Penrose Unilluminable Room Is Impossible To Light

Steve Mould
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Penrose Unilluminable Room is a room with mirrored walls that can't be fully illuminated by a single point source of light. I thought I was the first person to build one but Action Lab beat me to it: esvid.net/video/v%C3%ADdeo-inMihNPjevM.html

Here's Nils Berglund's channel: esvid.net/u-NilsBerglund

Alex Bellos's elliptical billiard table can be found here: esvid.net/video/v%C3%ADdeo-4KHCuXN2F3I.html

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Ciencia y tecnología

Publicado el


18 may 2022






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Comentarios 1 660
Steve Mould
Steve Mould Hace un mes
Action Lab's video is here: esvid.net/video/v%C3%ADdeo-inMihNPjevM.html The sponsor is KiwiCo: Get 30% off ANY crate: kiwico.com/stevemould30
carlos rivas
carlos rivas Hace 15 días
You just need more lights, i know the principle but in reality, its not with more freaking light in the room.
René Casaña
René Casaña Hace 17 días
What if you make a giant Penrose room in order to film what someone in the dark zone is able to see
garet claborn
garet claborn Hace 27 días
it occurs to me that tesla valves are making use of this and perhaps a good corollary
Check my about section link
Read my name
Francisco Puglisi
Francisco Puglisi Hace un mes
@Marcos viste
zakaryreilly Hace un mes
Nice to see a real life Penrose "room" rather than a simulation. Love how you always make tangible demonstrations rather than just explaining theory
Pseuko Hace 4 días
A good teacher
Squeaky Bunny
Squeaky Bunny Hace 15 días
@Peter in my, admittedly, limited experience with action lab, action lab seems to assume everyone is dumb as soup. Overexplaining everything. Derek from Veritasium is a science communicater. Going outside and challenging people to get the right answer is totally harmless and doesn't imply in anyway that people are stupid or that he thinks that or that he makes them look like that. The fact some people in the comments judge the people on display in the video doesn't day anything about Derek himself and I think it's weird that you connect the attitude of some people in the comments to how you view Derek himself. I'll also admit I don't always agree with Derek. But it's a good channel and I wouldn't describe him as smug.
Nothing Realy
Nothing Realy Hace 22 días
Couldn't you just defeat the room with a bright enough light
Peter Hace 28 días
"The Action Lab" always struck me as a more humble version of Veritasium. I have always felt a bit skeptical about the Veritasium guy, because he seems to have a subtle smug attitude towards people who don't understand math and physics. It's hard to explain, I just sometimes get that vibe from him; I think it is because he seems to make people look stupid by showing a bunch of scenes where he asks questions that they cannot answer, and then gets everyone in the comment section to go like "lol these people are so stupid, I knew this in 1st grade" and so on.
Connor Gregory
Connor Gregory Hace un mes
It’s one of the reason I like his stuff
Mikáci Hace un mes
The weirdest thing is to imagine you sitting in a dark spot of that room looking towards an illuminated wall, but still seeing nothing at all but darkness, despite that the wall is being illuminated. Hard to imagine, but don't forget those walls are mirrors, and they reflect light only in specific directions, they don't spread it randomly. However it's really hard to accept this thought. Maybe it's worth putting a camera into a bigger model, so we could see, how does it feel and looks like to be in such a room.
Changer Hace 7 días
I don't think you would be able to see the illuminated areas from the dark area. You can only see via light entering your eyes, so if no light is reaching the part of the room you are in, then it's impossible for you to see anything.
Echelon Rank
Echelon Rank Hace 18 días
@Jesse Gardner post the results here if youre gonna do it, but i think you might have to use an optical industry specific simulation software to get even slightly close to the truth.
Jesse Gardner
Jesse Gardner Hace 18 días
I'd love to simulate this in something like Blender or Unreal Engine!
Lookup VeraZhou
Lookup VeraZhou Hace 27 días
Turns out the entire universe is a penrose room.
Echelon Rank
Echelon Rank Hace 28 días
@Monty Cantsin as above, so below. the topic is mouldy, mushrooms are in the dark, room is impossible to enlighten, etc.
Pyglik Hace un mes
Roger Penrose must be an amazing guy. He solved a mathematical problem, and instead of publishing the result in a paper, he turned it into a Christmas puzzle in a magazine.
Satyaki Sil
Satyaki Sil Hace 4 días
Penrose was also the guy who believed black holes cannot exist and ridiculed Chandrasekhar when he presented the Chandrasekhar limit for stars.
Mayank Choudhary
Mayank Choudhary Hace un mes
@Brian Sammond v
Pyglik Hace un mes
Reading through his Wikipedia page: "Oh, it's the same guy as the Penrose triangle, cool." "And the Penrose tiling as well, interesting." "Moore-Penrose inverse of a matrix, never heard of it." "Penrose-Hawking singularity theorems, what?!" "Penrose process, something about black holes..." "Penrose invented the twistor theory which maps geometric objects in Minkowski space into the 4-dimensional complex space with the metric signature (2,2)... I'll pretend I understood that..." "Penrose diagrams, how many thing were named after him?!" "Penrose interpretation about quantum mechanics and general relativity..." "The whole chapter on consciousness and of course Penrose-Lucas argument." "And he got a Nobel Prize "for the discovery that black hole formation is a robust prediction of the general theory of relativity" ." Yeah, he is an amazing guy.
James Hace un mes
I second the suggestion to look into his other work. I first became interested in him through philosophy of mind, but he has done amazing things in many fields. There are lots of very good videos of him giving lectures which are very accessible without being superficial, too-an accomplishment in itself, especially with the very high level mathematics, physics, etc. he studies. Between the breadth of his accomplishments and interests and his ability to explain things clearly and with some pleasant personality, he reminds me a lot of Bertrand Russell. In my opinion, he's one of the greatest minds in history. Coincidentally, I just learned today that he, along with his father, created the continuous staircase that M.C. Escher made famous. It seems that whatever you've learned about him, there's still another accomplishment of his to find out about.
Michael Kaliski
Michael Kaliski Hace un mes
Roger Penrose was the author of one of my school maths textbooks and that was 52 years ago!
Hannah Hace un mes
I feel like this room would be a perfect level in a horror game where you have a flashlight and everything is dark.
kazuki hashimoto
kazuki hashimoto Hace un mes
@Shiron ☘️good idea i can see that beeing like a horror puzzle game where you have to fidle around with lights yes. have a good day.
Shiron ☘️
Shiron ☘️ Hace un mes
@kazuki hashimoto wow you're the first person I've seen saying sorry in a ESvid comment section. Big ups to you man 👌 also yeah this looks hard to incorporate in a first person horror , but what if it was like a top view like among us and you can see you character and the shifting eyes lurking in the shadows
Hannah Hace un mes
@kazuki hashimoto thank you for your apology. I do see your perspective on the room, it would indeed be difficult for you to be close enough to the shadows to be worried about what’s in them.
kazuki hashimoto
kazuki hashimoto Hace un mes
@Hannah i understand i was just pointing out that it is a normal room iff youre the flashlight holding person the dark spots that the light wont reach will never be visible to you in your perspective, but im sorry i didnt want to be an ass.
Hannah Hace un mes
@kazuki hashimoto why are you being rude for no reason? The point is that there will always be dark spots where the horrors can hide. It’s just an idea that I thought was cool. It doesn’t have to be a perfectly fleshed out game mechanic that makes perfect sense, it’s just brainstorming.
NukeMarine Hace un mes
I'd love to experience what a live size version of the room would do with sound. Like, you have dead spots but how hard would it be to locate sound that you can hear.
Siyar Yamin
Siyar Yamin Hace 25 días
Not really much, sound travels around corners
M Dwabes
M Dwabes Hace 26 días
Go to the Museum of Science and Industry in Chicago. There is a room there you want to go to...similar thing, but with sound.
Peter 30
Peter 30 Hace 27 días
It's called backrooms, but yeah. I'd wanna know too :))
beeble2003 Hace un mes
It's actually obvious that the two "mushrooms" can be any shape. Whenever light reflects off the mushrooms, you can just treat it as a new ray of light that's originating between the two foci. Whatever direction that ray is travelling in, it will always stay between the foci. Since it doesn't matter which way the ray travels, it doesn't matter what angle that part of the mirror is at -- in other words, it doesn't matter what the curvature is. It doesn't even need to be curved.
Matthias Görgens
Matthias Görgens Hace 3 días
@batlrar Concave is fine, too.
beeble2003 Hace un mes
@batlrar Reflecting light into the other half isn't a problem, as it's started between the foci, so it can't get into the pockets, as you say.
batlrar Hace un mes
Any convex shape, if I'm not mistaken. A flat or concave shape would presumably reflect light into the other half, although it would stay out of the opposite two 'pocket' rooms for the simple fact that any path it takes is the reflection of what it would have done in the original section with the opposite curvature.
Jari Hace un mes
can it be a christmas tree (fractal)
rando man
rando man Hace un mes
It would be really cool to have a full size completely legit room just like this but with multiple lights and switches wired so that any time you flipped a switch only one light would be illuminated. I could see this having a unique use in a museum or something to literally bring to light certain areas of a room for an interactive experience
Eric Hace un mes
That original source is an amazing find, Steve! I wonder if any of the other puzzles are as fascinating?
Kim T
Kim T Hace un mes
It would be interesting to show real-life uses for this phenomena such as trapping sound waves for noise reduction or preventing sea waves hitting a harbour?
Matthias Görgens
Matthias Görgens Hace 3 días
@viguiry The work very differently.
viguiry Hace 27 días
It exists already with noise canceling headphones
Charlie Gosh
Charlie Gosh Hace 28 días
It seems you're suggesting a method for folding a wave back toward its source, creating a new wave that's 180 degrees out of phase with the next wave, creating a dead spot. The pair of waves automatically cancel each other. The problem would be that the waves would have to have the same frequency/wavelength, but most of them would already be so.
Jason Dashney
Jason Dashney Hace un mes
Breakwaters already do that. Don't forget that nothing will be perfect, as Steve explained in the video how a point source light will work a bit different from a wave.
The Action Lab
The Action Lab Hace un mes
Ha ha, great minds think alike. Great video!
18matts Hace 7 días
Love both channels
Nicholas Darryl H.
Nicholas Darryl H. Hace 7 días
@BeActive Behappy you don't even know the saying do you
J H Hace 19 días
@BeActive Behappy taking a crap on someone trying to humorous isn't _you_ being humble or noble either. 'BE HAPPY' in your title doesn't fit too well with your post
BeActive Behappy
BeActive Behappy Hace 27 días
Calling yourself great isn't very flattering, at least to others.
dan b
dan b Hace un mes
Great video!
NeatNit Hace un mes
In the excerpt at 7:53 it says: "The precise shape of the lower curve is unimportant but [...] **it must also be smooth and fit smoothly on the elliptical arc at P and S.**" The mushroom shape isn't smooth though. A smooth curve, for those who don't know, is basically a curve that doesn't have any corners. The more formal definition is that the derivative of the curve must be continuous, but that's not important. I wonder why Penrose thought the curve has to be smooth. It clearly doesn't - it doesn't even have to fit smoothly on the elliptical arc, best I can tell. However, maybe the smoothness gives it more properties that a non-smooth shape (e.g. the "canonical" mushroom shape, which has corners) does not? Maybe a smooth shape will even be able to contain *waves* in the desired region, rather than just rays/particles?
Dane Meade
Dane Meade Hace 9 días
The elliptical part of the mushroom is smooth and I think that's what he's referring to. It's obviously not differentiable, much less continuously so and *much* less infinitely so at the corners, but everything between the corners is fine. Also just as a nitpick, a smooth curve doesn't just have a continuous derivative but has infinitely many continuous derivatives (indeed it's enough to say that it has infinitely many derivatives since differentiability implies continuity)
Beaker_Guy Hace un mes
Was wondering that too. Call up Roger? Also wondering about a circular room... a circle being just an ellipse with only one focus....
NeatNit Hace un mes
@Flyzguy This is a bit anticlimactic, but apparently the question at 7:48 straight out demands a smooth shape. So I think the only reason he says the shape must be smooth is that the question said so.
Flyzguy Hace un mes
I wonder if the way he was modeling it at the time required smoothness for his proof to work?
naylene hess
naylene hess Hace un mes
i also had the same thought lol but i dont quite understand why but your explanation helped
Nove Productions Co.
You've just earned my like since you've mentioned The Action Lab's video. That says a lot of you and must be rewarded. Not every content creator is able to do that with such an elegance!
C T Hace un mes
So glad to see Nils’ channel featured here! I’ve been watching every single simulation on it the past year. They’re great!
R2Bl3nd Hace un mes
It's crazy that both you and action lab had this same idea in such a short time span. It's like the invention of calculus
TheSnowman Hace 29 días
@Plane 91 no it’s not. He was already editing his vid when he noticed action labs video
icantfinditdammit Hace un mes
@GG EZ is that what you heard him say during the hard cut to him editing, you know, after the video was conceived written and shot? You might wanna get checked out for a stroke.
R2Bl3nd Hace un mes
@Get on the cross and don’t look back 🙄
Refindo Azhar
Refindo Azhar Hace un mes
@vulkein nils berglund made a video about it around a month ago
batzzz Hace un mes
....remote viewing.....
Logan Crisp
Logan Crisp Hace un mes
Hey Steve, I love watching your videos! This made me wonder if you could make a quantum mechanical version of the Penrose room. Even though the particles could tunnel through the walls, they still wouldn't be able to reflect off of every single surface. I know this seems a bit outlandish, but I was curious if maybe we could develop something like that in the future. Obviously making the wall thicker would diminish the probability of the particles being able to tunnel through them, but that solution seems a bit boring and impractical for our purposes. Maybe a different solution is possible. This could even have practical applications for quantum computers, where scientists have been having difficulty preventing the electrons from tunneling through.
Leroytirebiter Hace un mes
I cannot recommend Nils' simulation videos enough, they are spectacular :)
Jason Yesmarc
Jason Yesmarc Hace un mes
oh my god thank you for posting this. I have been having the hardest time finding radial light demonstrations of this room. It's been driving me absolutely crazy. EDIT: Will also be checking out Action Lab's video too! The problem I keep finding is so many hits on Google explain what the room is, but very few people demonstrate it in action with realistic or high-count light rays.
Brassblitz Hace un mes
I wonder if this has application in bunker construction or designs interested in maximizing survivability? Explosive shockwaves are waves after all. Maybe simpler design considerations already maximize that protection though?
DanHarkless ﴾Halloween, theme parks, YTPs, & more﴿
MythBusters episode 191, "Trench Torpedo", had some beautifully visualized experiments along those lines. #162, "Running on Water", also looked at the topic.
jhsevs Hace un mes
Or car audio
pterafirma Hace un mes
The principle is kind of similar, the main difference being that giant (low freq) waves are more omnidirectional. Picture a massive pulse of air pressure, filling the volume - it wouldn't care about which way it's allowed to reflect. Look into acoustic design, and how a bass trap is made for music performance and recording. I'd bet it's a closer analogy to what you're aiming for.
Muonium Hace un mes
This is why we use a (cross-sectionally) ellipse shaped reflective space for the pumping cavity in solid state lasers. The heart of a sold state laser is a crystal rod doped usually with neodymium erbium or ytterbium and the atoms in the rod are pumped by absorbing light emitted from a high intensity xenon/krypton flashlamp also in the shape of a rod situated at the second focal point opposite the laser rod inside the ellipse. Almost all the light from the lamp therefore goes into the laser rod.
Nicholas Darryl H.
Nicholas Darryl H. Hace 7 días
@Mel O please do not cause resonance cascade
Karl with a K
Karl with a K Hace 12 días
@Ildarioon That's because you are an engineer and never experienced it. 😁
Ildarioon Hace 13 días
@Karl with a K I think you underestimate the number of really succesful engineers. Also, I personally wouldn't use bikini girls and yachts as my success metric.
Echelon Rank
Echelon Rank Hace 24 días
​@Karl with a K with all this tech floating around, who can be sure anymore whats more plastic the girls or the bracket
minij hooi
minij hooi Hace 28 días
That original source is an amazing find, Steve! I wonder if any of the other puzzles are as fascinating?
Rafi Kazi
Rafi Kazi Hace un mes
I’d buy you’re kids’ sandwich machine for a dollar! But for real, seeing your kids get excited for Kiwico was extremely adorable
frosty3579 Hace 25 días
I actually like when multiple creators cover the same topic. It gives different points of view and explanations so the subject is covered more broadly.
The Majestic Sea Pancake
Thanks for doing this, was just thinking about this a few days ago and was gonna spend this summer picking up coding, this was one of the things I wanted to play around with.
Fallen Hace un mes
I love the simulations Nils Berglund does! Great to see one of his featured on such a big channel!
Jet Hace un mes
Me too! I saw his name pop up and I was very happy! And then it popped up another 5 times... very glad to see him getting some more exposure :)
Steven L
Steven L Hace un mes
right! i was looking for this comment.
High Tech Redneck
Interesting-- as you laid out the concept, my first thoughts were of standing wave ratio in a radio antenna. Then as you moved the light source around I began to see an analogy for closed mindedness in all areas of our thought. Only with the light in the geometric center did the greatest illumination occur with the least unlit areas, both in size and distribution. An excellent analogy for Johari's window.
Le YASEP Hace un mes
Nils Berglund does amazing works !!! I'm happy he gets more exposure !
James Thompson
James Thompson Hace 2 días
6:00 Has that been experimentally demonstrated with Penrose? That looks a simulation PRESUMING that light travels as a wave. But light behaves both as a wave and a particle. There needs to be an actual experiment with probes placed in “dark regions” to detect any visible light radiation. That would be really interesting. Imagine how that could call the “double-slit” experiment into question as a special case of a more general phenomenon.
Tommy Robbins
Tommy Robbins Hace un mes
Hey Steve, just wanted to say that I love how accessible you make otherwise niche or relatively abstract phenomena. Your videos are some of the best this platform has to offer but you bring a level of humility to your work that I think is invaluable. Keep being awesome!
Wiktor Szymczak
Wiktor Szymczak Hace un mes
I love how Steve makes science feel real and usefull. Like i "know" that all science is useful and real but it often doesnt feel like that.
Frank Roquemore
Frank Roquemore Hace un mes
I’ve always wondered what it would be like inside that room. Like imagine walking around in the main open space of the room and if you cross an invisible line on the floor then everything suddenly goes pitch black
Falco Hace un mes
I love the idea that the mushrooms could be smaller versions of the room itself
David Kain
David Kain Hace un mes
What about sound waves in a room shaped like this, an environment for audio engineers? Which shape would be the optimal near zero reflection room, at the listening spot?
Anthony Nelson
Anthony Nelson Hace un mes
This shape kind of seems like the perfect shape for a book shop, cafe, restaurant or the like in which people love to go because it has those nice and cozy shadowy bits wherein one feels all tucked away.
Sho Am
Sho Am Hace un mes
Wow, Nils' unilluminable room simulation was the first video I watched of his! Look how far we've come!
bowen voowy
bowen voowy Hace 29 días
Another great video from Steve, but also many thanks to Nils Berglund. Those animations are simply beautiful!
Andrew Chapman
Andrew Chapman Hace un mes
This is exactly the sort of detailed and nerdy breakdown of the room I was hungry for after that Action Lab video, so thanks so much for still publishing it!
Alessio Salvatore
Alessio Salvatore Hace 29 días
I would love to see a 3d virtual model of this made with ray tracing. I think it would be interesting seeing it from the inside
Binky Hace un mes
For the shape of the mushroom curves, an intuitive reason why they can be any shape so long as they don't go above the focal points, is that any ray of light originating from anywhere on those curves will pass between the two focal points from below them. Since the ray would be coming from below and between the focal points, either it hits the outer wall and is reflected back between the focal points by nature of it bouncing off an ellipse, or it hits the other mushroom curve.
Emma Hace un mes
I keep coming back to your videos because of your practical demonstrations. It helps me picture and understands that concepts you discuss in amazingly helpful ways, even if I've heard of the concept beforehand
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Johnny Hace un mes
I was watching this video until 6:20 just waiting for the answer to why the light didn’t defract around the corners. I was expecting a mathematical explanation but was left with “it does.” I was beginning to rethink my understanding of light 😭
Christopher Georgia
It's amazing how he's able to make such simple explanations for such complex things. Keep up the good work 😀
DanHarkless ﴾Halloween, theme parks, YTPs, & more﴿
@Christopher Georgia Yeah, I've been through that too; quite disheartening. ESvid really ought to pop up a warning when you click Edit on a ❤'d comment that if you hit Save, you'll end up with a 💔.
Christopher Georgia
@Steve Mould thank you so much. That's awesome 😃
Steve Mould
Steve Mould Hace un mes
@Christopher Georgia It's back!
Christopher Georgia
Oh no I just realized that when I edited the comment I lost the heart ☹️ it makes sense because if it didn't, somebody could just make a really nice comment, get a heart and then change it to something really mean.
Mr.Death X
Mr.Death X Hace un mes
I don't think i quite understand his simple explanation
Lil Mike
Lil Mike Hace 23 días
Adorable children. 😀 I still get excited when I get an empty box. Thinking of the things I can make with it. I was never clever enough to design and build a sandwich machine though ☺️
Niko Hace 7 días
i just want to say that its parents like you that give me hope for this next generation. i can tell these children have room to ask questions, learn, grow, and be themselves. its a beautiful thing, and a lovely contrast to the "i dont know" and "be quiet" responses i typically hear from parents when they are receiving questions from their children while they are out and about.
Ben Goodwin
Ben Goodwin Hace un mes
I would think that light would emerge a little bit in every direction whenever it hits something, but I guess if it does, it's so little that some parts never appear lit Edit: you can see a little bit, and it's explained in the diffraction, neat
Stephen Atwell
Stephen Atwell Hace un mes
With fairly normal walls, what would be the most efficient way to light the whole room (eg 2, 3 sources) and with the best brightness in all places?
caveman Hace un mes
I've been following Nils Belgrund for a while now so it's cool to see him participating in a video like this :)
Wamlart Muse
Wamlart Muse Hace un mes
Yes the action lab is awesome. Thank you Steve for giving him his props. I seen this video & was like no!, he tryin to steel his thunder lol. But Steve came through with the name drop.
Rogério Costa
Rogério Costa Hace un mes
Steve is the best in explain things in a more intuitive way. That is a true talent.
Peetiegonzalez Hace un mes
I love this, I love the Nils Berglund crossover and even Action Lab's attempt at demonstrating it. Thank you all for educating us.
Stephen Bennett
Stephen Bennett Hace un mes
The first thing that occurred to me when I saw the room shape was, why does it have to be symmetrical around the horizontal? And sure enough, Penrose's original isn't. So you could do a similar example with just the top half of the room you created, and it would still be unilluminable. Also, shouldn't it be Penrose's Unilluminable Room, not Penrose Unilluminable Room? Don't be afraid of the apostrophe!
White Mage
White Mage Hace 29 días
@Anon That's only the case for plurals with shared possession--not names. _The rose's thorns_ refers to thorns on one, single rose. _The roses' thorns_ refers to thorns on multiple roses.
Stephen Bennett
Stephen Bennett Hace un mes
@Nathan yes, you're right. A light source in the upper region would illuminate area A and both areas B. I was too busy thinking about light sources in A and B!
Nathan Hace un mes
The one in the original magazine isn't entirely unilluminable, it has two regions (labelled A and B) such that a point source of light inside one cannot illuminate any part of the other, but the entire room can be illuminated from points outside of these regions.
Anon Hace un mes
@JimFC Gregg The plural of rose is roses so there shouldn't be much a problem with this double-z sound But when you have two s like this, often the second is dropped and the apostrophe put at the end. i.e. Penrose' Unilluminable Room But I think the one in the video title is correct for the other reason you mention.
JimFC Gregg
JimFC Gregg Hace un mes
"Also, shouldn't it be Penrose's Unilluminable Room, not Penrose Unilluminable Room? Don't be afraid of the apostrophe!" It's not fear, it's just a convention. In the case of Penrose, it's for ease of enunciation because there would be 2 "z" sounds in a row. Then there's the Penrose staircase. For other reasons, Wheatstone bridge, Erlenmeyer flask, etc.
Rubber Duck
Rubber Duck Hace un mes
Would be interesting to see a real life U-form shape from 1:23. In real life demonstrations it probably seems unilluminable too
tritri301 Hace un mes
If light and sound are waves it would be cool to try with an actual room and see if two people in the room would hear each other if placed in those spots.
MrTwisted Hace un mes
@6:15 so would this be a simple version explanation and further proof that space-time is a medium? And now it's time to build a full scale model of a Penrose Room, with mirrored walls and big spot-lights and lasers! Yes!
Ell Hace un mes
Don't stop yourself just because ActionLab did it! I would re-watch the same topic taught by a different teacher. You guys are both great!
Khalilah D.
Khalilah D. Hace un mes
Science ESvid has to be the best niche out there. I never know what I’m going to learn about each upload yet I’m never disappointed and this video is no different 💛🙏🏽
Masked Death
Masked Death Hace un mes
I like Science ESvid but for the opposite reason. I usually know exactly what I'm going to learn, and the content creators always deliver. No clickbaits etc., just exactly what I wanted to see.
TiagoTiago Hace un mes
It's funny how these "synchronicity" events are so common. Across history, there have been many inventions that were invented independently at around the same time, with the inventors not aware of each other's developments.
That automatic sandwich machine is the coolest! I was lucky enough to inherit a fairly valuable antique version of the “sandwich making box.” It’s from my great great grandmother side from Italy, made by a small luthier’s workshop in the 1600s… to help supplement their income when they didn’t have enough violin orders. however the toilet paper tube used as handles…. rotted away sometime ago, and it was also missing the original Tupperware lid to spread the jam. I’m hoping one day to find someone that can replicate the original parts. I think it might be the only example of such an old automatic sandwich machine, and I’m just impressed the corrugated paper board has held up this long. A true family heirloom 😉
Artur Piatek
Artur Piatek Hace un mes
Would this work as a room design to stop sound from reaching the corners? Could be used in a recording studio.
Peter Trainin.
Peter Trainin. Hace 25 días
Dear Mr. Mould, i have infinite respect for you. Question: would sound waves be equally excluded from.the blind spots?
Niels Kersic
Niels Kersic Hace un mes
Another great video from Steve, but also many thanks to Nils Berglund. Those animations are simply beautiful!
SpinDoc Hace un mes
Are there applications of this for sound? A soundproof room? Or for ocean wave barriers etc.
vbddfy euuyt
vbddfy euuyt Hace un mes
That's so great that your kids are interested in engineering. I wish I had been encouraged more and discovered my love of it earlier in life!
Karl with a K
Karl with a K Hace 25 días
The more I watch these science/math based replies the more I am inclined to never let my children go into science, as you might as well just open up a successful business to earn a living, rather than study for 10 years learning a bunch of stuff that someone that owns a business will simply pay you chump change to use to answer any question they command you too.
quesne -
quesne - Hace un mes
You can chain these rooms, and get an infinite number of dark areas. Another interesting observation is that a ray of light originating at a focal point will after a few reflections coincide with the major axis.
Lewis Siragusa
Lewis Siragusa Hace un mes
I’m having trouble conceptualizing what it would look like to stand in one of the unilluminated sections of the room. Would you be able to *see* the illuminated sections? If so, doesn’t that mean that light from the illuminated is traveling into the unilluminated section (your eyeballs)?
Battlesheep Hace 23 días
You would be able to see it, only because light is a wave and would be able to diffract out of the traps. Plus any real mirror wouldn't be perfect and would have some light reflect specularly
Bryan Wakefield
Bryan Wakefield Hace un mes
I think it might be interesting if you removed the dividers outside the focal point from the physical model so the light could go all the way around.
Paper Spock
Paper Spock Hace un mes
I wonder what applications of this might be. A passage to a darkroom, perhaps? I feel like this should also work with soundwaves, so perhaps a means of open air soundproof separation of different rooms? Also, the way waves from one nook end up in the other, perhaps a setup for a room where two people could talk despite being a great distance from each other?
James Lawry
James Lawry Hace un mes
The model used here works less well for sound since sound has much longer wavelengths than light, so the simple ray approximation is less accurate. Diffraction is very low for the short wavelengths of light. and is ignored in this approximation of the waves as particles bouncing off surfaces. But for sound waves, diffraction is much more noticeable. So the regions that are found to be dark here would be quieter but not silent in the audio case.
Alex FM
Alex FM Hace un mes
A part of me cried a little, when he drew the ellipse @2:49 and just before he finishes the knot disrupts the shape.😅I was totally mesmerized by the smoothness of the movement and then was suddenly reminded of the little problems of practical setups
Regdu Geht
Regdu Geht Hace un mes
I was going to build my room this shape, but when I discovered I'm going to need 2 light bulbs to light it up I will not.😁
The Red Rabbit
The Red Rabbit Hace un mes
Holy cow, I wish I had KiwiCo as a kid. I had to settle for cheap book fair grow your own crystal sets, and learning to build computers when it came to recreational science growing uo
Steve Laferney
Steve Laferney Hace 19 días
Steve, I would light the room with a point-source light by placing it at the center of the room as high as it would take to allow all areas to be lit. The only way to do it with one point-source light and nothing else. Cheers.
Dianna 🥂T[A]P Me!! to Have [𝐒]𝐄𝐗 With 𝐌𝐞
Nice to see a real life Penrose "room" rather than a simulation. Love how you always make tangible demonstrations rather than just explaining theory
Jop Mens
Jop Mens Hace 26 días
Cool, kind of like a Zen stone garden in a way haha - one of those very clever ones with say 7 large rocks that you can (symbolically) never all see at the same time.
Miguel Borromeo
Miguel Borromeo Hace un mes
It'd be interesting if there is a bridge that takes advantage of the acoustic properties of an ellipse. A highway runs beneath the bridge, but the elliptical ceiling just redirects all the sound back into the highway. Meanwhile, walkways running alongside the highway remain relatively quiet, and you can easily talk to passers-by on the opposite side despite noise coming from the highway.
Tj930 Hace un mes
Appreciate your videos, Steve. So much more intelligent and intellectually stimulating than most other videos on the Internet. Actually have to think 😉👍
James Hace un mes
His ability to explain things in an accessible but still stimulating and not superficial way is why I enjoy his videos. It's also something he has in common with Roger Penrose!
John Doe
John Doe Hace un mes
I've always wanted to see this demonstrate in actual space rather than virtually. Nice.
Nolan Peters
Nolan Peters Hace un mes
Steve the next step is to teach your children to weld so they can upgrade their creations to be more robust. It's a natural step that they're ready for
Rizuken Nekuzir
Rizuken Nekuzir Hace un mes
I'd like to see this used in a 3d cylindrical shape, where you rotate it along the y axis, and make the top light up but be at such a steep angle that you can have a hole in from above to look in, and the spot in the middle appearing as a black circle which seems like a bottomless pit but it's really not that deep. You'd probably need a way to block out light from outside the thing.
gregorysharp Hace un mes
High production value took you a lot of time. No way did you do this after Action Lab. Watch both. Love both.
Hi Hello
Hi Hello Hace un mes
I wonder how many points of light it would take to completely light up the room, might be interesting to find out. I don't think you would need to have more than 3-4 but could you make it work with 2? i don't know.
chi11estpanda Hace 26 días
Have you ever found the maker's mentality a curse? I was just taken aback to see you excited that they were excited to see a box and what to build something out of it. While I can understand the feeling of pride as a parent, I stare at the stack of cardboard boxes I saved to build something but never got around to. Hmm, in saying that I just realized, maybe it's not my maker's mentality but my procrastination that's the real curse... ...or more appropriately said, not a curse but a challenge. On another note, I was trying to make sense of how light illumination might be different than light than is observed. From what I can remember being taught, we see objects, or more specifically, we perceive objects by seeing the light that reflects off of it. So if you are sitting in one of those areas where light does not illuminate, sitting in the dark shadows, you could still see the light illuminate the areas beyond where you are. So what can be seen or observed is that light is there, but it does not reach in terms of illumination. This made more sense when you brought up how light travels in waves. So that leaves me to ask, what we're exposed to is not light illumination but light refraction? And is light refraction different than illumination? Or perhaps could it be said that the wavelengths of light that do make it into those areas are the wavelengths which don't give off energy but only exists as a trace of energy? Oh what a rabbit hole I'm about to start on searching the internet for answers...
Louise Lincoln
Louise Lincoln Hace un mes
I bet this could be used to make a really awesome optical illusion! 🙂
Dan Sheppard
Dan Sheppard Hace 23 días
Never seen a real life Penrose Unilluminable Room, though I've known about it for ages. That's great!
K M Hace un mes
I want to make a rave dance room based on this design so there are always dark corners to hang out in no matter where the light show lights go...
TheDoorKnob Hace 4 días
i imagine a hide and seek in a room like that where the lights switches place randomly and the seeker has a nerf pistol and can only shoot at who he sees and people have to run to the dark spots
Cleiton Oliveira
Cleiton Oliveira Hace un mes
A reverse of this is very useful. A room where the light always go to a specific point instead of never going there.
H Warner
H Warner Hace un mes
Really enjoyed your explanation of this subject. Yes, I viewed the other video yesterday but enjoyed your background information and research. Thinking about constructing mini golf ball hole similar to the billiard you showed. It will make the grandkids happy.
Francis Valmont
Francis Valmont Hace un mes
Hi Steve, is there a room similar to Penrose room where it can’t be reached by the sound wave instead?
Andy D
Andy D Hace un mes
I've always wanted a cube, mirror room with lasers and smoke and one of those gyro rides in the middle.
SlovenMalaphor Hace un mes
Thank you for releasing this even though Action Lab just covered it, as I refuse to watch Action Lab, and would have never known about this otherwise.
temporal teleporter
Hey Steve, the smile you get when you talk science, shows you love science. But the smile you get when you mention your kids is precious.
Eliös Hace un mes
Thanks for the visual... I've used that exact round billiard table in a museum over 30 years ago!
Mark Ebel
Mark Ebel Hace un mes
Could you make light particles spin like a snooker ball?
Demiurge Hace un mes
Love your videos, Steve. You have a joie de vivre about you that is extremely contagious.
D Money
D Money Hace un mes
The ellipse explanation blew my mind. That was very cool!
Joel Louzy
Joel Louzy Hace un mes
I took mechanical drawing my freshmen year of high school. At some point we had to use a square, a ruler and a compass to draw ellipticals. I don’t remember how it was done exactly. We had to plot 4 different points, adjust the compass twice and draw 4 separate arcs and then erase everything but the perfect oval. It was super fun.
Katie Barber
Katie Barber Hace un mes
is there a certain shape of light, without adding an extra source, that would eliminate this type of room?
REDVelocity Hace un mes
I did make a carrom table like this 16 years ago in my school mathematics project. I illustrated exactly this very property. It joys me so much to see this same thing here. 😊
Connected to Nature
Nicely explained. Simple to understand. Thanks for the video.
Memento Mori
Memento Mori Hace un mes
Those mushroom ends can be of any shape, but you said about the diffraction of waves, so my question is: What shape of those ends would negate diffraction the best?
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