Sabbatical Travelogue

Volos 002Fantasy realized: sitting on a train, heading for a Greek port with a funky hotel waiting, working on my laptop. James beside me, searching a hotel for the next night on his phone. My fingers are still tender from starting to build calluses on the baglama we bought a few days ago in Athens. Rain showers pass by outside, wetting the green fields as we ride.

Yesterday I met with a couple of professors at the University of Athens. George Tombras is the chair of the Physics department, with a huge plate of challenge in front of him. 1500 students, 85 faculty (all “strong personalities”). 35 courses, 7 labs, and all students do a thesis. In the past four years an 80% cut in funding. Yes, 30% was not hard to absorb, but the other 50% has been painful. Couple that with the reality that only a few percent of their graduates can expect to find employment in physics. Over at the Technical University, the engineering graduates have an employment rate of maybe 15%. Think we have trouble with student motivation in the US? Yikes!

George and his assistant professor colleague Hector Nistazakis are exploring student conceptions of electricity and ways to increase the relevance of their courses. Our interests overlap in the area of how visualizations can be used. Hector also described his research on the use of wireless networks at optical wavelengths; dedicated building to building links for the ‘last mile’, the impact of atmospheric turbulence on signal attenuation, and how diffuse LEDs might be used for secure wireless transmitters in a room.

Our visit was on the Monday of their Easter break. Despite their difficulties, profs and grad students were working away, focused on what they do best.

Seeing into the heart

¬†Our visual systems are pretty impressive. Even when we are looking at images on a flat surface, our brains use all sorts of cues to create a 3D mental map. Shading on round objects helps, and of course the differences between what your right and left eyes see. If it’s moving, foreground objects will move faster than far field, and they’ll be larger (motion parallax). Shapes change as they rotate, and our brains interpret that easily. Occlusion, when an object passes behind another, is a big cue. Babies stop laughing at peek-a-boo when they figure that one out.

I’ve been spending a lot of time with my stereoscopic computer monitor, looking at flow in the right heart. It’s so complicated that even when I use lots of shading and occlusion, twisting and turning the representation, I still need the stereo cues to really see what’s going on. But it’s thrilling when I do.

So now I want to show it to everybody, but nobody else I know uses the 3D technology, even though it’s now dirt cheap (Thank you gamers!). So we’re back to motion parallax, shading and occlusion: it needs to move. The flow also needs to be simpler, so in this video, I’ve removed all the small velocities and vorticities, edited out almost all left heart and other extraneous flows, and tried to keep the colors from being overwhelming (although I love saturated colors).

Please enjoy this intro ride through the right heart. I hope to have more soon.