Math Mutation 73: The Future That Never Arrived If you've gone to Disney's Epcot center, or seen other visions of the future created in the 1950's and 1960's, you've probably seen a geodesic dome. These are the big domes made up of triangles, that were thought by many half a century ago to represent the future of architecture. They still do look cool, but never quite caught on, and most of us still live in rectilinear houses. What are these geodesic domes, though, and what makes them so interesting? In general a dome is an efficient design, as judged by the relationship of interior volume to surface area, since in three dimensions, spherical figures enclose the most volume with the least surface. A geodesic dome is built using a network of linear elements forming portions of great circles around a sphere, where a "great circle" is a circle like the equator that has a diameter equal to the sphere itself. The intersecting network of great circles forms a large number of triangular elements. The most important property of these geodesic domes is that these great circles distribute stress across the structure, making them naturally very strong. However, due to the large network of intersecting elements, small flaws can cause stress to be transferred in very odd ways: Wikipedia references an incident where a snow plow bumped into one of these buildings in Princeton, New Jersey, and the damage appeared on the opposite side. But properly built domes have been seen to stand up extremely well against earthquakes, hurricanes, and other risks. Since this self-reinforcing structure is inherently strong, if you do it right, it is apparently possible to build one out of very lightweight materials; in the show notes, you will see a reference to a scitoys.com site that shows you how to build one out of straws and gumballs. But you've most likely heard about geodesic domes more recently due to 'buckyballs', the 60-atom carbon molecules discovered in the last few decades that have geodesic-dome-like shapes. Their extreme structural stability leads to many potentially interesting applications, such as using them to contain and transport simpler molecules, including densely packed hydrogen. Buckyballs were named after architect Buckminster Fuller, thought to be the inventor of geodesic dome architecture. He certainly patented and popularized them, though there is some dispute about whether certain German designs from the 1920's technically beat him to it. Fuller led a successful but very unusual life. While he gained international fame from his exotic but extremely strong dome-shaped buildings, he attributed more universal significance to his geometrical observations. These included principles of close-packing spheres, tetrahedrons, and octahedrons, which he called "tensegrity structures", in addition to understanding geodesic domes. He considered himself not just an architect, but a philosopher, and believed that understanding the interdependent nature of these geometric structures would lead naturally to environmentalism, universal government, and world peace. He called this philosophy Synergetics, explained as "The integration of geometry and philosophy in a single conceptual system providing a common language and accounting for both the physical and metaphysical." I tried to read his long, ponderous book on the topic, which described this philosophy in detail, but didn't quite make it through. As Wikipedia states, Fuller often created "long run-on sentences and used unusual compound words (omniwell-informed, intertransformative, omni-interaccommodative, omniself-regenerative) as well as terms he himself coined." He also considered his own thoughts and actions so significant that he made an effort to document every 15 minutes of his entire life between 1915 and 1983, titling the resulting work the "Dymaxion Chronofiles". These files included items ranging from personal journal entries to dry cleaning bills. But the fact that he went off the deep end philosophically should not detract from his architectural achievements. So anyway, if these geodesic domes are so great, why aren't we all living in them in the 21st century? To start with, domes have some obvious downsides: the sloping shapes mean that you will have a lot of wasted areas without enough headroom to be practical living space. And most building materials come in rectangular shapes, so it's hard to build a dome without a lot of waste. And laws and regulations regarding things like fire escapes, windows, and electrical wiring are ill-suited to these structures, adding extra expense. Similar issues come due to the geometic conflict with commonly constructed furniture: where can you put a sofa in a dome without wasting the space behind it? None of these problems were enough to stop Fuller himself from living in one of his domes, of course, but the rest of us who aren't quite as rich as him have to consider these practical issues. And this has been your math mutation for today. References: