Fifteen Most Famous Transcendental Numbers

(sprott.physics.wisc.edu)

43 points | by vismit2000 3 hours ago ago

17 comments

  • adrian_b a few seconds ago ago

    It should be noted that the number e = 2.71828 ... does not have any importance in practice, its value just satisfies the curiosity to know it, but there is no need to use it in any application.

    The transcendental number whose value matters is ln 2 = 0.693 ... (and the value of its inverse log2(e), in order to avoid divisions).

  • brianberns an hour ago ago

    I read this with pleasure, right up until the bit about the ants. Then I saw the note from myself at the end, which I had totally forgot writing seven years ago. I probably first encountered the article via HN back then as well. Thanks for publishing my thoughts!

  • nuancebydefault an hour ago ago

    I would have expected more numbers originating from physics, like Reynolds number (bad example since it is not really constant though).

    The human-invented ones seem to be just a grasp of dozens man can come up with.

    i to the power of i is one I never heard of but is fascinating though!

  • mg 6 minutes ago ago

    Two surprising facts about transcendental numbers:

    1: Almost all numbers are transcendental.

    2: If you could pick a real number at random, the probability of it being transcendental is 1.

    Most of our lives we deal with non-transcendental, even though those are infinitely rare.

  • barishnamazov 2 hours ago ago

    Don't want to be "that guy," but Euler's constant and Catalan's constant aren't proven to be transcendental yet.

    For context, a number is transcendental if it's not the root of any non-zero polynomial with rational coefficients. Essentially, it means the number cannot be constructed using a finite combination of integers and standard algebraic operations (addition, subtraction, multiplication, division, and integer roots). sqrt(2) is irrational but algebraic (it solves x^2 - 2 = 0); pi is transcendental.

    The reason we haven't been able to prove this for constants like Euler-Mascheroni (gamma) is that we currently lack the tools to even prove they are irrational. With numbers like e or pi, we found infinite series or continued fraction representations that allowed us to prove they cannot be expressed as a ratio of two integers.

    With gamma, we have no such "hook." It appears in many places (harmonics, gamma function derivatives), but we haven't found a relationship that forces a contradiction if we assume it is algebraic. For all we know right now, gamma could technically be a rational fraction with a denominator larger than the number of atoms in the universe, though most mathematicians would bet the house against it.

  • senfiaj 2 hours ago ago

    > Euler's constant, gamma = 0.577215 ... = lim n -> infinity > (1 + 1/2 + 1/3 + 1/4 + ... + 1/n - ln(n)) (Not proven to be transcendental, but generally believed to be by mathematicians.)

    So why bring some numbers here as transcendental if not proven?

    • auggierose 2 hours ago ago

      Because it still might be transcendental. Just because you don't know if the list is correct, doesn't mean it isn't.

      • senfiaj 2 minutes ago ago

        Yes it's "likely" to be transcendental, maybe there are some evidences that support this, but this is not a proof (keep in mind that it isn't even proven to be irrational yet). Similarly, most mathematicians/computer scientist bet that P ≠ NP, but it doesn't make it proven and no one should claim that P ≠ NP in some article just because "it's most likely to be true" (even though some empirical real life evidence supports this hypothesis).

      • loloquwowndueo an hour ago ago

        So it’s like “15 oldest actors to win an Oscar” and including someone who’s nominated this year but hasn’t actually won. But he might, right?

        No, my dudes. Just no. If it’s not proven transcendental, it’s not to be considered such.

  • zkmon 2 hours ago ago

    If a number system has a transcendental number as its base, would these numbers still be called transcendental in that number system?

    • moefh 2 hours ago ago

      Yes. A number is transcendental if it's not the root of a polynomial with integer coefficients; that's completely independent of how you represent it.

    • frutiger 2 hours ago ago

      I think the elements of the base need to be enumerable (proof needed but it feels natural), and transcendental numbers are not enumerable (proof also needed).

      • tocs3 24 minutes ago ago
      • JadeNB 22 minutes ago ago

        I think your parent comment was speaking of a "base-$\alpha$ representation", where $\alpha$ is a single transcendental number—no concerns about countability, though one must be quite careful about the "digits" in this base.

        (I'm not sure what "the elements of the base need to be enumerable" means—usually, as above, one speaks of a single base; while mixed-radix systems exist, the usual definition still has only one base per position, and only countably many positions. But the proof of countability of transcendental numbers is easy, since each is a root of a polynomial over $\mathbb Q$, there are only countably many such polynomials, and every polynomial has only finitely many roots.)