The Disappearing Spoon

At the edge of the periodic table lie the highly unstable radioactive elements, including francium, which is so reactive that it only ever appears for a moment. There is an even rarer element, though, and finding it requires understanding the “island of stability” and perhaps revising the periodic table completely. Because some elements turn into astatine while undergoing radioactive decay, scientists can guess how much astatine exists in the universe. Strangely, astatine is actually more stable than francium, which is “so fragile it’s basically useless.” While scientists could never produce a visible study of astatine, a team led by Emilio Segrè did managed to observe it by injecting some into a guinea pig and studying what happened.

One would expect astatine to be even more unstable than francium, but in fact the opposite is true. This is due to the fact that astatine is one of the “magic elements” identified by Maria Goeppert-Mayer—elements that have extra protons or neurons and are therefore much more stable than one would expect. The part of the periodic table that contains these counterintuitive elements is called the island of stability. Scientists believe it is unlikely that they will be able to synthesize every element into a magic number by adding particles to the nucleus, but it is definitely possible to do so with at least some. This means that many new elements have yet to be discovered and the periodic table may get a whole lot bigger.

These new elements also seem likely to have totally new, unanticipated properties that deviate from the existing rules of the periodic table. Over time, Einstein came to distrust quantum mechanics because of its “probabilistic nature.” He also failed to coherently unite quantum mechanics with the theory of relativity, despite spending his whole career trying to do so. At the same time, the two theories work well together, and were both needed to discover the element named after Einstein, einsteinium. In other contexts, however, the theories clash. This could place a cap on what is discoverable via the framework of the periodic table. 

Scientists believe the last element will be 137 (it is provisionally called feynmanium after the physicist Richard Feynman). If elements beyond 137 exist, their electrons would necessarily have to be traveling faster than the speed of light, and the theory of relativity tells us that this isn’t possible. Some scientists believe that there is a “loophole” within relativity that allows special particles called tachyons to travel faster than the speed of light. This seems unlikely, though. At the same time, just because element 137 might be the last discovered element doesn’t mean that the periodic table is simply going to become “fixed and frozen” with no more information added.

If humans ever come into contact with aliens, the mode of communication most likely to be successful is the “language” of math and physics. At the same time, the version of the periodic table humans use now may not correspond to how aliens view the elements. Even from a human perspective, the table is somewhat arbitrary—it could be organized according to a totally different principle, perhaps one much better than the current system. In fact, there are infinite possibilities of what shape the table could take. Scientists have become very creative with these possible shapes, suggesting a solar system-style structure, a double helix, or even a Rubik’s Cube. The table could even become three dimensional, with anti-elements represented as well.

Even the ordinary periodic table might be drastically expanded, with new categories of element included. One of these new categories might be elements made of “superatoms.” This term refers to the fact that eight to 100 atoms of an element grouped together tend to behave like a single atom, imitating everything a normal, single atom would do to the point that they can be essentially “indistinguishable” from a sole atom. This also means that a superatom made up of one element can act like a totally different element. Matter that does this has been christened “jellium.”

The periodic table will likely also be revolutionized by quantum dots, which are also called “pancake atoms” because they are completely flat. The pancake periodic table looks very different to the ordinary one, because the atoms inside it behave very differently. Understanding of this phenomenon remains at a very early stage. The important thing to note is that the current iteration of the periodic table is still relevant and will likely be used far into the future. Yet Kean can’t help but wish he could fund research into the invention of all kinds of wacky tables. Who knows if one of them would correspond to what a hypothetical alien species has created in order to understand the elements—maybe it could even impress them.