There are SIX Platonic Solids

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  • Опубликовано: 1 июл 2024
  • Meet the Hyper-Diamond! It's the sixth Platonic Solid and it only works in the fourth dimension.
    Your best google bet to find more about the hyper-diamond is "24-cell".
    mathworld.wolfram.com/24-Cell....
    Watch my Royal Institution lecture about 4D shapes:
    • Four Dimensional Maths...
    My book: makeanddo4d.com/
    Maths Gear: mathsgear.co.uk/
    4D animations made with Stella4D: www.software3d.com/Stella.php
    MATT PARKER: Stand-up Mathematician
    Website: standupmaths.com/
    Music by Howard Carter
    Design by Simon Wright
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Комментарии • 1 тыс.

  • @quacking.duck.3243
    @quacking.duck.3243 3 года назад +144

    Guys, the video by jan Misali is about *regular polyhedra,* not platonic solids. There are 5 platonic solids in 3D.

    • @LeoStaley
      @LeoStaley 3 года назад +19

      *thank you!* how can so many people be maths enthusiasts and not know this??

    • @pipolwes000
      @pipolwes000 3 года назад +20

      Matt repeatedly conflates the platonic solids in 3d with the regular polyhedra. "Despite the infinitely many 2d shapes, there's no other way to join them together to make a regular 3d shape. We only get those 5 platonic solids"

    • @LeoStaley
      @LeoStaley 3 года назад +8

      @@pipolwes000 to be fair, there are only 9 regular polyhedra in 3d. Nothing Jan mentioned after the Kepler-poinsot solids was actually a polyhedron.

    • @lyrimetacurl0
      @lyrimetacurl0 3 года назад +12

      @@LeoStaley *finite polyhedron anyway
      There are only 5 regular convex polyhedra (as the other 43 are not convex).

    • @pipolwes000
      @pipolwes000 3 года назад +9

      @@LeoStaley If a shape in 3d space is face-, vertex-, and edge-transitive, then it's a regular polyhedron. Nothing about this definition precludes shapes with infinitely many vertices. The regular planar tilings meets these conditions (I think trivially), and so unless you use a more restrictive definition, the tilings are regular polyhedra.

  • @NthMetalValorium
    @NthMetalValorium 8 лет назад +412

    I wish I hadn't subscribed to this channel.
    so I could hyper-subscribe.

    • @standupmaths
      @standupmaths  8 лет назад +125

      It's ok, I'll upgrade your subscription for you.

    • @CharTheDude
      @CharTheDude 8 лет назад +8

      +standupmaths where can I hyper-hyper-subscribe

    • @PyroChiliarch
      @PyroChiliarch 8 лет назад +1

      +CharTheDude 6:17 Top Left Corner!!!!!!!!!!! CLICK IT BEFORE THE HYPER DIAMOND REVERTS TO 3D AND TEARS SPACE TIME KILLING US ALL!

    • @slimegoo27
      @slimegoo27 8 лет назад

      Bam, just hyper-subscribed.

    • @leif1075
      @leif1075 3 года назад

      @@standupmaths What about the video of they guy sayi ng t here re are ac tu ally 48 regular platonic solids? Do yiu need to update this?

  • @Darkassassin09
    @Darkassassin09 8 лет назад +436

    I hope your animator got a raise...

    • @johnsadena1043
      @johnsadena1043 7 лет назад +72

      He did. Into the fourth dimension.

    • @josgeerink9434
      @josgeerink9434 6 лет назад +5

      Stella4D look in description

    • @Ewumm
      @Ewumm 4 года назад +5

      I hope the computer got a graphics card upgrade, cause jesus christ that would take a lot of rendering power

    • @oosmanbeekawoo
      @oosmanbeekawoo Год назад

      You cannot donate to Wikipedia

    • @deawilld4346
      @deawilld4346 Год назад +2

      @@Ewumm not really. Those are just vertices connected with lines, and there are only hundreds of them. Modern games have a lot more elements in one scene, yet no complicated lighting, fancy shaders and all the 'difficult graphic' stuff. The animation can be run on any pc, even laptop. I've got more questions about building the shapes. (that involves CPU btw. And a fair amount of intellectual work to write the program))

  • @zander9698
    @zander9698 3 года назад +299

    I'm just here to hang out with all the jan Misali fans insisting there's 48 platonic solids
    even though there's a difference between platonic solids and regular polyhedra, and his video made that pretty clear, I thought

    • @LeoStaley
      @LeoStaley 3 года назад +17

      He didn't make it clear, but he also didn't make it clear that he was using extremely non-standard definitions of both polyhedra and polygon. The universal definition of polygon states that they *are* flat, two dimensional. And by virtually every standard definition, polyhedra are finite figures. And 3 dimensional, too btw, so claiming the 2 dimensional tailings of the plain are polyhedra is simply absurd.

    • @zander9698
      @zander9698 3 года назад +36

      sir, this is a wendy's

    • @TavartDukod
      @TavartDukod 3 года назад +50

      @@LeoStaley he literally starts the video with the definition of what he considers a regular polyhedra, and gives clear explanations of why certain shapes fall under the definition whenever objections are possible (such as when he introduces apeirohedra or petrials). He emphasizes again and again that his answer is correct only under his definitions. I have no idea how he could possibly make it more clear.

    • @LeoStaley
      @LeoStaley 3 года назад +5

      @@TavartDukod he doesn't give a useful definion, and he later goes on to include figures which contradict his definition. Doesn't anybody watch videos with the slightest critical eye anymore?

    • @LeoStaley
      @LeoStaley 3 года назад +2

      @@TavartDukod and my point was that he should have made it clear that his definition was well outside the accepted normal definition.

  • @sineadthomas2024
    @sineadthomas2024 3 года назад +224

    When a theoretical non-Euclidean shape gets acknowledged before you
    *sad Kepler Solid noises*

    • @qwertyTRiG
      @qwertyTRiG 3 года назад +56

      Have you seen jan Misali on the 48 regular solids?

    • @person_guy3505
      @person_guy3505 3 года назад +39

      @@qwertyTRiG 90% sure me watching that video is why this one popped up in my recommended.

    • @sineadthomas2024
      @sineadthomas2024 3 года назад +6

      TRiG (Ireland) Yeah..... I did...

    • @Adam-zt4cn
      @Adam-zt4cn 3 года назад +13

      Hello there, fellow those-that-had-this-video-recommended-in-the-sidebar-after-watching-the-one-with-48-regular-polyhedra.

    • @raskolnikov3799
      @raskolnikov3799 3 года назад +3

      @@Adam-zt4cn Howdy!

  • @dan339dan
    @dan339dan 8 лет назад +238

    1:51 Possessed Matt

    • @LillianWinterAnimations
      @LillianWinterAnimations 8 лет назад +2

      +TheCheungDan Woosh!

    • @saulmcshane7090
      @saulmcshane7090 8 лет назад +55

      Clearly Matt was breaking into the fourth dimension

    • @kanecobe
      @kanecobe 8 лет назад +19

      +TheCheungDan dont you fins it weird that he said "witch" as it happened? *plays x-files music*

    • @OrchidAlloy
      @OrchidAlloy 8 лет назад +2

      +Saul McShane His book taught him much, indeed!

    • @lietkynes81
      @lietkynes81 7 лет назад +11

      I'm afraid he can't say the word "square" anymore without risking "parker-squaring" what he's doing.
      (Meh. It's an almost funny joke.)

  • @patricberggren8390
    @patricberggren8390 8 лет назад +51

    You know, if my maths teacher would just be half as enthusiastic about mathematics as you are, my classes would be a whole lot more fun than they currently are.

  • @justinkoos9899
    @justinkoos9899 8 лет назад +31

    I don't know how I feel about calling the "hyper-diamond" the 4-D equivalent of the rhombic dodecahedron. Because the hyper-diamond is made up of triangles (actually octahedrons) , not rhombuses. But I do acknowledge they have similar properties.

    • @matstruija5670
      @matstruija5670 2 года назад +6

      You know. Both of those shapes are made out of bipyramids. 2-D bipyramid is rhombus and 3-D bipyramid is octahedron.

    • @aguyonasiteontheinternet578
      @aguyonasiteontheinternet578 Год назад

      @@matstruija5670 are bipyramids*

    • @matstruija5670
      @matstruija5670 Год назад

      @@aguyonasiteontheinternet578 2d pyramid is a triangle and bipyramid is two 2d or whatever dimension pyramids with connected bases.
      Most people maybe think that connecting 2d pyramids makes a quadrilateral which is not wrong.
      I would say that it is looking at it in a different angle.
      Angle

  • @soton4010
    @soton4010 3 года назад +42

    I want to see his response to jan misali video

    • @LeoStaley
      @LeoStaley 3 года назад +7

      How about this: platonic solids are convex. Literally nothing Jan misali mentioned after the platonic solids is convex. He was just talking about strictly regular figures. Not to mention he was using incredibly non-standard definitions of both polyhedron and polygon. Skew polygons are polygons in exactly the same sense that stone lions are lions; they aren't. Polygons, by the core, standard, universally agreed on definition, are flat. And infinitely extending figures are not polyhedra either, they are closed shapes with boundaries. Nothing he mentioned after the Kepler-poinsot solids is even a polyhedron.

    • @phyr1777
      @phyr1777 3 года назад +11

      ​@@LeoStaley there is nothing in the definition of a polygon stating that it has to be flat. there is also nothing in the definition of a polyhedra stating that it can't be infinite :)

    • @nadarith1044
      @nadarith1044 3 года назад +8

      ​@@LeoStaley Misali was talking about regular polyhedra, which don't require themselves to be convex
      also, i'm not sure if plato specifically said the solids need to be convex and this requirement wasn't tacked on later, its not as if he knew of non-convex regular polyhedra back then
      you seem to think that just because the shapes were ridiculous then they don't count, but that's not how it works here, the definition needs to be very strict else they're fair game, and the apeirohedra are very much polyhedra while tillings are like a degenerate polyhedra, and he could go much, MUCH further, as the definitions of either the platonic solids nor regular polyhedra don't specify that the space has to be euclidean or 3-dimensional, only that the solid iself is 3d, so shapes that can only exist in hyperbolic space or are skewed into 4d space are fair game, i don't think they specifically exclude degenerates either, and a regular hexagon based polyhedron is possible, its just that it'd be a degenerate with a height of 0

    • @EDoyl
      @EDoyl 3 года назад +1

      @@phyr1777
      There's no such thing as "The" definition of a polygon or polyhedron. Jan Misali used an elegant but nonstandard definition based solely on symmetry, but more commonly-used definitions do indeed require flat finite polygons.

    • @limeylime8027
      @limeylime8027 3 года назад +1

      @@EDoyl well that still would give any solid made from actual polygons, mainly the Kepler-poinsot polyhedra, the regular tilings, and the Petrie-coxeter polyhedra merit. So there isn’t just 5 anyways.

  • @unvergebeneid
    @unvergebeneid 8 лет назад +28

    "There are SIX Platonic Solids" Who else imagined Picard screaming that at a Romulan?

    • @xTheUnderscorex
      @xTheUnderscorex 3 года назад +5

      Nobody, he would scream it at a Cardassian

    • @unvergebeneid
      @unvergebeneid 3 года назад +3

      @@xTheUnderscorex indeed, my bad.

  • @isfiyiywafibc6qaiiiiiiiiii570
    @isfiyiywafibc6qaiiiiiiiiii570 8 лет назад +252

    You drew on a book :(

    • @isfiyiywafibc6qaiiiiiiiiii570
      @isfiyiywafibc6qaiiiiiiiiii570 8 лет назад +7

      +Ky Kanchuga With a pen?

    • @starwarsjk99
      @starwarsjk99 8 лет назад +37

      +ISFiYIywAFIBc6qAIIIIIIIIIIIIIIIIQrXTJiCtY3Asd4WF But he wrote it so its ok

    • @luccagiovani
      @luccagiovani 8 лет назад +32

      Yes, everything that I write is final.
      No reasons for pencils, that's childs play.

    • @alh84001hr
      @alh84001hr 7 лет назад +36

      And he found a remarkable proof that it is _the_best_ platonic solid, but there was not enough space in the margi

    • @MrPluron7
      @MrPluron7 7 лет назад +44

      he drew on his own book, that he wrote, really he just edited it post publication ;)

  • @Littlefa3
    @Littlefa3 8 лет назад +22

    4:07 it felt like it was attacking me

  • @pipolwes000
    @pipolwes000 3 года назад +6

    The Platonic solids are the five *strictly convex* regular polyhedra. There are more regular polyhedra than just the five platonic solids.
    (Assuming a regular polyhedron is defined as a shape in 3d euclidean space which is face-, edge-, and vertex-transitive).

  • @lawrencecalablaster568
    @lawrencecalablaster568 8 лет назад +7

    Matt, you, your channel, & your book are all amazing! :) I love Platonic solids & their 4D polychoron counterparts, as well as the many Archimedean solids.

    • @standupmaths
      @standupmaths  8 лет назад +5

      Ooh yes, I'm a big fan of the Archimedean solids as well. The cuboctahedron may be my favourite.

    • @lawrencecalablaster568
      @lawrencecalablaster568 8 лет назад +1

      :) Awesome! I think that my favourite Archimedean solid might be the great rhombicosidodecahedron. My favourite Platonic solid, however, is the wonderful dodecahedron. I'd have to say that my favourite Platonic polychoron is the commonly known, yet still beautiful, hypercube, though the 4-orthoplex (hyperoctahedron) comes close. Which is your favourite?

  • @tyhayter5022
    @tyhayter5022 4 года назад +10

    the d30 is pretty sweet. the number of sides is divisible by 1, 2, 3, 5, 6, 10, 15 and 30 so you can roll it and make most of the platonic die that way. you can roll multiple times multiplicatively to make a dice with n sides so long as n is solely divisible by the primes 2, 3 and 5. That includes the d4, d6, d8, d12 and d20 all in one dice

    • @ValkyRiver
      @ValkyRiver 2 года назад

      What about d120?
      120 is divisible by 4, 6, 8, 12, 20

    • @moondive4ever
      @moondive4ever Год назад +1

      Just because there are other shapes that can make dice. Doesnt mean that every single shape "qualifies".

    • @tyhayter5022
      @tyhayter5022 Год назад

      @@moondive4ever I was talking about simulating the probabilities of other dice using the d30. Roll a number mod x, where x is a factor of 30, and for dice that aren't factors of 30 (d8 for example) you can take the d30 mod 2 and roll 2^0, then 2^1, then 2^2 (where 000 can act as 8). The d30 is the smallest dice possible, both mathematically, and by shape, that contains prime factors of each platonic solid

    • @tyhayter5022
      @tyhayter5022 Год назад

      @@ValkyRiver d120 absolutely works, and same for d60

    • @timeisahorse114
      @timeisahorse114 10 месяцев назад +1

      It could also function as a D10 but that's not even an archimedean solid, let alone a platonic solid

  • @TunaAlert
    @TunaAlert 8 лет назад +115

    those look trippy... probably because you drew 4d objects on a 2d canvas...

    • @masonhawver3577
      @masonhawver3577 4 года назад +9

      Well how he is depicting those 4d shapes is by illustrating their shadow; 3d shapes have a 2d shadow and 4d shapes have a 3d shadow, so we can't really see 4d shapes; however, we can see their shadow, that's why they appear to be " trippy ".

    • @jaguarr314
      @jaguarr314 3 года назад +1

      It's actually still 3D, just rotating in the fourth dimension, like a 2D slice of a 3D cake.

    • @TunaAlert
      @TunaAlert 3 года назад

      Jaguar Playz these are not slices of 4d objects but rather 4d objects projected onto a 3D space which was then projected onto a 2d space.

  • @AJBooker
    @AJBooker 3 года назад +71

    can we get an update with the full 48 ? :•P

    • @Phantoms3709
      @Phantoms3709 3 года назад +13

      ive seen that video aswell, whcih means this video is LACKING!

    • @MonsieurSwag
      @MonsieurSwag 3 года назад +5

      yes Yes YES YES

    • @LeoStaley
      @LeoStaley 3 года назад +18

      No, because none of those additional "polyhedra" Jan misali mentioned were convex, which is a required for platonic figures.

    • @MonsieurSwag
      @MonsieurSwag 3 года назад

      @@LeoStaley what is convex

    • @LeoStaley
      @LeoStaley 3 года назад +2

      @@MonsieurSwag basically, none of the outer faces can "see" any of the other outer faces, or if you're on the inside, you can "see" any other face from any face.

  • @duckles426
    @duckles426 3 года назад +14

    Jan misali is just thinking, "if only..."

  • @TatooineWindAndFire
    @TatooineWindAndFire 8 лет назад +82

    D&D player, just going "d4, d6, d8, d12, d20"

    • @purrplaysLE
      @purrplaysLE 5 лет назад +1

      d10

    • @General12th
      @General12th 5 лет назад

      d14

    • @elnico5623
      @elnico5623 5 лет назад +3

      The sixth platonic solid is the d120

    • @Leonardo-G
      @Leonardo-G 3 года назад +4

      Imagine all the 4D dice tho. you got a 5d, 8d, 16d, 24d, 120d, and 600d.

    • @Darchengal
      @Darchengal 3 года назад +4

      @@Leonardo-G Just imagine rolling a 1 on a d600, or that one time you rolled a critical on your D600, immediately ascension to Godhood....

  • @MelindaGreen
    @MelindaGreen 6 лет назад +3

    The 4 Kepler-Poinsot polyhedra are every bit as regular as the Platonic solids. Also the 3 regular skew apeirohedra if we include repeating finite Euclidean spaces and not just the standard infinite one.

  • @maxnullifidian
    @maxnullifidian 5 лет назад +4

    I've noticed that the 5 Platonic solids have dualities that are very similar to the dualities of the 5 string theories. The heterotic SO(32) and the heterotic E8xE8 are dual, the type IIA and IIB are dual, with the type I being dual to itself. I don't know if this has any significance, but it's interesting.

  • @Antenox
    @Antenox 8 лет назад +69

    d4
    d6
    d8
    d12
    d20
    Dungeons & Dragons taught me geometry

    • @standupmaths
      @standupmaths  8 лет назад +36

      The icosahedron will always be linked to rolling for initiative.

    • @someguyonyoutube4285
      @someguyonyoutube4285 8 лет назад +4

      You find yourself in a 4 dimensional dungeon with 4D monsters. You could do a perception roll but no matter how high it is you will never be able to perceive the fourth dimension because you aren't a hyperspace alien

    • @shiningwhiffle
      @shiningwhiffle 8 лет назад +1

      +standupmaths Actually, that depends on which edition you're playing. The Frank Mentor "Basic" D&D from the 80's used a d6 IIRC and 1st and 2nd edition of AD&D used a d10, which is an interesting grey area since the true d10 is non-Platonic but originally a double-labeled icosahedron was used.

    • @VeteranVandal
      @VeteranVandal 8 лет назад

      +Antenox So now there is a need for 4dimensional dices. Just to make you learn this video. Right?
      Well, what will we roll with a hypericosahedron??? I mean it has to be something that goes from 1 to 1200... Luck of some sort, perhaps.
      It must be boring to be a 10d being thought. So little regular polytopes for dices...

    • @Antenox
      @Antenox 8 лет назад +1

      VeteranVandal
      That's for what we call "D&D Epic Level Adventures"

  • @VeloLEV
    @VeloLEV 3 года назад

    Thank you. Your enthusiasm for maths invigorates my own!

  • @TyYann
    @TyYann 8 лет назад +73

    I would have said the square is a regular quadrilateral, not a regular rectangle, to be consistent. But I'm a bad guy. ;~)

    • @someguyonyoutube4285
      @someguyonyoutube4285 8 лет назад +6

      That's what I would've said too. In maths everything has like 3 or 4 different names.

    • @standupmaths
      @standupmaths  8 лет назад +49

      You crazy quadrilateral people.

    • @rmsgrey
      @rmsgrey 8 лет назад +2

      +TyYann A square is a special case of: a polygon; a quadrilateral; a kite; a trapezium; a parallelogram; a rhombus; a rectangle. There are probably other things I've missed in that list...

    • @adb012
      @adb012 8 лет назад +8

      +Josh Lovasz
      If we really wanted to be consistent we should call them either:
      - triangle, tetraangle, pentaangle, hexaangle..., or
      - trigon, tetragon, pentagon, hexagon..., or
      - trilateral, quadrilateral, pentalateral, hexalateral...

    • @denisl2760
      @denisl2760 8 лет назад +2

      +adb012 nobody wants to be consistent

  • @OutbackBoy
    @OutbackBoy 3 года назад +10

    48 regular polyhedra smh

  • @CaJoel
    @CaJoel 6 лет назад +9

    1:52 I’m convinced you’re a glitch In the system

  • @MuzikBike
    @MuzikBike 7 лет назад +10

    Why do the vertices of the hypertetrahedron and hyperoctahedron like to slap me in the face so much?

  • @RokeyGames
    @RokeyGames 8 лет назад +18

    Awesome job on the animations! Very professional. Keep up the great work Matt.

    • @standupmaths
      @standupmaths  8 лет назад +12

      Thanks! I probably spend longer on the animations than I really should.

    • @deathsheir2035
      @deathsheir2035 8 лет назад +1

      +standupmaths you spend the right amount of time, to make each one look brilliant. You care about quality and it shows, and we love you for it.

  • @Refrez-
    @Refrez- 4 года назад +50

    Just found this randomly when looking into platonic solids. This isn’t a platonic solid, platonic solids are regular polytopes in 3 dimensions this shape only works in 4-D.

    • @456MrPeople
      @456MrPeople 3 года назад +13

      He probably should have said Platonic analogue

    • @arcycatten
      @arcycatten 3 года назад +3

      It’s a 4-D polytope

    • @angelmendez-rivera351
      @angelmendez-rivera351 3 года назад +5

      It is a platonic hypersolid.

    • @Inversion10080
      @Inversion10080 3 года назад +3

      The technical name for those is "Convex regular 4-polytope". Calling them "4D platonic Solids" is a lot nicer IMO.

    • @tafazzi-on-discord
      @tafazzi-on-discord 3 года назад

      @@Inversion10080 you don't get to make up language just because it sounds nicer. "Cold" sounds better than "Hypothermia" but they're not interchangable.

  • @officialurl
    @officialurl 7 лет назад +52

    The video title is very misleading. By definition, a Platonic Solid is... A solid. Anything bigger would be considered a polytope, not a polyhedron.

    • @danielsebald5639
      @danielsebald5639 3 года назад

      @@metachirality “polyga”
      :unknown:

    • @AlbertTheGamer-gk7sn
      @AlbertTheGamer-gk7sn 10 месяцев назад

      A 2-solid. A 1-solid is a 2D shape, a 2-solid is a 3D shape, a 3-solid is a 4D space, and so on. Well, the "solid" he describes is a 3-solid, and not a 2-solid.

  • @milkywaykid3440
    @milkywaykid3440 6 лет назад

    enjoyed this and I may purchase your book kind sir

  • @timeisahorse114
    @timeisahorse114 10 месяцев назад +2

    The hyper-diamond could also be seen as a 4D cuboctahedron

  • @AlexKing-tg9hl
    @AlexKing-tg9hl 5 лет назад +4

    0:38 it’s a regular quadrilateral. Technically

  • @electromika
    @electromika 8 лет назад +7

    03:30 thats actually really fucking cool
    gotta get myself a floating rhombic dodecahedron someday

  • @ihatethesensors
    @ihatethesensors 6 лет назад

    Thank you so much. That was beautiful!

  • @ZakeirSnake
    @ZakeirSnake 2 дня назад

    I understood very little of this, but it's incredibly fascinating. Thank you for sharing!

  • @rb919
    @rb919 6 лет назад +3

    I'm just happy that someone even made a vid about the 24-cell at all, and I'd never heard of it referred to as a hyper-diamond.. which I prefer now, as 24-cell sounds too much like.. a really cheap prison ; P It's like they named the shape in honor of the antithesis of it's true function. "Hyper-diamond" finally liberates it : )

  • @Matthew.Morcos
    @Matthew.Morcos 3 года назад +26

    Only 6 Platonic Solids? Maybe back in 2015. Everyone know there are 48

    • @LeoStaley
      @LeoStaley 3 года назад +3

      Jan misali was ridiculously incorrect with that video. Not to mention the fact that platonic solids are explicitly convex. He was using a completely nonstandard definion of polygon (yes, they do have to be flat, two dimensional), without informing his audience that he was doing so.

    • @quacking.duck.3243
      @quacking.duck.3243 3 года назад +18

      @@LeoStaley jan Misali never said those 48 were Platonic solids though.

    • @sushi-mayo
      @sushi-mayo 3 года назад +14

      @@LeoStaley jan Misali said *48* polyhedra, not platonic solids

    • @LeoStaley
      @LeoStaley 3 года назад +7

      @@sushi-mayo except that nothing he described after the Kepler-poinsot solids was even a polyhedron. A polyhedron, by definition, is 3 dimensional, so it is absurd to claim that a 2d tiling of the plane is a polyhedron. There are some contexts where some mathematicians use polyhedra to refer to other figures even above 3 dimensions, but none of them would include any 2 dimensional figure like a tiling of the plane. Later, he claims that a polygon doesn't need to be 2 dimensional when that is in fact a core part of the definition of polygon. Skew polygons are not actual polygons any more than polyhedra are polygons. They are a generalization of the idea of polygons in much the same way that polyhedra themselves are a generalization of polygons.

    • @LeoStaley
      @LeoStaley 3 года назад +3

      And notice, people, that this very comment we're replying to proves that people misunderstood the scope of Jan's video, which isn't surprising, because of the way he framed it.

  • @Sebi0043
    @Sebi0043 8 лет назад +1

    I just read the very same chapter today, what a coincidence!
    I love your book so far!

    • @standupmaths
      @standupmaths  8 лет назад

      I hope you enjoy the second half as much!

    • @Sebi0043
      @Sebi0043 8 лет назад

      I surely will. You have a great sense of humour, very punny!

  • @rb919
    @rb919 6 лет назад

    First of your vids I've seen, gonna continue on and check out your lecture @ R.I. and your book looks raaad : )

  • @Mrsparky492
    @Mrsparky492 3 года назад +19

    What is your opinion on the
    stellated dodecahedron?

    • @Choinkus
      @Choinkus 2 года назад

      The great icosahedron is the best regular polyhedron. Fight me

    • @egon3705
      @egon3705 2 года назад

      @@Choinkus i'm more of a great dodecahedron guy myself

  • @DrRawley
    @DrRawley 8 лет назад +57

    There are four lights!

    • @DrRawley
      @DrRawley 8 лет назад +3

      BraneBrain
      Hella. It's pretty intense and a great character exploration of Picard.

    • @Hen16
      @Hen16 8 лет назад

      +DrRawley it's a rip off from George Orwell, but I'm not dissing it.

    • @denisl2760
      @denisl2760 8 лет назад +3

      +DrRawley Great reference, but how does it apply to the video?

    • @DrRawley
      @DrRawley 8 лет назад

      Denis Lipatnikov
      I had just watched that episode of star trek the previous day, so it was the first thing that came to mind. a bit of mirth if you will.

    • @skyr8449
      @skyr8449 8 лет назад +2

      +DrRawley you sir are the greatest man to have ever lived.

  • @xaytana
    @xaytana 7 лет назад

    The orthographic projections look amazing. Makes me think of the whole sacred geometry stuff.
    I'd love to find versions of them without all the solid circles, maybe make a carpet with the design or something.

  • @AfroGamer
    @AfroGamer 8 лет назад +2

    Great video. Do you have videos that go into more advanced and detailed stuff. I'm 16 and I love the fourth dimension. I got interested in it at the age of 13 when I noticed geometric patterns with shapes and stuff and I only found you recently. I love your videos.

  • @lindseys.8693
    @lindseys.8693 8 лет назад +36

    I like to think about 3D->4D by comparing it to 2D->3D and 2D->1D, doesn't take a lot of prior knowledge to come to conclusions about it. For example, hyperspace beings could see inside us, just like we could see inside 2D beings on a plain, if we see them from above.
    Try it! :) Just remember 4D's not supposed to make any sense for our 3D brains...

    • @bryanwan6169
      @bryanwan6169 8 лет назад +15

      Flatland.

    • @lindseys.8693
      @lindseys.8693 8 лет назад +1

      Cryp Tic yes.

    • @prototypeinheritance515
      @prototypeinheritance515 8 лет назад

      try analytic geometry. These 4d images are generated by these methods, and it isn't even that hard

    • @coopergates9680
      @coopergates9680 8 лет назад

      Rotations in 4D? I will use stereographic coordinates.

    • @Reragi
      @Reragi 6 лет назад

      See inside us... pretty kinky

  • @CasiMediocre
    @CasiMediocre 9 месяцев назад +3

    "There are only 5 regular polyhedra"
    jan misali: Am I a joke to you?

    • @asd-wd5bj
      @asd-wd5bj 5 месяцев назад +1

      All platonic solids are regular polyhedra but not all polyhedra are platonic solids

  • @TaylorTheOtter
    @TaylorTheOtter 6 лет назад

    That hyper-icosahedron looks amazing!

  • @Jellylamps
    @Jellylamps 5 лет назад

    It is the best indeed. I have a puzzle similar to a rubiks cube called the curvy copter. It’s a cube shaped puzzle based on the rhombic dodecahedron and the various ways it turns make for the most fun puzzle i have ever solved

  • @savajevtic8040
    @savajevtic8040 8 лет назад +12

    How does the hyperdiamond get to be a Platonic solid if it's not made out of regular polyhedrons?

    • @DanDart
      @DanDart 8 лет назад +12

      it does and it is! regular octahedrons.

    • @santiagobecerra5000
      @santiagobecerra5000 6 лет назад

      Face polygons aren't regular

    • @ninjafruitchilled
      @ninjafruitchilled 6 лет назад

      But I guess the faces where the octahedra join are not themselves polygons, yes? So it is still a bit different to the other 4D "platonic solids" yes?

  • @FrederikMeynen
    @FrederikMeynen 8 лет назад +4

    I love this channel! Just bought the book (in store, didn't know you sold them as well).
    BTW, I love the song you use, can I get it somewhere?

    • @icrin_
      @icrin_ 8 лет назад +1

      +FrederikMeynen I want that song as well.

    • @standupmaths
      @standupmaths  8 лет назад

      Yes, I wanted to sell them myself so I could sign them for people. The song is my theme song and currently not available anywhere!

    • @gojoubabee
      @gojoubabee 8 лет назад +1

      +standupmaths PLEASE make it available for purchase!! I love the standupmaths theme song!!!

  • @BlueElevenBlocks
    @BlueElevenBlocks 2 года назад

    I love this guy's intro and the 4th dimension

  • @mydotasopro
    @mydotasopro 8 лет назад

    your channel never bores me.
    I laughed every single time!!

    • @standupmaths
      @standupmaths  8 лет назад

      Great to hear! Hopefully I'll keep you laughing at such a predictable rate.

  • @RexGalilae
    @RexGalilae 8 лет назад +11

    1:39
    We can call that "Platonic Love" then? =P

    • @ilangated
      @ilangated 8 лет назад +1

      +Mohammed Zaid booooooooo

    • @RexGalilae
      @RexGalilae 8 лет назад

      Kremlit the Forg
      :(

    • @ilangated
      @ilangated 8 лет назад

      +Mohammed Zaid

  • @prasanttwo281
    @prasanttwo281 4 года назад +6

    But there's only ONE true parabola

  • @quinn7894
    @quinn7894 Год назад +1

    Cool fact: Half the 4D Platonic solids can tile 4D space. (the hypercube, the "hyper-octahedron", and the hyperdiamond)

  • @nightmare9566
    @nightmare9566 8 лет назад

    I love the amount of videos lately :)

    • @standupmaths
      @standupmaths  8 лет назад

      Thanks! I'm trying to put out regular videos. It just takes a lot of time.

    • @nightmare9566
      @nightmare9566 8 лет назад

      standupmaths Oh, and could you make something about right triangles with equal area and perimeter? Might be below the level of the videos, or just not interesting enough, though...

  • @sydneytalapov6441
    @sydneytalapov6441 8 лет назад +6

    YOU DREW IN YOUR BOOK! Well I guess someone will want it.

  • @jamez6398
    @jamez6398 8 лет назад +5

    I love the hyper diamond. I want one. But I don't live in the fourth dimension. Yet.

    • @epsleon
      @epsleon 8 лет назад +3

      Maybe you do live in the 4th dimension.
      If you were 2D how would you know you don't live on a cube?

    • @jamez6398
      @jamez6398 8 лет назад +3

      epsleon We live in eleven dimensions.

    • @ZazLWheel
      @ZazLWheel 8 лет назад

      @James: indeed.

    • @jamez6398
      @jamez6398 8 лет назад +1

      ***** I was waiting until someone got that physics joke.

    • @zacharyfilion1437
      @zacharyfilion1437 7 лет назад +1

      in 4d galaxies would not be able to form and would remain as dust clouds

  • @CGMaat
    @CGMaat 2 года назад

    Beautiful ; of this world but not of the world; how lovely!
    I dont know why these are so beautiful especially how they dance !

  • @dezziss
    @dezziss 5 лет назад

    You make me audiofobic with this noise you use in the back/foreground.

  • @Leidon00
    @Leidon00 8 лет назад +12

    viewer cant believe nor understand the hyper-diamond. He screams Geometrically

    • @maxnullifidian
      @maxnullifidian 5 лет назад

      Hyperdiamonds are a girl's best friend...

    • @gordonweir881
      @gordonweir881 3 года назад

      @@maxnullifidian You mean SuperGirl's best friends....

  • @almoglevin
    @almoglevin 8 лет назад +6

    But... but... you wrote in a book!..

  • @logofmusic
    @logofmusic 8 лет назад

    oh my days, this is awesome!

  • @JoshwaLaw
    @JoshwaLaw 2 года назад

    I saw a hyper diamond (or rather the best representation of one we can make) the other day, and I was awestruck by it 🥰

  • @DanDart
    @DanDart 8 лет назад +63

    > "watch my Royal Institution 4D lecture"
    the lecture wasn't 4D :p

    • @DavidWangazsr
      @DavidWangazsr 8 лет назад +8

      Well, the 4th dimension (and the 3rd dimension) were folded up so small that you couldn't see them.

    • @williamrutherford553
      @williamrutherford553 8 лет назад +1

      +Joe Holland Time isn't the fourth dimension. Relativty says that time dimensions are seperate from spacial dimensions, so the 4th dimension != time.

    • @appleturdpie
      @appleturdpie 8 лет назад +1

      +William Rutherford Time is the fourth dimension but not the fourth spacial dimension.

    • @williamrutherford553
      @williamrutherford553 8 лет назад +1

      +appleturdpie it was a math video. He was talking about 4D shapes. That means he was talking about space, not time.

    • @LillianWinterAnimations
      @LillianWinterAnimations 8 лет назад +3

      +appleturdpie Well.. It's one of MANY dimensions. Sure, you can CALL it the fourth dimension. I could also call the Y axis the "fourth" dimension. Or perhaps time can be the first dimension. What I'm getting at here is that the labels "first", "second", etc, are entirely arbitrary.

  • @damnerd
    @damnerd 8 лет назад +7

    you forgot the best part about the rombic-dodecahedron: it tesselates the space! not sure about the hyper-variant, though.

    • @donwagner8126
      @donwagner8126 6 лет назад

      A rombic-dodecahedron is not made of regular polygons in 3D

    • @computercat8694
      @computercat8694 4 года назад

      The rhombic dodecahedron and all higher omniaugmented hypercubes tile space, since you can decompose every other cube of the ordinary cubic honeycomb into pyramids and glue them onto the remaining cubes.

  • @1NEFFIBLE
    @1NEFFIBLE 11 месяцев назад

    Great presentation 👌👍🥰
    I would make these as models built of drinking straws and fishing line, suspend them, and shine a flashlight through them as they spun just to see the shadows play😉

  • @LadyTink
    @LadyTink 7 лет назад +2

    2:39
    ER MER GERD
    I'm such a fanboy of that shape.
    Seriously, I've done many an evening reading up on it and whatnot.

  • @CyberCreeper22
    @CyberCreeper22 3 года назад +3

    me, who just watched a video about 48 platonic solids:
    pff pahetic

    • @LeoStaley
      @LeoStaley 3 года назад +1

      Is so painful that I have to keep correcting this stuff. Nothing Jan misali mentioned after the first 5 platonic solids is a platonic solid because none of them are convex. Plus, he was using wildly non-standard definitions of polyhedron *and* polygon.

    • @aguyonasiteontheinternet578
      @aguyonasiteontheinternet578 Год назад

      there was only ONE section in that video about platonic solids.

  • @ClarkManorDesign
    @ClarkManorDesign 7 лет назад +3

    You should collaborate with Trey Stone.

  • @teabagfc
    @teabagfc 8 лет назад +1

    The correct representation of the symbol for infinity. Very subtle ;-)

  • @michaeljeremyrichards6901
    @michaeljeremyrichards6901 5 лет назад +1

    REGULAR TETRAHEDRON: 4 triangular faces,6 edges,4 vertices
    REGULAR HEXAHEDRON: 6 square faces,12 edges,8 vertices
    REGULAR OCTAHEDRON: 8 triangular faces,12 edges,6 vertices
    REGULAR DODECAHEDRON: 12 pentagonal faces,30 edges,20 vertices
    and... THE REGULAR ICOSAHEDRON: 20 triangular faces,30 edges,12 vertices
    The Rhombic Dodecahedron is one of 13 Catalan Solids. Each face is a rhombus.

  • @deathpony698
    @deathpony698 8 лет назад +3

    the fifth beatle is clearly yoko ono

  • @Maou3
    @Maou3 3 года назад +7

    Wow... nice clickbait. I thought this definition assumed 3D euclidean space. However, there are 48 3D euclidean regular polyhedra, not 5.

    • @LeoStaley
      @LeoStaley 3 года назад +4

      Jan misali was wrong. He was using non-standard definitions for both polyhedra and polygons. Polyhedra are 3 dimensional, so 2d tilings of the plane don't count as polyhedra by anyone's definition. And the definition of polygon *does* define them as flat, 2 dimensional figures. Skew polygons are polygons in the same sense that stone lions are lions; that is, they aren't. And polyhedra are composed of polygon faces. Literally nothing he mentioned after the Kepler-poinsot solids was actually a polyhedron.

  • @jasonmcgee7457
    @jasonmcgee7457 8 лет назад +1

    Where can I find your outro song? I absolutely love it and would love the hear the whole song.

  • @davidfell466
    @davidfell466 8 лет назад

    The rhombic dodecahedron is the dual of the cuboctahedron which is not a Platonic Solids but the building block of the twelfth ffellonic form.
    Sometimes to much attention is placed on the vertices, faces and edges of polyhdera rather than the axes they describe.

  • @icrin_
    @icrin_ 8 лет назад +3

    What song is that at the end?

    • @shimble11
      @shimble11 8 лет назад +23

      +Icaro Vasconcelos Darude - Polygonstorm

    • @standupmaths
      @standupmaths  8 лет назад +9

      That is the Stand-up Maths theme song!

    •  8 лет назад +1

      +standupmaths, it reminds me of the Super Hexagon a bit.

    • @usArrr3
      @usArrr3 8 лет назад

      +standupmaths Is there a place to download / buy this song? :)

  • @JackDrewitt
    @JackDrewitt 8 лет назад +22

    STOP SPOILING UR BOOK! I'm planning to get it this Christmas dammit!

    • @daanwilmer
      @daanwilmer 8 лет назад +4

      +Jack Drewitt Don't worry, there's lots of stuff in the book that isn't on his channel yet :)

    • @standupmaths
      @standupmaths  8 лет назад +21

      Spoiler: I talk about prime numbers as well!

    • @stalfithrildi
      @stalfithrildi 8 лет назад +5

      +Jack Drewitt Or did you mean by writing on it, cos it killed me to see him scribble on the lovely page.
      I don't care if it was for a promotion, and he wrote the book. Christ, I don't even care if he soaked and crushed the papyrus himself then set the type by hand, it's just wrong to write in anything with an ISBN number.

    • @JackDrewitt
      @JackDrewitt 8 лет назад

      stalfithrildi no i didnt mean that, altho i can sort of see where ur coming from

    • @MarioFanaticXV
      @MarioFanaticXV 8 лет назад +2

      +stalfithrildi
      But you're okay with people doing it in books that predate ISBNs? Also, isn't "ISBN number" redundant? =P

  • @M6Cuerdas
    @M6Cuerdas 8 лет назад

    That last bit got me haha
    I wish I could see a glance of the actual fourth dimention :c

  • @Adamdun11
    @Adamdun11 8 лет назад +1

    0:53. Very smooth, mate. Bet you're proud of that.

    • @standupmaths
      @standupmaths  8 лет назад +1

      More than I am prepared to admit!

    • @Adamdun11
      @Adamdun11 8 лет назад

      +standupmaths Lovin' the videos; you're on a roll! Keep them coming (please).

    • @standupmaths
      @standupmaths  8 лет назад +1

      +Adam Duncanson I'm trying! The only problem is finding enough time.

  • @teguh.hofstee
    @teguh.hofstee 8 лет назад +3

    Nah, sixth one is the teapotohedron. :)

  • @subh1
    @subh1 8 лет назад +3

    "in the fourth dimension"????? NO NO NO!!! It is "in four-dimensional Euclidean space". You cannot pin down a "fourth dimension" just as you cannot pin down a "third dimension" in the 3-dimensional Euclidean space.

    • @cOmAtOrAn
      @cOmAtOrAn 8 лет назад +2

      +subh1 Sure you can. z is the third dimension. w is the fourth. Completely arbitrary, of course, but still can be useful.

    • @novameowww
      @novameowww 4 года назад

      Yeah, that's what I said, sodium chloride

    • @AlbertTheGamer-gk7sn
      @AlbertTheGamer-gk7sn 10 месяцев назад

      As 2D objects require 3D spaces to represent, and 3D objects require 4D spaces to represent. Since we have a "third dimension", we can use the fact to prove we are living in 4D Euclidean space. If we were living in 5D Euclidean space, we would have a "fourth dimension", and the Flatlanders are living in 3D Euclidean space.

  • @probablynot8154
    @probablynot8154 7 лет назад

    I have that book! Woo.

  • @hkayakh
    @hkayakh 10 месяцев назад +1

    “4th musketeer”
    “5th beetle”
    “6th tally hall member”

  • @acerockman3520
    @acerockman3520 7 лет назад +3

    At 1:52 there is a glitch

  • @hantrazaveri1566
    @hantrazaveri1566 3 года назад +8

    BRUH THERE ARE 48 REGULAR POLYHEDRON LOL GET GOOD GIVE ME UPDOOTS

    • @LeoStaley
      @LeoStaley 3 года назад +1

      Not convex. Jan misali never pointed that out, nor did he mention that he was using a totally nonstandard definition of polygon. The standard definition *does* require that they be flat, in 2 dimensions.

    • @dianachim9340
      @dianachim9340 3 года назад

      You mean 49 cus 5 plus the 43 from Jan miseali and 1 from here

  • @jellymunoz8555
    @jellymunoz8555 2 года назад

    4:06 also pentachoron, regular tetrahedral pyramid, regular 5-cell,4-simplex
    4:15 also tesseract, regular cubic prism, regular 8-cell,regular octachoron,4-hypercube
    4:21 also hexadecachoron, 4-orthoplex, regular 16-cell...
    4:24 also hecatonicosachoron,regular 120-cell
    4:39 also 600-cell, hexacosichoron

  • @TomtheMagician21
    @TomtheMagician21 2 года назад

    I know this is a really old video, but there is a new game demo out of a 4D version of Minecraft called 4D miner and its amazing! It's still in development but you should check it out by a guy called Mashpoe 👍

  • @omfgmouse
    @omfgmouse 8 лет назад +117

    As much as I love Matt Parker (I've even bought his book) I really don't like some of his nomenclature. Not because it doesn't sound cool, but because it's actually very misleading about why the various geometric figures exist in the ways they do.
    So I'm afraid I'm going to have to make a long and critical comment about it.
    Let's start with the video title. There are FIVE platonic solids. Platonic solids are 3D, because /solids/ are 3D. From Wikipedia, for example: "solid geometry is the traditional name for the geometry of *three-dimensional* Euclidean space".
    Platonic solids are also known as regular convex polyhedra. The equivalent in 4D is "regular convex polychora". Or in general, you have n-dimensional "regular convex polytopes". "4D Platonic solids" doesn't make sense because that's like saying "4D 3D regular convex polytopes".
    If you want to say there are six regular convex polychora, go ahead and say that. Don't say that there are six regular convex polyhedra ( = Platonic solids), because there aren't.
    Now, moving on. Hyper-diamond? Sure, you can cut up bits of a tesseract and reattach them to make an icositetrachoron (or 24-cell), and sure, that makes an interesting link with the rhombic dodecahedron, but the 24-cell doesn't have a single rhombus on it. Its faces are triangles and its cells are octahedra. There is no resemblence to rhombi.
    Let's have a gander around 5:10. "Icositetrahedron?" No, it's not often called that. There are various icositetrahedra, but those are different figures, and they live in 3D anyway, as the name would imply. The name you wanted is the /icositetrachoron/. As for Octacube? *googles*... The only reference I can see for that one is as the name of a sculpture representing the figure. And, sure, "hyperdiamond" appears on Wolfram Mathworld, but it's completely unreferenced.
    Also, 3:55... What's a "polytshorron"? It's from Greek, so it's pronounced with a hard ch / k sound. Polychoron. Look it up on Wiktionary if you like.
    Just to be clear, I've got no issues with names like the "hyperoctahedron", they're a bit of a mouthful but are accurate, since "hyper-" just means "higher dimensional analog of". Heck, "hyperdodecahedron" is probably easier to understand than "hecatonicosachoron", and definitely easier to remember, but my dislike of that series of names is neither here nor there. (I'd previously concocted my own nomenclature to deal with this too, but really I'm in no position to start talking about that, if you really want to know about it, you'll know where to find it.)
    Okay, I'm done. I'm probably going to get a million down-votes, but I'm not just going on a rant for the sake of it. I really like Matt Parker's work, I just wish he would do a little more research on the words he's using before teaching them to everyone else.

    • @Deadrooster000
      @Deadrooster000 8 лет назад +10

      +Keiji Ikari lol no one knows how to respond to that.

    • @JafarChou
      @JafarChou 8 лет назад +5

      What are you, Asian?

    • @omfgmouse
      @omfgmouse 8 лет назад +3

      +AbuJafar Choudhury I'm British for the record.

    • @LinkEX
      @LinkEX 8 лет назад +15

      »lol no one knows how to respond to that.«
      +Ayyy Lmao Well, maybe because there's simply not much to add to it.
      It's on point, informative, and manages to be very critical analyzing the video's faults while staying humble.
      I personally agree wholeheartedly with +Keiji Ikari's concerns about Matt's somewhat negligent use of terminology, and would consider it the best comment in this whole comment section even.

    • @Deadrooster000
      @Deadrooster000 8 лет назад

      same

  • @SeanMauer
    @SeanMauer 7 лет назад +5

    There's actually 7 platonic solids, the sphere is a one sided platonic solid.

    • @MuzikBike
      @MuzikBike 7 лет назад +13

      apparently not for some reason, it's a bit like saying 1 is a prime number.

    • @quillenkai6714
      @quillenkai6714 7 лет назад +6

      I believe it's because there are no faces, vertices or edges to be identical to one another, thus making it not a polyhedron, which I believe is one of the qualifications for being a platonic solid.

    • @ffggddss
      @ffggddss 7 лет назад +11

      *Polyhedron*
      - Only planar faces need apply.

    • @TicalaKing
      @TicalaKing 6 лет назад +1

      That's like saying a circle is a polygon, it isn't, poly means many and 1 isn't many

    • @keithstathem872
      @keithstathem872 6 лет назад +1

      If you think about it, a sphere is the limit of a regular infinihedron. At least, that's the only way I've been able to get it to make sense.

  • @dylansaus
    @dylansaus Год назад

    those 4d platonic solids look qutie trippy

  • @toast_stealer
    @toast_stealer 7 месяцев назад +1

    One of the rules of Platonic solids is that they must be in a 3 dimensional, Euclidean space.

  • @johnchessant3012
    @johnchessant3012 6 лет назад +1

    5:30 - Matt, we can see the string!! :D

  • @user-oi8re8fo5n
    @user-oi8re8fo5n 11 месяцев назад +1

    Can you do a video about Archimedean,Catalan and Johnson solids?

  • @primartyrthrax5109
    @primartyrthrax5109 5 лет назад

    An unobstructed Garnet Crystal will grow into a Rhombic Dodecahedron. They look amazing. After watching this I love mine even more now.

  • @SantiagoItzcoatl
    @SantiagoItzcoatl 6 лет назад

    love them !

  • @user-hp7ji2ru8y
    @user-hp7ji2ru8y 7 месяцев назад

    “In fact, I’ll highlight it right now”
    *draws a rectangle

  • @TevaJolicoeur
    @TevaJolicoeur 2 года назад

    My son found a cute magnetic shape toy. I noticed it had all the same sides (Diamonds). We were trying to figure out which Platonic Solid he was holding. Your video revealed we were looking at the Rhombic Dodecahedron.

  • @tsmeowth001
    @tsmeowth001 8 лет назад

    Is there an electronic version of your book? :3 as awesome as it would be to hold a solid copy, i wont be able to have a bookshelf for quiet a while

  • @justanormalfreak6855
    @justanormalfreak6855 6 лет назад

    I don't understand those 4D shapes.. maybe I need to get your book to get it o.o