    @PHDcomics
    Sep 28, 2023
    How profs spend their time
    1.4M
  • user avatar
    Alex Kontorovich
    @AlexKontorovich
    Apr 23, 2025
    Piano teacher: "Your son is playing too much at home, please have him practice less; what's the rush?" Soccer coach: "Your son is dribbling too much at home, please have him practice less; what's the rush?" Math teacher: "Your son is learning too much math at home, please slow
    242K
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    Alex Kontorovich
    @AlexKontorovich
    Apr 7, 2024
    The remaining 2% will be emailing me their solutions once a week for the rest their lives…
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    Howie Hua
    @howie_hua
    Apr 7, 2024
    98% of people can't solve this!
    "Cross each bridge exactly once!" with the 7 bridges of Konigsberg.
    1.5M
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    Alex Kontorovich
    @AlexKontorovich
    Apr 11, 2022
    How old were you when you learned that the perfect figure 8 (or infinity) is simply the inversion through a circle of a hyperbola?? 🤯
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    Alex Kontorovich
    @AlexKontorovich
    Jan 11, 2021
    Claim: 10+10 = 11+11 Proof: 10+10 = twenty 11+11 = twenty too . . Sorry. Dad joke.
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    Alex Kontorovich
    @AlexKontorovich
    Nov 6, 2025
    Whoever hasn't seen this documentary is missing out on what was possibly the greatest mathematical event of the 20th century...
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    Fermat's Library
    @fermatslibrary
    Nov 5, 2025
    Andrew Wiles on the morning he discovered how to fix his proof of Fermat's Last Theorem
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    95K
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    Alex Kontorovich
    @AlexKontorovich
    Mar 26, 2023
    Awesome @MoMath1 presentation on the discovery of the Hat! A summary 🧵: This is Dave Smith, a mathematical artist. He spends *a lot* of time just messing around, seeing what shapes he can tile in usual ways. Nov 20, 2022, he emails @cs_kaplan to say: he can't figure out...
    499K
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    Alex Kontorovich
    @AlexKontorovich
    Sep 8, 2023
    The 19th century was a *crazy* time in math. In fact, our first year grad courses (Real, Complex, and Algebra) are all the result of people breaking math in the 1800s and needing to figure out how to fix it! E.g. we have Algebra because Lamé claimed a proof of FLT using …
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    Cliff Pickover
    @pickover
    Sep 7, 2023
    Don't you just love the Weierstrass function? "In mathematics, the Weierstrass function is an example of a real-valued function that is continuous everywhere but differentiable nowhere. It is an example of a fractal curve. It is named after its discoverer Karl Weierstrass."
    298K
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    Alex Kontorovich
    @AlexKontorovich
    Nov 20, 2019
    Take a bunch of your favorite polyhedra and plot them in R^3 at coordinates (#vertices,#edges,#faces). Notice anything? What's the equation of this plane? :)
    GIF
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    Alex Kontorovich
    @AlexKontorovich
    Feb 3, 2025
    “Number Theory” sounds so mundane, whereas “Topology” is so mysterious; we should rebrand Number Theory as Arithmology.
    63K
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    Alex Kontorovich
    @AlexKontorovich
    May 8, 2025
    We mathematicians have a 50 year head start on this issue! "Why should I learn my times tables when my pocket calculator can do it for me?" It's pretty simple: feel free not to; you'll pay dearly for it later. Same 20 years ago with Calc 1 ["Mathematica can compute this
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    Tim Urban
    @waitbutwhy
    May 7, 2025
    Yup. Assignments should be like “use AI to do ___ complex project” and then have an oral component where the student explains each step of the process they used and their thought process behind it. Schools should prepare kids to accomplish things with the tools of their world.
    105K
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    Alex Kontorovich
    @AlexKontorovich
    Oct 10, 2024
    Had an interesting discussion offline about whether posting all my lectures to YouTube for free diminishes the value of the experience for students paying tuition at Rutgers (or this semester, Princeton). I claim it does not. Those students are paying for the opportunity to
    84K

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