See Part 1: kzread.info/dash/bejne/ZZWfpK-Mepadhc4.html Buy the dice at: www.mathartfun.com/DiceLabDice.html

@Twitchi

5 ай бұрын

Man, that was a great looking book, If only I knew where to get it from...

@mayukhpurkayastha2649

5 ай бұрын

W?-!at is this math India 🇮🇳🇮🇳

@arikwolf3777

5 ай бұрын

So when are you going to make tetrahedral d2's in the style of "The Royal Game of Ur"?

@Ansarkhan01780

5 ай бұрын

Support

@Ansarkhan01780

5 ай бұрын

500 hundred subscriber

“As a pure mathematician it is my inalienable right to do pointless things because they’re fun and cause you can.” I’d like to be a mathematician and this truly fills me with the utmost hope and determination. I want to do pointless things because they’re fun and I can.

@tiagom1665

5 ай бұрын

+1

@jyrinx

5 ай бұрын

Some mathematicians even get a bit sad if it turns out something is useful

@whatthefunction9140

5 ай бұрын

I want a t shirt with this quote

@mrphlip

5 ай бұрын

​@@jyrinxThere was a video on another maths channel... I forget what the topic was, I think it might have been an Another Roof video? Anyway, as an aside in the video they say "unfortunately, this does have applications", and that's a mindset that has stuck with me for a while...

@Math_Rap_and_GOP_Politics

5 ай бұрын

Paul Erdös felt this way too.

"That's pointless!" "Thankyou" 😂 gotta love a mathematician

I am always impressed on how Brady asks the best questions at the right time. I was just thinking about the fairness/independence of the results.

@AaronOfMpls

5 ай бұрын

Indeed! And yah, years of experience, I imagine; he's been making Numberphile for more than long enough to _think_ like a mathematician sometimes. And he trained as a journalist well before that.

@rustyrapp5673

5 ай бұрын

It’s almost as if these videos are produced in advance of filming…. Oh wait

I'd love to see the 2-3-4 dice poured in a clear resin with the inner symmetry (or just the cube) visible, like in Brady's visualization.

The d4 are actually amazing! Not only are they nerdy and beautiful, they also roll much better than tetrahedral d4! Like, the bane of everyone having to roll d4s is that the just won't effing roll!

Their prices are crazy and I mean that in a good way. All of that design effort, outlay for tooling etc and they are not that expensive for what they are. Kudos.

@LightPink

5 ай бұрын

They are all solid colored tho

I love those constant-width d4s! I can't wait to buy a set

when those dice of constant width are available, you'll sell a bajillion.

I am 100% adding these to my Christmas and birthday lists

That first one would be great for my minigun damage rolls! Xd4 is too much, and a “crit” 4 being more likely to roll a 1 just seems like good balance to me.

@brikilian7834

5 ай бұрын

It isn't more likely to roll anything. It's that certain combinations are more or less likely. There is a 1 in 4 chance of each number on a d4. But if the f4 turns up as a 4, the d2 was more likely to be a 1 than a 2. So, it only works the way you wish if your game requires that a crucial is rolled on a smaller die.

I remember learning about C2 continuity from The Continuity of Splines video would be cool to see a numberphile approach to the explanation of the different levels of continuity

@agargamer6759

5 ай бұрын

Haha, I was wondering why that term was familiar! Been a while since I watched that video

Those constant width dice are beautiful.

I'm a tabletop RPG player and a math nerd. I did buy several of those and use them regularly while playing. The skewed d6 is my favorite.

"As a mathematician it is my inalienable right to do pointless things because it's fun" spoke straight to my soul

Love that you pick Matt's book

Nice c: Wouldn't it also be cool if the numbers on those constant width d4 were on the faces? They're see-through, so you could read them.

The place people buy strange and unique dice are at gaming conventions. Places like PAX. Everyone wants those own unique dice. Sometimes unique sets for each character they make. The dice there go for up to 100's of dollars per set. Some made from metal, wood or have custom designs embedded within them. These these unique shapes could do well. Not sure about the 'recast' dice though, just because there are modification to each die, like rerolling 1s that would be awkward.

@rngwrldngnr

5 ай бұрын

Similarly while I really like the schlerman dice, I think needing to keep them separate for reliable results is probably a deal breaker (though distinctive coloring and size would help).

@unvergebeneid

5 ай бұрын

Another place where people buy these dice is the internet 😄

@wobblysauce

5 ай бұрын

And only useful as 2d6, of course, you could roll multiple pairs.

that first one is so clever the constant-width dice look so fun

Those clear dice need to come in 6 inch 'diameter' or larger. Super cool art pieces.

@alveolate

5 ай бұрын

they're so insanely smooooth that they look pretty just all on their own! the fun bonus that they spin really well is also kinda cool. and oh, they do function as dice xD

There was a Kickstarter a while back for a D Ultimate die. It's like your 2-3-4 die, but it has 120 faces and works as a 4, 6, 8, 10, 12, and 20 sided die. They're supposed to finally be shipping them out in a few months.

Pleasantly surprised at the Grand Illusions mention, surprised no talk of Louis Zocchi or any of his famous exhortations on dice-making. In particular, his spiel is pretty zealous about NOT putting dice through a tumbler and preferring to live with the blemish left by clipping and sanding down from a casting sprue instead. It's compelling enough to watch in full and at least makes a decent case for it, and he goes into fascinating specifics about the manufacturing process.

@andrewmartin3671

5 ай бұрын

Yes! Grand Illusions collab when? ;)

A huge family of TTRPGs - "Powered by the Apocalypse" games - use 2d6 as the core resolution system. Rolling up to a PbtA game with those recast 2d6 would be a seriously sexy move.

>"there aren't enough... dimentions or something" lol

For the constant-width d4, you could just take a regular tetrahedron and consider the spheres formed by having each vertex as the center and the others being points on each sphere, which, combined, would divide 3d space into 16 (unequal) sections. The section containing the tetrahedron would then be of constant width, and the edges and corners would be identical to each other (so they'd be equally affected by the tumbling process), analogous to the construction of the Reuleaux triangle; the proof is left as an exercise to the reader

You should do a video just on this 'C' concept of smoothness. Henry did a good quick job but I'm interested in learning more. EDIT: also I want to buy the constant width dice.

@daemanuhr

5 ай бұрын

I don't see the C2-smooth d4 on the website yet. He did say it was a sneak peak, but I wonder how long until they're available. In the meantime, I noticed they have rhombic dodecahedra d12, which is one of my favorite shapes (it tiles 3d space, similar to how a hexagon tiles 2d space). I think those, as well as the recast 2d6 and Sicherman 2d6, will make a nice gift set for a math nerd.

That alternative d3 has an obvious advantage that would have jumped out to a more mercenary soul: there are three big blank rectangles for ad space. (Thinking about it, the inability to easily produce branded dice has probably vexed game manufacturers for ages.)

@urgay1992

5 ай бұрын

Mercantile

Have you explored the idea of 4-dimensional dice? The values (D5, D8, D16, D24, D120, D600) for regular dice are easy to find, but a deeper look into the specifics and geometry and maybe simulation could be interesting

These are neat, however for the first set of dice in this video I can't help but say: d12 already exist and work as a stand in for a d4, d3 and d2.

Surpirsed you made this unlisted

@twixerclawford

5 ай бұрын

All the part 2s start out unlisted

@rngwrldngnr

5 ай бұрын

I'd have expected it to be over on numberphile2

Those first dice were way to much for my morning fog brain

The provided animations are definitely brilliant!!

The easter egg in this video is a glimpse in which we can see how acquainted Henry is with poltergeists.

The constant width d4 might genuinely be a better design than the sharp (dangerous!) normal design

@mitigatedrisk4264

5 ай бұрын

And they look delicious

@AaronOfMpls

5 ай бұрын

@@mitigatedrisk4264 Indeed, I could see someone making these in rock-candy or jellybean form. 😋

I could see a game designed around the recast 2d6. Something where the total determines your movement and then the d3 determines some other outcome (like fight/flight/freeze)

@joshuagardner4095

5 ай бұрын

Or you control 3 game pieces/characters and the d3 determines which actually moves.

Looking forward to the d4 of Constant Width! Be interesting to explore dice with more "faces" that retain constant width (and are C2 smooth), I haven't seen any 3D shapes outside the Reuleaux/Meissner tetrahedron, and it seems like it'd be weird if that was the only useful one given how 2D permits so many.

@Tumbolisu

5 ай бұрын

You can take any 2D shape of constant width and just spin it around to generate a 3D one, meaning there are infinitely many 3D shapes of constant width. However, these are not very interesting.

I like the engineering connections in this one!

The recast 2d6 has the same probability of sums, but “doubles” are drastically reduced as it’s only possible to get double 1, 2, or 3.

@r3hawk

3 ай бұрын

I was thinking the same thing. Would be interesting to play Monopoly or Parcheesi with them.

By sheer luck, you choose THAT book !

Great video, love the dice vids

He engineered the new dice to the requerments! The is just beautiful.

shame this video is unlisted, this one features Matt Parker (indirectly) and dices in this video are so much fun!

@numberphile

5 ай бұрын

It will be listed soon - I always make "part 2" videos unlisted at first so that people are more likely to see Part 1 first!

@Anonymous-df8it

Ай бұрын

@@numberphile That's clever! :)

Huge miss with the transparent d4 - should have put a mirrored number on the bottom

Those d4 are some of the most beautiful objects ever to watch

To me the more intuitive way to determine what numbers need to be on the dodecahedron for the Recast 2d6 is to use the chart at 5:11 -Divide it into quadrants -The bottom right and upper left quadrants are the same -Imagine picking up the bottom half and overlapping it with the top half, so the matching quadrants are overlapping/next to each other -Note that every column is a set of three numbers {n, n+1, n+2} in that order, so the {1, 2, 3} dice fits perfectly with these rows -End result: 1, 2, 3, 4 (×2), 5 (×2), 6 (×2), 7, 8, 9

I like the d2/3/4 dice. Beats what I usually do and that's rolling a d6 and saying 1 or 4 is 1, 2 or 5 is 2, 3 or 6 is 3 for d3 or odd is 1, even is 2 for d2.

9:24 yay stand up maths reference! That book is great, maths as a baseline but honestly just a lot of interesting history

"That's pointless!" "Oh, of course!"

There are enough ttrpgs that use just 2d6 to justify the 2d6 recast being a purchase you make

@bobrong9645

5 ай бұрын

They are fun, but if your goal is playing, you're much better with 2 d6s, if only because you can easily use them as 1d6 if needed. Plus you probably already have plenty of them already. Heck, people who don't know what ttrpgs are probably already have plenty of them. You could argue that the d3 could also be useful, but then again, we all know how to make a d3 out of a d6. Of course, I'm not saying that to prevent you to buy them if you like them, just don't try to rationalize your purchase that way.

@kyzer422

5 ай бұрын

@@bobrong9645 That's true, but I bet you could design an rpg to specifically use these, like maybe the dodecahedron represents the damage you deal or your "hit location" or something.

@HalfpennyTerwilliger

5 ай бұрын

I actually have those dice in my dice pouch and use them everytime 2d6 comes up (greatsword damage in D&D for exemple).

I was under the impression that the edges of a 3D shape of constant width _couldn't_ be the same. I'd always heard so. Possibly in a Numberphile video even.

I made some dice that give me two random numbers between 1 and 8 and then I flip a coin to choose the higher or lower, and I use it to look for random book pages to make art from. So I might make a number between 12 and 87 or if I added them together between 3 and 15, but they don't hit every number combination. For example I can't make 47 or 74 with my original set, but I did make two complementary sets that together can do every number between 12 and 87. They're a bit like those 'properly pointless' dice that make up the two 6s.

Beautiful!

Fascinating.

Anyone selling a Gömböc with a "20" on top of it? Asking for a friend...

I'm curious if theres a permutation of dice that has the same probability table as DnD stat rolls (i.e. 4d6 take away the lowest value). Might try to figure it out but if someone else wants to, please do

These Dice are awesome

I *SO* want the Rouleaux dice! 🤩

That’s stupidly simple yet mega genius at the same time.

The next level is perhaps to make the three answers received per roll actually describe a mathematical relationship?

The recast 2d6 are my favorite!

Haha, after all the weird solutions to nonexistent problems he's heard, Brady is almost outraged at the 2d6 thing 😂 Actually, it's the first one where I was like "oh wow, that's actually ingenious!" 😅

I am a math nerd and a gamer, but it was explicitly the math nerdiness that made me buy some of these dice.

Can you get all of your dice on mathsgear in the UK too, I've had real trouble buying your d48, letter dice and optidice

You can show the breakdown of the d3 + "d12" on the original 6x6 breakdown; group each row of 6 into two 3x1 blocks, and each 3x1 block is a fixed value on the "d12" plus the d3.

"I know a few math nerds" Sir, that's what the channel is about

I love Henry's work. It's always so wild and wacky and interesting in all the best posible ways. If only the shipping cost of the dice to europe wasn't so astronomical

bringing chaos to the tabletop shops

Those d4s are the most delicious-looking dice I've ever seen.

I may just so happen to be one of the few who fits in the categories of math nerd and tabletop gamer both. I am definately looking at the constant-width d4 I particularly am seeking to collect every isohedral shape in dice form (excluding the infinite families). Currently, among all such figures with opposing parallel faces, I am only missing the Triakis Icosahedron. Possibility of production and retail?

Just call the whole set "Chaos Dice"

4:40 Of course!

Statistically better off staying put on a campsite or walking around when a search party is looking for you? Monty Hall problem?

How do you account for the "weight" of the numbers - either if you add to the surface or conversely etch it - the number 4 requires more ink (or more hole) than the number 1?

@anophelesnow3957

5 ай бұрын

On their site they have 'Optidice' - "dice optimized for fairness by using numerals that are physically balanced ", I do not know the bias regular numerals make.

I have ordered a set. :)

Woah woah woah, you really saved the best for last. I was (almost) bored up until them dice of constant width at the end. Shut up and take my money. Immediately.

"Who is the market?" I AM THE MARKET 🤣🤣🤣 I love weird dice.

Let us know when the constant width D4 dice are available to purchase!

Those last ones are for making your game last longer by keeping you in suspense while they take forever to stop spinning.

As a tabletop player, those are some nice ass dice.

constant-width wonkel-engine-dice are nice for that extra utility. great caustics but only c2-tubler it, and never put it in a c3+ tumbler! 3-sided dice (that are not pencil/prism-shaped) alone sounds useful. the rest is just clever splitting of cube corners. of course those are dependent. surely, you can convolute a lot of dice-pairs wiedly, but that D3+D12 ==2d6 is just unnecessary, and the more you convolute anything, the faster you approach a normal-distribution anyways.

Why not roll a normal d12, and partition the possible results into 2s, 3, and 4s?

i mean... can this functionality of a d3 and d2 not be done with a d6? the evens for 2, odds for 1, 1,2 for 1, 3,4 for 2, 5,6 for 3?(and the d4 then is the d2 twice with each roll being a digit of binary of 4(tecnically 0,1,2,3 but as long as its equal 1/4 chances its fair game right?)) the advantage with the d6 is that it is cheap and also a d6 :) i do understand the appeal of unnecessary stuff.

Love @standupmaths product placement ha ha!

There's also the weighted average 6-sized die, used in various paper wargames over the years back in the 1960's and later. It was 2 - 3 - 3 - 4 - 4 - 5. Could use regular dice and just read the 1 as a 3 and the 6 as a 4.

For the constant width 4 sided dice, wouldn't it make sense to take advantage of the flatter "corners" to lay the numbers straight at the top instead of having to have them surrounding the corner in multiple copies?

@henryseg

5 ай бұрын

I think we felt that it was better to stick to the "traditional" d4 numbering. Although the "corners" are flatter, they're not as flat as where we put the numbers, so the cuts would have to be deeper, making the plastic weaker and maybe messing with the smooth rolling a bit more.

The mathematical justification for Sicherman dice in Wikipedia uses cyclotomic polynomials and generating functions to derive the result (I know 'cos I wrote it). A similar technique applies to other non-standard dice.

The $C^2$ smooth d4 looks like it's right practical. I'm not sure if I really appreciate it, or find it to violates the, "what are these weird dice that are useless" property in ways that I find disturbing. I want to get some though.

[raises hand] I bought the "recast 2d6" years ago.

It would be cool to make a 2 and 18 sided die that act like 2x 6 sided dies. Or even better, a single 36 sided die.

@paulfoss5385

5 ай бұрын

A 36 sided die would be neat, however 36 is not a factor of 48 (the order (size) of the full symmetry group of the cube including reflections) or 120 (the order of the symmetry group of the icosahedron), which would preclude anything nice looking. It would have to be a double cone type shape like the d10, but with 18 sides on each cone.

@HeavyMetalMouse

5 ай бұрын

For the d2/d18, we can get {1, 4} + {1, 2, 2, 3, 3, 3, 4, 4, 4, 5, 5, 5, 6, 6, 6, 7, 7, 8} as the numberings. The d36 would be fairly straightforward, as you just have a single die, with known desired frequencies. To get really weird, for completeness, a d4/d9 solution could be {1, 2, 4, 5} + {1, 2, 3, 3, 4, 5, 5, 6, 7}

@gfrank98

5 ай бұрын

You forgot the set of a d4 and a d9!

@Pystro

5 ай бұрын

@@gfrank98 The only fair d9 is an 18-sided trapezohedron. If you used a dice of that shape, why not have that d18 and a d2. And it's also kind of close to a 36-sided bipyramid.

@paulfoss5385

5 ай бұрын

@@Pystro Yes, though technically there would also be the nonagonal bipyramid, and family of skew in between shapes would also be acted upon by D9. And the dihedral groups are not the only family of subgroups of SO(3) which can have arbitrary factors, there's also the cyclic groups, which act on a ludicrous family of dice including the dice lab's sublimely unnecessary thirteen sided "roll a card" die.

You could theoretically do this with a D60, and replicate a d2. D3, d6, d10, d12, d20, and d30, but if would have to be huge to label it correctly

I'm loving solving these.

For the math behind the Sicherman dice, Google "cyclotomic polynomials".

I kinda want the recast 2d6 to use in PbtA games (table top role playing games where all the rolls are 2d6).

Are they not from the UK or the EU? Is there not an easy way to buy the dice from Europe?

Beautiful. For the last, constant-width dice, why not engrave the numbers on top only once, rather than "triplicating" them around?

nice book indeed

I seen your old video🥰

I saw the sign language dice on the website, I'd like to see some braille dice if that's possible to balance.

I think "recast" works because it's like you cast different shapes in the role of two cubes, like how when an actor gets switched out for someone else the role is recast :D

But are they "Lucky Dice"? - In our D&D group we have special damage dice. They were giant brass D6 dice and they were heavy enough to do real harm if you dropped them on your foot.