#reaction-diffusion system

[fuckyeahfluiddynamics]

Runescapes

Drying fluids can leave behind all kinds of fascinating patterns, as we've seen before with whiskey, coffee, and even blood. Here researchers study patterns left behind by lipids, dyes, and other fluids. (Image credit: M. Murali and L. Shen)

[fishdavidson]

Dream Journal 2017-09-25: The Sculpture Mystery House

Have you ever heard of the Winchester Mystery House? It’s a real place that was built by the wife of the guy who created the Winchester rifle empire. The house was under near-constant construction for decades, and has lots of weird and nonsensical architectural features (like stairs that don’t go anywhere). Legend has it that these oddities were there to confuse the vengeful ghosts of those killed by Winchester rifles.

In the dream, I worked in a place that was like a less-sinister version of the Winchester Mystery House. It was weird for no other reason than being weird.  There were floors with holes in them that led to secret tunnels, hallways that started off cavernous and tapered into a space barely big enough to crawl through, and no guarantee that a room would ever have an even floor. Hand-carved wooden sculpture decorated nearly every available surface in the house, except for one room that appeared to be a giant plastic slide. We would give tours to anyone who wanted to visit, and we always had a good number of visitors despite the house being located in the middle of a forest.

But one of the inconveniences of living in such an unusual house was that there weren’t any proper bedrooms. There was a warm and surprisingly comfortable place underneath the house where everyone would sleep. We would lay down on a patch of bare dirt, and various small animals would come snuggle up to us. A red fox and a horde of calico cats would make camp under the house with us nearly every night.

My favorite part of sleeping under the house was a phenomenon known as “Feline Delta,” which is what happens when 20-30 calico cats huddle together and the splotches in their fur align in such a way as to look like an image of a river delta from above. Because I am a super-nerd, my appreciation of this phenomenon was based on some real-life obscure math known as “Reaction-Diffusion Systems.”

I am not ashamed. Math is cool as hell.

---------

Header image is of the Minister’s Treehouse, which is supposedly the tallest treehouse in the world and was built in Tennessee.

[fuckyeahfluiddynamics]

One of the most beautiful chemical reactions is the Belousov–Zhabotinsky reaction, and it's the subject of the latest video from Beauty of Science. (Image and video credit: Beauty of Science; via PetaPixel; submitted by clogwog)

[144c]

[markusbenjamin]

Simulation of reaction-diffusion system.

There are three diffusing and reacting species in this setup, each controlling hue, saturation, and brightness of the pixels. The relationship among the species form an intertwined, loopy network:

In case you are interested in a longer take of the time evolution, I uploaded a video too.

UPDATE: although I uploaded a full HD, needle-sharp version, YouTube ruined it, I don’t really know why. If anyone knows a solution, contact me, it would be much appreciated.