In This Short Film, The Macro Room Team Plays With The Diffusion Of Ink In Water And Its Interaction

How spheres impact water has been studied for more than a century. The typical impact for a rigid sphere creates a cavity like the one on the upper left - relatively narrow and prone to pinching off at its skinny waist. If the sphere is elastic –squishy – instead, the cavity ends up looking much different. This is shown in the upper right image, taken with an elastic ball and otherwise identical conditions to the upper left image. The elastic ball deforms; it flattens as it hits the surface, creating a wider cavity. If you watch the animations in the bottom row, you can see the sphere oscillating after impact. Those changes in shape form a second cavity inside the first one. It’s this smaller second cavity that pinches off and sends a liquid jet back up to the collapsing splash curtain. 

From the top image, we can also see that the elastic sphere slows down more quickly after impact. This makes sense because part of its kinetic energy at impact has gone into the sphere’s shape changes and their interaction with the surrounding water. 

If you’d like to see more splashy stuff, be sure to check out my webcast with a couple of this paper’s authors. (Image credits: top row - C. Mabey; bottom row - R. Hurd et al., source; research credit: R. Hurd et al.)

Manganese Dendrites on Limestone

Locality: Solnhofen, Bavaria, Germany

Another Ferrofluid representation

~ wikimedia commons

Stretching SpaceTime

According to general relativity, the sun’s mass makes an imprint on the fabric of spacetime that keeps the planets in orbit. A neutron star leaves a greater mark. But a black hole is so dense that it creates a pit deep enough to prevent light from escaping.

Image credit: James Provost  

‘Antique Adventures’ limited edition screenprint set

https://player.vimeo.com/video/129003674

Hannah Reber, "Fragezeichen V4", 2015, part of multiple-screen video installation

Hexagons and rhombis spreading out

Limited Short Term Memory Caused by Interference From Similar Items Seen Earlier

Our short-term memory is severely limited in everyday experience, but according to a new study from City, University of London and the Hungarian Academy of Science, it has no intrinsic limits when it comes to remembering information.

The research is in Psychological Review. (full access paywall)