 Dear Fellow Scholars, this is two minute papers with Dr. Karo Jona Ifehir. It's time for some fluid simulations again. Writing fluid simulations is one of the most fun things we can do within computer graphics because we can create a virtual scene, add the laws of physics for fluid motion, and create photorealistic footage with an absolutely incredible amount of detail and realism. Note that we can do this ourselves so much so that for this scene I run the fluid and light simulation myself here at the two minute paper studio and on consumer hardware. However, despite this amazing looking footage, we are not nearly done yet. There is still so much to explore. For instance, a big challenge these days is trying to simulate fluid solid interactions. This means that the sand is allowed to have an effect on the fluid, but at the same time, as the fluid sloshes around, it also moves the sand particles within. This is what we refer to as two-way coupling. We also note that there are different kinds of two-way coupling and only the more advanced ones can correctly simulate how real honey supports the deeper and there is barely any movement. This may be about the only place on the internet where we are super happy that nothing at all is happening. However, many of you astute fellow scholars immediately ask, okay, but what kind of honey are we talking about? We can buy tens if not hundreds of different kinds of honey at the market. If we don't know what kind of honey we are using, how do we know if this simulation is too viscous or not viscous enough? Great question. Just to make sure we don't get lost, viscosity means the amount of resistance against deformation, therefore as we go up, you can witness this kind of resistance increasing. And now, hold on to your papers because this new technique comes from the same authors as the previous one with the honey deeper and enables us to import real-world honey into our simulation. That sounds like science fiction. Importing real-world materials into a computer simulation, how is that even possible? Well, with this solution, all we need to do is point a consumer smartphone camera at the phenomenon and record it. The proposed technique does all the heavy lifting by first extracting the silhouette of the footage and then creating a simulation that tries to reproduce this behavior. The closer it is, the better. However, at first, of course, we don't know the exact parameters that would result in this, however, now we have an objective we can work towards. The goal is to rerun this simulation with different parameters sets in a way to minimize the difference between the simulation and reality. This is not just working by trial and error, but through a technique that we refer to as mathematical optimization. As you see, later, the technique was able to successfully identify the appropriate viscosity parameter. And when evaluating these results, note that this work does not deal with how things look. For instance, whether the honey has the proper color or translucency is not the point here. What we are trying to reproduce is not how it looks, but how it moves. It works on a variety of different fluid types. I have slowed down some of these videos to make sure we can appreciate together how amazingly good these estimations are. And we are not even done yet. If we wish to, we can even set up a similar scene as the real world one with our simulation as a proxy for the real honey or caramel flow. After that, we can perform anything we want with this virtual piece of fluid, even including putting it into novel scenarios like this scene, which would otherwise be very difficult to control and quite wasteful, or even creating the perfect honey-depri-experiment. Look at how perfect the symmetry is there down below. Yum! Normally, in a real world environment, we cannot pour the honey and apply forces this accurately, but in a simulation, we can do anything we want. And now, we can also import the exact kind of materials for my real world repertoire. If you can buy it, you can simulate it. What a time to be alive! This episode has been supported by Linode. Linode is the world's largest independent cloud computing provider. Unlike entry-level hosting services, Linode gives you full back-end access to your server, which is a step-up to powerful, fast, fully configurable cloud computing. Linode also has one click apps that streamline your ability to deploy websites, personal VPNs, game servers, and more. If you need something as small as a personal online portfolio, Linode has your back, and if you need to manage tons of clients' websites and reliably serve them to millions of visitors, Linode can do that too. What's more, they offer affordable GPU instances featuring the Quadro RTX 6000, which is tailor-made for AI, scientific computing, and computer graphics projects. If only I had access to a tool like this while I was working on my last few papers. To receive $20 in credit on your new Linode account, visit linode.com slash papers, or click the link in the video description and give it a try today. Our thanks to Linode for supporting the series and helping us make better videos for you. Thanks for watching and for your generous support, and I'll see you next time.