# A Simulation That Looks Like Reality! 🤯 ## Метаданные - **Канал:** Two Minute Papers - **YouTube:** https://www.youtube.com/watch?v=VqeNSZqiBzc - **Дата:** 17.07.2021 - **Длительность:** 6:30 - **Просмотры:** 600,891 ## Описание ❤️ Check out Perceptilabs and sign up for a free demo here: https://www.perceptilabs.com/papers 📝 The paper "Solid-Fluid Interaction with Surface-Tension-Dominant Contact" is available here: https://cs.dartmouth.edu/~bozhu/papers/surface_tension_sfi.pdf https://arxiv.org/abs/2105.08471 ❤️ Watch these videos in early access on our Patreon page or join us here on YouTube: - https://www.patreon.com/TwoMinutePapers - https://www.youtube.com/channel/UCbfYPyITQ-7l4upoX8nvctg/join 🙏 We would like to thank our generous Patreon supporters who make Two Minute Papers possible: Aleksandr Mashrabov, Alex Haro, Andrew Melnychuk, Angelos Evripiotis, Benji Rabhan, Bryan Learn, Christian Ahlin, Eric Haddad, Eric Martel, Gordon Child, Ivo Galic, Jace O'Brien, Javier Bustamante, John Le, Jonas, Kenneth Davis, Klaus Busse, Lorin Atzberger, Lukas Biewald, Matthew Allen Fisher, Mark Oates, Michael Albrecht, Nikhil Velpanur, Owen Campbell-Moore, Owen Skarpness, Ramsey Elbasheer, Steef, Taras Bobrovytsky, Thomas Krcmar, Torsten Reil, Tybie Fitzhugh, Ueli Gallizzi. If you wish to appear here or pick up other perks, click here: https://www.patreon.com/TwoMinutePapers Or join us here: https://www.youtube.com/user/keeroyz/join Thumbnail background design: http://felicia.hu Károly Zsolnai-Fehér's links: Instagram: https://www.instagram.com/twominutepapers/ Twitter: https://twitter.com/twominutepapers Web: https://cg.tuwien.ac.at/~zsolnai/ ## Содержание ### [0:00](https://www.youtube.com/watch?v=VqeNSZqiBzc) Dear Fellow Scholars, this is Two Minute Papers with Dr. Károly Zsolnai-Fehér. I am stunned by this new graphics paper that promises to simulate three-way coupling and enables beautiful surface tension simulations like this, and more. Yes, none of this is real footage, these are all simulated on a computer. I have seen quite a few simulations, and I am still baffled by this. How is this even possible? Also, three-way coupling, eh? That is quite peculiar, to the point that the term doesn’t even sound real. Let’s find out why together. So, what does that mean exactly? Well, first, let’s have a look at one way coupling. As the box moves here, it has an effect on the smoke plume around it. This example also showcases one-way coupling, where the falling plate stirs up the smoke around it. ### [1:04](https://www.youtube.com/watch?v=VqeNSZqiBzc&t=64s) Two-Way Coupling And now, on to two-way coupling. In this case, similarly to the previous ones, the boxes are allowed to move the smoke, but the added two-way coupling part means that now, the smoke is also allowed to blow away the boxes. What’s more, the vortices here on the right were even able to suspend the red box in the air for a few seconds. An excellent demonstration of a beautiful phenomenon. So, coupling means interaction between different kinds of objects. And two-way coupling seems like the real deal. Here, it is also required to compute how this fiery smoke trail propels the rocket upward. But wait, we just mentioned that the new method performs three-way coupling. Two-way was solid-fluid interactions, and it seemed absolutely amazing, so what is the ### [1:59](https://www.youtube.com/watch?v=VqeNSZqiBzc&t=119s) The Third Element third element then? And why do we even need that? Well, depending on what object is in contact with the liquid, gravity, buoyancy, and surface tension forces need additional considerations. To be able to do this, now look carefully! Yes, there is the third element, it simulates this thin liquid membrane too, which is in interaction with the solid and the fluid at the same time. And with that, please meet three-way coupling! ### [2:31](https://www.youtube.com/watch?v=VqeNSZqiBzc&t=151s) Three-Way Coupling So, what can it do? It can simulate this paperclip floating on water. That is quite remarkable because the density of the paperclip is 8 times as much as the water itself, and yet, it still sits on top of the water. But how is that possible? Especially given that gravity wants to constantly pull down a solid object. Well, it has two formidable opponents, two forces that try to counteract it, one is buoyancy, which is an upward force, and two, the capillary force, which is a consequence of the formation of a thin membrane. If these two friends are as strong as gravity, the object will float. But, this balance is very delicate, for instance, in the case of milk and cherries, this happens. And, during that time, the simulator creates a beautiful bent liquid surface that is truly a sight to behold. Once again, all of this footage is simulated on a computer. The fact that this new work can simulate these three physical systems and their interactions is a true miracle. Absolutely incredible. Now, if you have been holding on to your papers so far, squeeze that paper, because we will now do my favorite thing in any simulation paper, and that is when we let reality be our judge, and compare the simulated results to real life footage. This is a photograph. And now comes the simulation. Whoa. I have to say, if no one told me which is which, I might not be able to tell. And I am delighted to no end by this fact, so much so that I had to ask the authors to double-check if this really is a simulation and they managed to reproduce the illumination of these scenes so perfectly. Yes they did! Fantastic attention to detail. Very impressive. So, how long do we have to wait for all this? For a 2 dimensional scene, it pretty much runs interactively, that is great news. And, we are firmly in the seconds per frame region for the 3D scenes, but look, the Boat and Leaves scene runs in less than two seconds per time step. That is absolutely amazing. Not real time, because one frame contains several time steps, but why would it be real time? That this is the kind of paper that makes something previously impossible possible, and it even does that swiftly. I would wager, we are just one, or at most, two more papers away from getting this in real time. This is unbelievable progress in just one paper. And all handcrafted, no learning algorithms anywhere to be seen. Huge congratulations to the authors. What a time to be alive! ### [5:35](https://www.youtube.com/watch?v=VqeNSZqiBzc&t=335s) Perceptilabs Thanks for watching and for your generous support, and I'll see you next time! --- *Источник: https://ekstraktznaniy.ru/video/13870*