Freaky Dot Patterns - Numberphile

Tadashi Tokieda is back, this time with Moiré Patterns.
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[@Brainiacs0]

I like how he has a knife and a block of wood, as opposed to, say, a couple of rulers.

[@Xezlec]

What, you mean you don't usually carry a knife and a block of wood?

[@jeupater1429]

With these numberphile vids and their random examples it always makes me wonder if they just don't prepare at all or if they're simply autistic (nothing against autism, it's a perfectly beautiful state of being)

[@justyo96]

@@jeupater1429 many brilliant minds fall somewhere on the spectrum! Also, studies have shown that children of high-IQ individuals are more likely to be on the spectrum - especially high-IQ scientists and mathematicians. Not saying Tadashi Tokieda is on the spectrum. I just find these facts interesting.

[@lostindixie]

@Reunite The British Empire Those studies aren't all that exact.

[@justyo96]

@@lostindixie I never said they were exact, I said they show a correlation. More research is definitely needed to say anything more about this topic.

[@some1rational]

"translations are just rotations with the center at infinity" - he said it only briefly, but I just had my mind blown xD

[@jesusthroughmary]

+some1rational 0:54

[@JustinShaedo]

+some1rational thank you I was distracted and missed this; you've made the risky choice of reading comments completely worthwhile.

[@theodorostsilikis4025]

than this would make rotations a sum of infinitesimal translations...

[@Bollibompa]

@@theodorostsilikis4025 Yes. You can measure the circumference of a circle with an infinitesimal ruler.

[@YualChiek]

Bernard Riemann: "Yep"

[@CBMaster2]

This explains the patterns I've been seeing all my life when two mosquito screen door overlap each others. Thanks!

[@anisulfatma8943]

Me too, always wondered.

[@sergiod.o.9476]

[Insert 'Confused Tom' Meme]

[@moonlightcocktail]

or in the electric fan when blades are removed

[@tomservo5007]

Professor "The photocopier is out of paper!" Faculty assistant: "I just refilled it yesterday." Professor : "Tadashi must be back from his sabbatical"

[@chromosundrift]

beats being out of shared computer time!

[@seanm7445]

When a grid’s misaligned, With another behind, That’s a moiré. ~xkcd

[@jessekendall8441]

when the spacing is tight, and the difference is slight, that's a moiré.

[@Fiddlesticks86]

😂

[@Aquillyne]

Ahaha

[@ErrantHippo]

now I want a pizza

[@trashmeme2328]

You should win the Best Comment Award.

[@Shilag]

Oh god, my eyes when the non-random spectrum started.

[@Minihood31770]

+StormGaming Yes

[@godminnette2]

+StormGaming Yes

[@JugglingAnusJuggler]

+StormGaming Yes

[@AntonAdelson]

+Shilag My brain!

[@AirAfter]

same

[@ultimateman1234]

"translation is like rotation with the center at infinity." How have I never heard this before? Mindblow.

[@jmedlin81]

this man's clarity of thought and speech is extremely impressive.. exceptional.

[@oz_jones]

And he's using a second (at least) language too!

[@dielaughing73]

Exactly what I came to say. Not a wasted word or incomplete thought in any of his utterances

[@jackfiercetree5205]

He makes toys and puzzles as a career. Very interesting man.

[@stevenmathews7621]

I'm a gate and fence manufacturer.. we got sheets of circular perforated sheets in a hexagonal pattern to clad some fences shortly after seeing this vid.. the offcuts were just thrown on the bench randomly (as you do), and I noticed the larger hexagonal pattern just walking by one day, so started playing with it (and of course showing my work-mates / boss). my fav effect was a whole heap on top of each other (could see the effect more clearly), and with the top 4 sheets, you make it so the top one makes really big circles with the 2nd sheet, and the 3rd sheet makes somewhat smaller circles with the 4th sheet.. you can only see the small circles that the 3rd makes with the 4th through the big circles that the 1st makes with the 2nd. Outside of the bigger circles (from the 1st and 2nd), you can't see the smaller circles ..very cool

[@corvusmonedulas4895]

no wonder my fence is taking so long to be built

[@Bazan_Studios]

Where can i see this?!

[@RoboBoddicker]

Awesome. You need to deal with this effect a lot in commercial printing. Since 4-color CMYK images are printed using grids of dots, if you just overlay all 4 grids at the same angle then the slightest offset will create Moire patterns. So you have to make the angle between the grids for each color maximally separated (at around 30 degrees), which makes very tiny "rosette" patterns that you can see if you look closely at a printed package.

[@antonhengst8667]

Very cool! Thanks for sharing!

[@brandon-butler]

This guy is awesome! Please do more videos with Tadashi!

[@T3hJimmer]

+Brandon Butler So much this! He bends my mind in such a delightful way!

[@woobmonkey]

+Brandon Butler All the yes!

[@insertnamehere6916]

+Brandon Butler Not as awesome as Cliff Stoll. Have you seen the klein bottle video?

[@brandon-butler]

***** Yes, I like this guy better. I wouldn't be afraid of taking a class with Tadashi ;)

[@insertnamehere6916]

Brandon Butler Well, I respect your opinion.

[@Baekstrom]

Only a mathematician will use the words “just” and “infinity” in the same sentence

[@darkfrei2]

Here was not complicated infinity, another one can be much more complicated. So, just easy infinity.

[@romaindubray2325]

6:22 his "just" doesn't refer to inifinity at all, but is rather used as "recently". Technically, you didn't say any different, and it feels like I just got clickbaited by a comment. Weird.

[@IrvingIV]

"I just thought it would be a quick stroll, until he dragged me along to the edge of infinity!"

[@opsimathics]

Tadashi you are blowing my mind,

[@TheShadowKitana]

Damn my eyes hurt

[@Minihood31770]

+StormGaming Yes

[@godminnette2]

+StormGaming Yes

[@MrRolnicek]

+TheShadowKitana But its still worth watcing.

[@JugglingAnusJuggler]

+StormGaming Yes

[@Ninth_Simplex]

+tothfirytoob My man!

[@ollllj]

moire patterns go very well with video compression, not.

[@numberphile]

+ollj oh definitely up your KZbin setting to HD if you are not already!

[@Luke__Whelan]

+Numberphile Okey dokey, I'll be back in an hour!

[@TGC40401]

+Numberphile I want to see this kind of thing in 4k. On second thought, I could just see it in real life. Hmm...

[@TheD1ddler]

+Luke Whelan Not even an hour, if I try to select anything more then 480p it will buffer over and over again for 20 minutes then will just stop with an error. Even in shitty resolution this was still an interesting video.

[@TGC40401]

+TheD1ddler I get 1080p. You may need to take action of some kind.

[@Checkedbox]

KZbin compression doesn't like this ;p

[@VeteranVandal]

+Joof KZbin "I hate randomness.".

[@Minihood31770]

+StormGaming Yes

[@godminnette2]

+StormGaming Yes

[@JugglingAnusJuggler]

+StormGaming Yes

[@Ninth_Simplex]

+tothfirytoob My man!

[@ben1996123]

i wonder how much larger this video file was than a normal video of the same length

[@Minihood31770]

+StormGaming Yes

[@shayan_ecksdee]

Still smaller than your mom

[@godminnette2]

+StormGaming Yes

[@JugglingAnusJuggler]

+StormGaming Yes

[@Creaform003]

+StormGaming Yes

[@oscill8ocelot]

That's it?! This video could be 30 minutes longer! =P

[@Minihood31770]

+StormGaming Yes

[@JugglingAnusJuggler]

+StormGaming Yes

[@TheTobyrobot]

+StormGaming yes

[@oscill8ocelot]

vavanade I wish. If only there was additional footage.

[@WhyAreHandlesAThing_]

+vavanade Or an infinitely long livestream.

[@ainsleyfan6926]

OMG its the foot guy!!!!

[@t3cchan]

+Fed480 what are you referring to?

[@RDSk0]

+Terry Martin One of the Mobius strip videos

[@ZeratulRahl]

+Terry Martin kzbin.info/www/bejne/fF63e5mng8R7eZI

[@Minihood31770]

+StormGaming Yes

[@godminnette2]

+StormGaming Yes

[@1ucasvb]

Tadashi Tokieda is awesome. I HIGHLY encourage people to watch his talk "Math Encounters -- Toy Models: Extracting Mathematical Surprises from Everyday Life", also found on KZbin.

[@deathtomorons9388]

He is also a polyglot.

[@nerdexproject]

"...the result is interestingly boring..." I laughed so hard! xD

[@UMosNyu]

This man is great! I like the topic he chooses and his overall style. Merry christmas to all numberphiles!

[@magicman9218]

Woops found the shape of the fabric of reality with two sheets of paper

[@TMGellert]

Numberphile 2012: Let's talk about special numbers! Numberphile 2015: Let's play with paper and transparencies!

[@jaiyeko]

Maths will always be maths

[@LittleLionRawr]

+Jay Eki Except when you're in the USA ;-0

[@jakedesnake97]

+T. Markus Gellert "If you think maths is only about numbers, then you must think that Shakespeare is just about letters." -The eccentric man from the glass Klein Bottle episode

[@TMGellert]

Jacob Raymond Cliff may be right but this is still NUMBERphile. Also he said "words", not "letters".

[@joshuajurgensmeier4534]

+T. Markus Gellert Well, after the infinity videos they kinda ran outta numbers.

[@OrangeC7]

4:50 I love the effect that's produced from him accidentally warping the transparency

[@LeeJamesORiordan]

Moire patterns appeared in my research on lattices in Bose-Einstein condensates, with a manuscript on the topic gone for peer review (browse playlists if you'd like to see). They are beautiful. Oh, and nice work!

[@raaziabacchus4703]

Yes! A new numberphile video! I was checking youtube constantly for updates. Amazing video as always! This channel makes me appreciate mathematics soo much more. Thank you!

[@dylanparker130]

love everything this guy does - his popular lectures for the LMS and IMA are amazing!

[@djdedan]

wait.. translation is just rotation with the center at infinity... mind blown.

[@MrJoker42369]

Totally had to make some patterns in autocad and print them out on vellum paper. So much fun to play with!

[@aresgalamatis7022]

Excellent episode, and a perfect presentation... a lot of food for thought, thanks!

[@alisonhansel9202]

This guy blows my mind! Definitely a new Numberphile fave. Looking forward to more videos with Tadashi!

[@sillysad3198]

i have noticed something. mathematicians are much more charming than physics on the brady's videos. they are very into the subject, very modest, never condescending, never smug...

[@deathtomorons9388]

Cause mathematics includes assumptions and physics is the opposite of assumptions. Assumptions are always fascinating.

[@j0nthegreat]

quite curious indeed

[@Minihood31770]

+StormGaming Yes

[@JugglingAnusJuggler]

+StormGaming Yes

[@jameswhyte1340]

Incredibly fun to watch. Thank you for making this. Mr.Tokieda you're inspiring.

[@KarbineKyle]

This guy is awesome! I'd love to see more of his demonstrations! Those demonstrations sort of reminded me of isomeric compounds rotating polarized light clockwise (dextrorotatory) and (levorotatory) anticlockwise! That's so cool!

[@mr.grenade8604]

“This one makes You seasick”

[@brianpso]

Wow this was really interesting! I really want more of this, I wanna know why does that happen with the triangles.

[@marverickbin]

i think its because the period of rotation of equilateral triangles is 60 degrees, and the square is 90 degrees.

[@Skibbityboo0580]

This man is an awesome teacher, and he is very soothing to listen to. I hope there are lots more videos with him!

[@johnchancey3941]

I can honestly say this was probably the coolest thing I've ever seen on KZbin

[@Gian990]

The asmr is strong in this man

[@bootblacking]

I get hella ASMR from Tokieda's voice.

[@TheNearFantastica]

+meadslosh same here. Also, he always shows some very interesting stuff.

[@subjectt.change6599]

This man is the most wonderful explicator of concepts you have yet had on this channel. Top marks!

A cameraman's worst nightmare...

[@MrSaemichlaus]

I encountered this phenomena while working with perforated sheet metal.

[@AmosFolarin]

That's awesome. It actually answers a question I've had since I was young - why you get concentric circles when you look at a street lamp through the branches of a tree without leaves... Thanks!

[@Timbalo0]

Great video. What i like about the videos with Tadashi Tokieda is the simplicity. I mean i could listen to Phil Moriarty talking about Entropy and Ed Copeland talking Dark-Quantum-String-weirdness all day, but i seriously like the style of his (Tadashi Tokieda) videos.

[@layalwazan]

This is awesome! I love things like this cause it makes you so curious as to what is happening

[@j0nthegreat]

a translation is a rotation with the center at infinity??? whaaaaa???

[@j0nthegreat]

+Bluelightzero hmmm, i suppose so. thanks.

[@Maxflay3r]

+j0nthegreat I mean, it sort of makes sense. If you have a plane with an object on it, and rotate the plane relative to a point somewhere on the plane, then the object moves along the border of the circle of a radius equal to the lenght of the distance between the center of rotation and the object in question. So the longer the distance, the longer the border, and thus the trajectory of the object becomes straighter. Thus if the center is at infinity, the distance between the center and the object is infinite, and thus the radius of the circle is infinite, which means that the trajectory is a straight line. Simply put, as the distance between the object and the center of rotation approaches infinity, its movement trajectory during the rotation approaches a straight line.

[@stijnservaes]

It blew my mind when we prove it in high school but it makes sense

[@leonhrad]

+j0nthegreat mind blown to infinity

[@godminnette2]

+StormGaming Yes

[@DodderingOldMan]

Man, I love this guy's accent... he speaks perfect English but with a cultured, educated Japanese accent that is instantly recognisable and distinctive.

[@deathtomorons9388]

He is a polyglot.

[@bcfblack]

Tadashi's videos so far have been some of my favorite numberphile videos to date!

[@moth.monster]

I'd like to thank you for the captions, because sometimes I struggle to understand people's accents. Lovely video.

[@PhilBagels]

O-ver-lapping designs make a pattern of lines, that's a Moire!

[@fijnman3813]

I need these in the house to mess with people's minds when tripping.

[@fearless1000]

Please make more videos with Tadashi, they are all fascinating and I find his explanations quite easy to understand.

[@droguk1]

simply amazing, something to try over Christmas

[@werrkowalski2985]

I gazed into the abyss, and the abyss gazes also into me.

[@ComputersAreRealCool]

This looks a lot better in real life, KZbin compresses the video (even in 1080p) which causes the patterns to not look as distinguished.

[@black_platypus]

+ComputersAreRealCool It wasn't so bad at my end... But yes, since you're imposing a regular grid (cells in the sensor and pixels in the video) onto this grid yet again, the effect will suffer. Same if you scan or even re-print an image printed with offset-print, for example. You can see the Moiré effect happening between printed dots and cells/pixels at 3:45 quite well :) That time, the undesired effect can be used to illustrate the contents of the video :D And with compression, there are different techniques, but many divide the picture up into fields of 8x8 pixels, for example.

[@sirstar45]

Thats one of the more amazing vids ive seen on this channel, wow!

[@RickySwan]

Excellent...! Love it. More please...!

[@yonjuunininjin]

I hope someone from numberphile give this man a pair of socks for christmas :D

[@HouseofKhaine]

4:21 This explains some of the artifacts I've seen when scanning a printed document. It's a slight rotation of scanned dots with printed dots.

[@jmendezsj]

Waked and baked and watched this. Best start to my day. Great visuals

[@CSAN33]

I love the videos with Tadashi!

[@rohanpandey2037]

I saw this (0:32) in a VSauce video a couple years ago about everywhere being the center of the universe.

[@black_platypus]

+Rohan Pandey Heh, same :)

[@tranngankim]

+Rohan Pandey yes they share the same idea

[@extremelysketchy4095]

+Rohan Pandey How can everywhere be the center of the universe if *I* am the center of the universe?

[@GEM4sta]

+Extremely Sketchy You're so big that you're everywhere.

[@sonnypruitt6639]

I'm glad I didn't meet this guy in 1970 while trippin on acid.

[@-yourandyoureare2different612]

Why?

[@thebarnyard5633]

*-YOUR and YOU'RE are 2 different words-* your acting out again

[@-yourandyoureare2different612]

@@thebarnyard5633 you're*

[@sonnypruitt6639]

@@-yourandyoureare2different612 U and R are 2 different letters

[@-yourandyoureare2different612]

@@sonnypruitt6639 and?

[@anssiaurum264]

Yes! We want more of this guy!

[@lawrencecalablaster568]

I like this! Thanks for coming back, Mr Tokieda!

[@lawrencecalablaster568]

Or rather, Mr. Tadashi

[@TakeWalker]

This is fascinating. I want to use this as the basis for a cyber-thriller or something. Patterns hidden in the dots!

[@AntonAdelson]

+Take Walker Have you ever heard about stereograms?

[@umcarainteressante]

+Take Walker Imagine being able to encrypt a complex map, hidden in an exact angle of rotation of two (or more?) layers of transparent dots.

[@TakeWalker]

Exactly the kind of thing I was thinking of!

[@umcarainteressante]

Take Walker If you ever do write something on this, please show us :D

[@TakeWalker]

Haha, man, I have to get over my fear of writing real fiction first. XD

[@adnanabbas.]

Your voice is so calming #Nohomo

[@TheSusej54]

without a doubt, my favourite numerphile presentor :) just the best :)

[@grantyale]

One can think of the transparency as a sampling pattern and the paper some signals. Plotting the patterns in the Frouier domain may explain the phenomenon more clearly.

[@PeteWall]

I think I need to describe more things as "interestingly boring"

[@Malandirix]

I need to reset my eyes by staring at a blank wall.

[@ninjaong87]

this guy is sooo mind blowing.. MORE MORE MORE!

[@joeeeee256]

This was absolutely fascinating!

[@thealbuzs]

what sorcery is this?!

[@lowe7301]

+Victor Aguirre He's a sorcerer! BURN HIM!!!

[@zelldot]

I expected more math behind it... this felt more like was just "this looks cool, let's just show them this"

[@CJCruiser]

even without numbers it is still math -- this is symmetry and euclidean transformation, just not quantized. He at least points out that triangular lattices are symmetric with 120 degree rotations xD and also introduces the concept of duals, which is big in geometry and group theory.

[@neropatti1504]

More Tokieda please! Arigato!

[@lpsp442]

Watching this hammered on Christmas day is the best thing EVER

[@GoldSrc_]

Brain.exe has stopped working... rebooting...

[@JoyFoxOfficial]

MY EYES!!!!!

[@seanisawesome000]

A found out about this a few weeks ago! It's cool that you're making a video on it now

[@sujitmohanty1]

Tadashi sir , no doubt one of the best!!

[@KustomKiu]

Numerphile can't post on the website a kind of dots that do that to us print out?

[@Minihood31770]

What happens if you try this with octagons or circles I wonder?

[@TheIslandwaters]

You can't really checker circles... As the intersecting point will become sides.

[@metallsnubben]

+Minihood31770 Yeah that's the problem (though you could certainly make patterns with them anyway) that you can't tile a plane using other regular shapes than squares, triangles and hexagons. BUT you could take weird irregular shapes and make stuff, or patterns of dots, the only problem is that you kinda need the pattern to have some manner of rotational symmetry for at least the moiré patterns to emerge :)

[@Theraot]

+Michael Nguyen "You can't really tessellate circles..." (fixed it) --- Somebody should do Penrose.

[@TheIslandwaters]

+Alfonso J. Ramos (theraot) I apologize. You are correct.

[@user-lw8qy8kj7c]

+Minihood31770 I was testing something similar to this a few weeks ago, although I used hexagons. If you rotate the top layer to the correct angle, you can see 6 pointed stars emerge. I imagine you'd get 5 pointed stars from tesselating pentagons.

[@garryiglesias4074]

Tadashi Tokieda, the only demomaker with paper, stencil and photocopier... No memory requirement, no dedicated GPU, no assembly trick... Just passion.

[@whiterottenrabbit]

Please do more of these videos wirh Tadashi, he's awesome!!!

[@stillltippin5758]

what is life?

[@fergusmaclachlan1404]

42

[@piotrdomagalski5096]

Pancakes.

[@-TKMAX-]

Don't hurt me

[@-TKMAX-]

No more

[@MrNacknime]

Does +StormGaming comment No below every comment?

[@pedrocavalcanti46]

+TG MrNacknime Yes

[@pedrocavalcanti46]

Just a regular troll, I find it quite funny, sometimes. Somewhere in the world, a dude is spreading "yes" and "no" on a math channel. But you know, I'm not Dr. House, so maybe I'm a moron too, hahahaha . (Sorry for my bad english)

[@bryanwan6169]

No

[@slendy9600]

+Pedro Cavalcanti your english was fine mate, even the punctuation.

[@tggt00]

+Pedro Cavalcanti Hi. (sorry for bad english)

[@janovewaldner1]

Finally, a Numberphile video with material I can understand !!

[@dcallstar51]

Tadashi is my favorite, I want to see more videos with him!!

[@marshmelows]

OMFG he sits just like L, the bare feet and all HAHAH

[@NoriMori1992]

+Migas Almeida Only for the first half minute though. XD And one of his legs was lying on the chair sideways under him, rather than both knees up to his chest. XD

[@marshmelows]

dude, but still awesome L thingy

[@NoriMori1992]

+Migas Almeida Ja! :P

[@ttykv]

Numberphile is better than LSD.

[@grigorbrowning]

More Tadashi please - or even more. I would love to attend lectures by him...

[@somedudeok1451]

Wow. Even as I child I was always curious about these types of patterns that emerge when you look through things like a meshed square trash bin. FINALLY someone showed me how this actually happens. Thank you!

[@shohamsen8986]

freaking amazing... especially the triangle one...

[@michaeltwiton2276]

Absolutely beautiful!

[@BunnyFett]

This is really fun! I love this speaker.

[@dancoulson6579]

I like this guy. He gives an impression of true wisdom.