Talk:2529: Unsolved Math Problems

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Does anyone have any clue whether the writing on the board in the weirdly abstract panel means anything? Maybe add an explanation about it?162.158.227.91 13:23, 17 October 2021 (UTC)

I think it is also "ill-formed" in the sense that it is not very carefully written.

Center panel possibly related to "The drunkards walk" and theories on randomised motion. https://www.quantamagazine.org/random-walk-puzzle-solution-20160907/ More references https://mathworld.wolfram.com/RandomWalk.html

Someone's gotta point out that "walking randomly on a grid, never visiting the same square twice" would rapidly trap you in a corner (even the example has a 50/50 chance of that happening on the next move) 172.70.130.125 04:29, 16 October 2021 (UTC)

Not if it's an infinite grid.

I think there's two different ways to interpret the question - as a uniform random element of the set of all non-self-intersection NxK length paths, in which case it's fine, or as a path defined by a random walk in which moves onto your own path are not allowed, which doesn't seem well defined, since you might end up in a situation where you are surrounded by your own path and cannot continue for all NxK steps.

An early example of a cursed problem is the Cantor Function. https://en.wikipedia.org/wiki/Cantor_function

I admire whoever wrote the description of the curve in the "cursed" panel. Barmar (talk) 05:36, 16 October 2021 (UTC)

"Algebreic" is a misspelling of "algebraic". Could Randall really have made this mistake, or is it another malamanteau? What does "breic" come from? Barmar (talk) 06:10, 16 October 2021 (UTC)


I wonder if Randall was actually referring to that quote about "Into the Woods", or he just thought "Sondheim calculus" sounded cool and it was a total coincidence. I found it when I googled "sondheim calculus" to make sure it wasn't a real thing. Barmar (talk) 06:29, 16 October 2021 (UTC)

In panel 2, what would 'k' be? 172.69.35.108 08:00, 16 October 2021 (UTC)

'k' would represent the number of marbles placed on the ground. 162.158.88.127 08:09, 16 October 2021 (UTC)

Though probably correct, I think the implied state is that an integer multiple (k) of N steps is made (s=N*k), with that number of marbles dropped, not s=(N*k)+c steps (for N>c) which would have the same result (uselessly) for all values of s where c ranges 0..N-1. It just introduces inflections into the graph (with s as an axis) that needn't be there (with just a k-based one). Or, in other words, selectively poll all s-values that are exactly divisible by N, and forget all the rest. (That divisor is k, and hence k is the number of marbles. Or perhaps k+1 if you leave one on the starting spot too.) 162.158.159.25 21:59, 16 October 2021 (UTC)

To me, the cursed curve looks a bit like a crosier https://commons.wikimedia.org/wiki/File:Crosiere_of_arcbishop_Heinrich_of_Finstingen.jpg

--> I had the same impression and added it. --162.158.94.219 11:40, 16 October 2021 (UTC)

No explanation of the "Euler Field Manifold Hypergroup (Isomorphic to a)..." part?

The cursed curve looks almost like someone took a graph of the Binet formula in the complex plane, stretched it out a bit, and rotated it onto the i axis.

This was my first thought too when I saw it. 172.69.34.87 17:16, 16 October 2021 (UTC)
It looks like Vulcan script to me. LtPowers (talk) 13:51, 16 October 2021 (UTC)
That's what it looks like to me too; recognized it from that Numberphile video on Fibonacci numbers in the complex plane 108.162.245.245 07:36, 17 October 2021 (UTC)
It looks to me like someone has raised a dark spirit, which is about to manifest from a column of black smoke. 162.158.154.206 10:25, 20 October 2021 (UTC)

Could the cursed curve be a reference to the logistic map?

Can someone produce a high resolution image of the Cursed Curve? It needs to be on a T-shirt Avimimus (talk) 21:39, 16 October 2021 (UTC)

Is someone going to mention the title text?

I swear I've seen that third plot, I thought it was in XKCD, but a quick run through tagged entries didn't find anything... unfortunately I consume a lot of math media so I can't place it. It's bugging me so I hope this note will serve as encourgement to someone that DOES remember 162.158.106.221 21:29, 16 October 2021 (UTC)

I'm sure I've seen components of the cursed-curve, not sure if they fit together like that, easily, though. The differentiation of dy/dt (which is odd in itself) of the first (lower) bit looks discontinuous, followed by a chaotic oscilation (may just be the culmination of the less frenetic chaos that created the first set of x=f(y) - again, an unusual way round) that then settles into a pattern where regardless of the 'prime axis', you have multiple real roots on the other, towards some great-attractor value.
In more standard x/y (or y=f'(x)?) notation, it is clear that there are multiple real roots for various values of x within a range, and possible none at all beyond that (or it's a plotting error insofar as x tends to ±infinity it has a very narrow range of y that is never sampled properly, but should connect to that pulse 'randomness'). If it's a plot of real vs imaginary components of a complex function to a different continuous value, I suspect someone is playing silly-buggers with multiple (perhaps nested?) trigonometric functions, polynomials and variable-shifted powers. But it's nearly thirty years since I did mathematics at the level needed to disentangle this neatly (back when Mandelbrots and Julias were still a staple wall-poster for any student not more into the likes of Iron Maiden skull-motifs or <insert your favourite classic film here>, and even then it might be) so don't ask me where to start. 162.158.89.140 16:48, 17 October 2021 (UTC)

To me the curve in panel three looks like a cursed (ha) mixture of an oscillatory time responses of dynamic systems with either an Nquist plot or simply trajectories of eigenvalues (of a stable system) at the end. Links: https://en.wikipedia.org/wiki/Nyquist_stability_criterion#Nyquist_plot , https://electronicscoach.com/time-response-of-second-order-system.html https://en.wikipedia.org/wiki/Eigenvalues_and_eigenvectors Domi (talk)Domi


Are there any examples of "cursed" math problems? I've seen "weirdly abstract" and "weirdly concrete" ones, but not "cursed" ones. 162.158.63.117 01:03, 17 October 2021 (UTC)

Some functions definitely make graphs that look weird to humans for reasons that are not immediately obvious (see sin(cos(tan(xy))) = sin(cos(tan(x))) + sin(cos(tan(y))): https://www.desmos.com/calculator/mt08x3yqxj). I suppose to be cursed in the sense I take here, it would have to be unsolved as to why it looks weird to humans, which is probably not the case in my example, but I imagine there are examples. 141.101.99.92 19:41, 20 October 2021 (UTC)

The symbol in the third panel looks like an unalome, which is not a mathematical symbol but a Buddhist or mystical one https://en.wikipedia.org/wiki/Yantra_tattooing#Types_and_designs

There is at least one paper on arxiv defining quasimonoid, 1401.7748. It's from 2014 so it existed long before the comic. --162.158.88.253 14:04, 17 October 2021 (UTC)

Links, please! Not all of us are mathematicians. If you mention something that you think the cursed curve might represent, please provide a link to something describing that something so the rest of us can read it and attempt to learn more. Shamino (talk) 17:44, 17 October 2021 (UTC)

That cursed squiggle reminds me of the zeta function: https://www.johndcook.com/blog/2019/11/29/near-zeros-of-zeta/

That cursed squiggle sure looks like the sort of thing that used to flow from Saul Steinberg's pen, as seen in the pages of the New Yorker back in the 60s. The most relevant example I can find right now is from 1965: https://fineartamerica.com/featured/new-yorker-february-20th-1965-saul-steinberg.html 162.158.255.177 03:38, 18 October 2021 (UTC)

So, is the middle one an actual unsolved problem? --162.158.91.236 16:07, 18 October 2021 (UTC)

In this comic ponytail is obviously not Dr. Adams. (Discussion came up two comics ago.) --162.158.88.115 21:42, 18 October 2021 (UTC)

Is Panel #2 a real unsolved problem? It reads like one.

Adding to the first comment - should we include an explanation of the formula in the first panel as well? The denominator means "is an element of aleph-5, the fifth infinite cardinal number". The numerator is less clear; a dot over a variable usually indicates a derivative, but I haven't seen a dot over a set. Raising R (set of real numbers) to the power of Z (set of integers) refers to the set of all functions from the integers to the reals. I don't recognize the diamond with a line through the bottom or the two arrows.

Shout-out to whoever wrote the incomplete tag. 162.158.74.172 20:21, 19 October 2021 (UTC)

Is there a reason why the article uses "millennium" (correct) and "millenium" (incorrrect)?

Maybe bad spelling by one or more editors? The spelling has now been fixed where it was incorrect. Ianrbibtitlht (talk) 02:20, 21 October 2021 (UTC)

I swear I recognize the Cursed Curve as the art from the story "The Theory that Jack Built", from "The Space Child's Mother Goose", by Frederick Winsor. Haven't been able to find my copy, so still not sure. Elkern (talk) 21:35, 25 October 2021 (UTC)

In the transcript, the first 3 characters of the equation in panel 1 are showing up as basic squares for me. When I go into editing mode, I see the correct rendering of the characters in the wikitext, just not on the page itself. Don't know if this might create/indicate a problem for screen readers. I'm viewing the page on Chrome 94, in Windows 10 version 1909. Dansiman (talk) 21:12, 26 October 2021 (UTC)