Every Unsolved Circle Problem that Sounds Easy

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  • เผยแพร่เมื่อ 21 ธ.ค. 2024

ความคิดเห็น • 45

  • @ThoughtThrill365
    @ThoughtThrill365  หลายเดือนก่อน +1

    Let me know if there's a topic you'd like me to cover next. 😊

    • @markshiman5690
      @markshiman5690 หลายเดือนก่อน

      be less repeatative and add some personality

    • @ParkerShimoda
      @ParkerShimoda หลายเดือนก่อน

      you should do every chess gambit. There are 619 of them.
      I'm pretty sure that some of your videos are either outdated (or inaccurate in a way that seems outdated, like "actually this thing was proved to be unsolvable, therefore it's solved") or don't contain everything despite claiming to (like in the cases were less than ten examples are presented. comparing to other videos, you could do more). In the second case, just change the title to reflect that (don't say "every"). In the first case, just add an apostrophe to the title (no need to address it in the thumbnail, or at all).

  • @ittaibaum3234
    @ittaibaum3234 2 หลายเดือนก่อน +20

    Correction at 8:31 - a disc is only open if it does not contain any of its boundary. You can have sets that are neither open nor closed

    • @ParkerShimoda
      @ParkerShimoda หลายเดือนก่อน

      ?

    • @crimsonsapphire6680
      @crimsonsapphire6680 หลายเดือนก่อน

      indeed, you can also have sets that are both closed and open

  • @DallasCrane
    @DallasCrane หลายเดือนก่อน +8

    Erdős-Oler Conjecture just means I can sneak a donut from every triangular donut box without anybody knowing

  • @jespersahnerpedersen
    @jespersahnerpedersen 2 หลายเดือนก่อน +3

    What is the largest number n such that any n points on the plane can be covered by disjoint unit circles? Unsolved. For n=10 there's an elegant proof, so n is greater than 10. For n=60 a pattern of 60 points can be constructed in a triangular lattice that cannot be covered by disjoint unit circles, so n is less than 60.

  • @СВЭП-и4ф
    @СВЭП-и4ф 2 หลายเดือนก่อน +13

    I was shocked that counting points on grid inside circle r is unsolved problem!

    • @lonestarr1490
      @lonestarr1490 2 หลายเดือนก่อน +5

      It kinda makes sense that that's a hard problem. Basically, you have to keep track of the distances of lattice points from the origin. But calculating these distances for a certain "layer" of lattice points based off of the distances of the previous layers only, is quite complicated.
      The lattice simply isn't a radial configuration. So the Euclidean distance isn't quite the right tool for it. There are other notions of distance that work way better, but sadly circles in Euclidean geometry only care about Euclidean distances. It's like trying to screw in slotted-head screws when all you have is a cross-head screwdriver.

    • @SubaruStaffan
      @SubaruStaffan 2 หลายเดือนก่อน +1

      @@lonestarr1490 Is this really unsolved? If you have the equation for half a circle, like \sqrt{r^2 - x^2}, you could than proceed to count the height(y) for every integer(x) on the radius (remove the decimals) and sum them together. then double them. Then add the dots on the zero line. Isnt there a mathematical way to write this? Doesnt that count as solved? I know there is at least an mathematical way to write sum (like a for loop). In latex its written as \sum_{i=1}^{n} a_i

    • @whyuclick8557
      @whyuclick8557 หลายเดือนก่อน

      @@SubaruStaffanyou might have figured it out (I have no idea what you just said)

    • @devd_rx
      @devd_rx หลายเดือนก่อน

      ​@@SubaruStaffani would assume its a closed formula which is unsolved for. i recently coded this up for my ICPC problem and it worked well till 1e18

    • @SubaruStaffan
      @SubaruStaffan หลายเดือนก่อน

      @devd_rx whats the meaning of a closed formula, and why isnt what I wrote approved? :)

  • @kent631420
    @kent631420 2 หลายเดือนก่อน +12

    Flower from BFDI in the thumbnail 🔥🔥🔥‼‼

    • @isavenewspapers8890
      @isavenewspapers8890 2 หลายเดือนก่อน

      Looks like she's grown an extra petal.

    • @FlamingSpiral20
      @FlamingSpiral20 หลายเดือนก่อน

      What do you mean? I don’t even watch the show, and I still know that Flower has 5 petals, not 6.

    • @kent631420
      @kent631420 หลายเดือนก่อน +3

      @@FlamingSpiral20 whatever, close enough 😐

  • @DavidSmith-cr7mb
    @DavidSmith-cr7mb 2 หลายเดือนก่อน +5

    for circle packing, cant you use regular polygon meshes, like squares around triangles, and oth tessellations, to predict and pinpoint the centerpoints of non-regular circle packings?

    • @DavidSmith-cr7mb
      @DavidSmith-cr7mb 2 หลายเดือนก่อน +2

      so you only need to find all regular polygon tessellations in order to also solve for all possible uniform packings with non regular disks/circles?

  • @marcelob.5300
    @marcelob.5300 2 หลายเดือนก่อน +5

    Fascinating! Thanks!

  • @jatarokemuri4549
    @jatarokemuri4549 หลายเดือนก่อน +4

    ill let you know that my kissing number is 0

  • @DadicekCz
    @DadicekCz หลายเดือนก่อน

    Am i missing something about the binary disk packing problem? You can have the ratio approach 0 (1 disk has some size and the second one's size approaches 0, therefore the packing approaching perfection)

    • @isavenewspapers8890
      @isavenewspapers8890 หลายเดือนก่อน

      I mean, it's immediately pretty obvious that this isn't the optimal packing. Instead of having those smaller disks shrink down infinitesimally, there are some clear gaps between the larger disks that you could fill with the smaller ones, achieving a better packing. In fact, the video even explicitly points out at 6:58 that the uniform packing is worse than several of the binary packings.

  • @DarthVader-ch4um
    @DarthVader-ch4um 2 หลายเดือนก่อน

    Awesome video, I am wondering how can the first conjecture not be solved yet though!

  • @AllYourMemeAreBelongToUs
    @AllYourMemeAreBelongToUs 2 หลายเดือนก่อน +2

    1:14 Empty sum

  • @jwy4264
    @jwy4264 2 หลายเดือนก่อน

    3:34 USA tst 2018 P6!

  • @marian20012
    @marian20012 หลายเดือนก่อน +1

    kissing number in higher dimensions - if we say 4th dimension's kn is 24, then by that logic, the kn for 5th dimension should be 48...6thD kn - 96...and so and so...easy math.

    • @kokiczdrzewny
      @kokiczdrzewny หลายเดือนก่อน +1

      except it is not like that

    • @marian20012
      @marian20012 หลายเดือนก่อน +1

      @@kokiczdrzewny except you can't prove me wrong...mostly because common public didn't solve how to represent higher dimensions in graphs easily to understand...I did, therefore I say - it's just doubled.

    • @kokiczdrzewny
      @kokiczdrzewny หลายเดือนก่อน +1

      @marian20012 except that the kissing number for the 5th dimension is in range of 40-44
      so how can it be 48

    • @marian20012
      @marian20012 หลายเดือนก่อน

      @@kokiczdrzewny it can be 48 as same as it it 6 for 2D and 12 for 3D. the main issue is - mathematicians make things unnecessary complicated and then they have problem to work with their overcomplicated construct. remember mathematicians who came with easier ways to solve "unsolvable" construct.

    • @kokiczdrzewny
      @kokiczdrzewny หลายเดือนก่อน +1

      @marian20012 the kn for the 1st dimension is 2
      and last time i checked 6 isnt double of 2
      so your function would just go
      2, 6, 12, 24, 48, 96 and so on
      with that random 2 at the start
      do you really think mathematicians are that stupid to get so many possible ranges in many dimensions only for a simple "double the number" function to work for all of them?

  • @GL4873-r3r
    @GL4873-r3r 2 หลายเดือนก่อน +1

    Flower from bfdi!!!!

  • @MaxPower-vg4vr
    @MaxPower-vg4vr 2 หลายเดือนก่อน +1

    The Paradox of the Circular Plane
    Contradictory:
    In Euclidean Plane Geometry, defining a circle as the set of points equidistant from a center point is paradoxically circular:
    C = {(x,y) : sqrt((x-a)^2 + (y-b)^2) = r} (Circle of radius r)
    This defines C using the algebraic distance function invoking C itself.
    Non-Contradictory:
    Infinitesimal Pluritopic Homotopy Theory
    C = {p : ∃q ∈ S1, p =r q} (Circle as monadic group quotient)
    Tπ = ⨀p ⨂q Γp,q(r) (Winding homotopy over relations)
    Defining circles C topologically as quotients of the monadic group S1 by pluralistic infinitesimal monadic relations Γp,q avoids circularity using homotopic methods.

    • @knedl9796
      @knedl9796 2 หลายเดือนก่อน +3

      No, there's nothing circular about defining a circle using Euclidean distance. The definition of this distance simply relies on the Pythagorean theorem, which doesn't include any circles.

    • @lonestarr1490
      @lonestarr1490 2 หลายเดือนก่อน +2

      ​@@knedl9796 Thank you. For I moment I thought I'm dumb.
      I got a point x in 2D space and I got a positive real number r. What prevents me from considering the set of all points of Euclidean distance r from x?

  • @jazzabighits4473
    @jazzabighits4473 หลายเดือนก่อน

    That last problem didn't sound easy at all