Scientists and non-scientists alike have long been dreaming of elements with mighty properties. Perhaps the fictional materials they have conjured up are not as far from reality as it may at first seem.
The periodic table of elements has become one of the defining symbols of chemistry. It is, of course, a handy chart of the building blocks that make up absolutely anything and everything around us, but it is also the outcome of the work of a huge number of scientists, which led to the current understanding of the elements’ atomic structure and behaviour. For those who like organization, patterns and chemistry, what’s not to love?
Crucially, when Dmitri Mendeleev organized all the elements known at the time into a table that reflected similar properties, he left some gaps, thereby providing scientists with inspiration to fill in the blanks. The charm of dreaming about new elements was not, however, a pursuit reserved for scientists alone. Fictional materials have been cropping up in TV series, films and books for many decades, some taking on properties that could only ever exist in the fictional world, whereas others — perhaps a surprisingly large number — mirror their real-life counterparts.
Most fictional elements seem to be metals or alloys, presumably because many of the items needed by adventurers and superheroes revolve around strength — they typically need tools and protection gear that is difficult to bend, break or dent. It is therefore perhaps not surprising that adamantine, or adamant (as a noun rather than an adjective, though conveying much of the same resolve not to bend or break) appears in a wide range of fictional tales. The name comes from the Latin adamas (or adamans), which itself comes from the Greek adamas or adamantos, meaning unconquerable. In fact, adamant and adamantine have been used throughout history to refer to any material with incredibly robust properties — whether fictional or real, including some gemstones and metals. Jewellers’ favourite allotrope of carbon, diamond, also gets its name from the same etymological root owing to its hardness.
In the ancient Greek tragedy Prometheus Bound, for example, unbreakable adamantine chains are used to bind Prometheus to the rocks, while in Shakespeare’s A Midsummer Night’s Dream the impenetrable Demetrius is called “hard-hearted adamant”. This hard element also features in Tolkien’s world, in which one of the three Elven rings, Nenya, was “made of mithril and set with a white stone of adamant”. As fictional metals go, mithril is, of course, also noteworthy. According to Gandalf in the first instalment of the Lord of the Rings, The Fellowship of the Ring, “All folk desired it. It could be beaten like copper, and polished like glass; and the Dwarves could make of it a metal, light and yet harder than tempered steel. Its beauty was like to that of common silver, but the beauty of mithril did not tarnish or grow dim.” In fact, mithril was so strong and so light that it was even used to make chain mail in Middle Earth.
Naturally, science fiction has been a driving force behind the invention of many fantastic elements. As superpowers became more and more elaborate, a new set of science building blocks had to be created to match the material requirements to support them. Adamantium, the almost indestructible coating of Wolverine’s famous skeleton and retractable claws, is named for its strength much like the adamants and adamantines of literature, but it is in fact an alloy of steel and vibranium — the fictional element that comprises Captain America’s shield (in fact, the shield seems to be entirely made of vibranium in the Marvel Cinematic Universe; MCU) and the woven fabric of Black Panther’s thin armoured suit. Real-life alloys do have the ability to combine properties and exhibit a wide range of highly desirable behaviours — stainless steel, for example, is highly resistant to corrosion, and nitinol, a nickel titanium alloy, displays both a shape-memory effect and superelasticity — and this is mirrored in the fictional world.
Vibranium itself has some very interesting properties. A rare element mined from a meteorite that landed in the fictional African country of Wakanda, vibranium is said to be (again) light but strong — “the strongest substance in the universe”, no less, according to the 2018 film Black Panther. Yet, despite this impressive description, is there any chance that vibranium could simply be another name for an element that already exists in real life?
Vibranium is strong in all senses of the word — hard to bend, hard to break and hard to dent or scratch. It is also very light; in the MCU, the creator of the shield, Howard Stark, claims that it is one-third as light as steel alloy. When used as a component of Black Panther’s armoured suit, it is described as a light mesh with the strength to withstand the impact of most weapons. In real life, one of the strongest — yet lightest — elements is titanium. Unfortunately the value of vibranium’s tensile strength, which can be seen as one measure of its hardness, is unknown, preventing a thorough comparison. But, similarly to titanium, its resistance to dents and scratches is incredibly high, having only ever been scratched by itself in the MCU, when Black Panther’s claws leave marks in Captain America’s shield. In terms of its density, vibranium beats both steel and titanium (Table 1).
Another notable feature of vibranium is that the energy of any impact is absorbed, rather than passing through it. Conveniently, this absorbed energy can also be stored and released at a later time, so the material acts as a capacitor. How this impact energy is later dissipated is not clear. Its conversion into another form of energy that can diffuse away seems the most logical route — and would go some way towards explaining the bright flash of light that is seen when Thor’s hammer hits Captain America’s shield, as this stored energy would be converted into light, and probably some heat and sound too. The ability of a material to spread a large amount of energy across itself, thus preventing an impact from travelling straight through it, is already observed in real-life woven materials such as Kevlar, which is used in bullet-proof armour. This material is not elemental, however, but a polymer, specifically poly(para-phenylene terephthalamide). There is another material that is strong and light that could, in theory, be used in bulletproof armour. It can rapidly transfer heat and electricity with a strong vectoral preference for in-plane, rather than through-plane, transfer. It is elemental, as it is an allotrope of carbon, albeit in one of its rarer forms — I am of course referring to a scientist’s answer to (almost) everything: graphene.
Graphene1 is incredibly light, with a density of only 0.00016 g cm–3, yet amazingly strong2. It can also behave as a supercapacitor3. Direct comparisons show that graphene’s tensile strength is around 300 times that of steel and titanium — again though, unfortunately we don’t know the tensile strength of vibranium for a more accurate comparison. Owing to the strongly bonded carbons in graphene’s mesh-like structure (which is also reminiscent of the Wakandan wonder material used in Black Panther’s armoured suit), it would take a lot of energy to break the carbon bonds in graphene, so energy is more likely to be transferred across the material. Graphene’s hardness in terms of resistance to indentation cannot be accurately measured4, so there is little point in comparing this to that of titanium or steel, and we have no other reference value for vibranium — although one website dedicated to materials’ data has attempted to add some figures to the MCU version of this fictional element5.
Graphene’s limitations lie in the challenge of creating large enough volumes cheaply and easily, its rather poor resistance to fracture, and the fact that adding layers gives highly ordered graphite — which retain some of the properties of graphene, such as high electrical and thermal conductivity and a high tensile strength, but to a lesser extent than a single sheet of graphene. For example, it starts to become brittle as it is layered up, which would not be useful in superhero-related applications.
Given these comparisons, despite some discrepancies in densities (Table 1), it is not unreasonable to consider that graphene may in fact be a real-life vibranium6. Certainly, one company is using graphene’s tubular cousins, carbon nanotubes, to create a material they have also called Vibranium, and which is a composite material containing these strong elemental allotropes. Inspired by the fictional element, Hyperloop Transportation Technologies plan on using their version of this super strong material made smart with additional sensors embedded within it to add a layer (or indeed two) of additional safety in pod vehicles for a high-speed transportation project7. They claim that their version of Vibranium is a composite that is 10 times stronger than steel, 2.5 times more rigid than aluminium and 2.5 times the tensile strength of carbon steel, and that it will be constantly feeding back diagnostic information about the pod throughout its journey.
This certainly isn’t the first time that fictional materials have gone on to inspire a real-life version. In fact, many scientific innovations8,9 have been inspired or driven by science fiction, from the tractor beams10 of Star Wars to the invisibility cloaks11 of Harry Potter. However, one franchise seems to have single-handedly paved the path for scientists to create a large number of new gadgets directly inspired by the show. This is, of course, Star Trek. Replicators foreshadowed the existence of the 3D printer, while communicators directly inspired the design of the first mobile flip phones. Personal Access Display Devices look and work just like the similarly named iPad, and the Dominion’s headsets and Geordi La Forge’s VISOR both inspired the development of Google Glass.
As well as inventing products, the show also created a range of new properties for existing elements, and new elements entirely. Transparent alumin(i)um is used in the windows of the fictional spacecraft USS Enterprise (and served to casually save a couple of humpback whales). To attempt to recreate this material12, and in particular its peculiar optical properties, scientists have had to delve into the world of ceramics. Two routes have been described to prepare strong and transparent aluminium-based materials. The US Naval Laboratory created a magnesium aluminate, known commercially as Spinel13. The compound, as a powder, can be pressed into a mould under high pressure before being heated; the resulting product shows a cloudy finish, but once polished it is both transparent and tough. A second material that has also been produced perhaps more closely resembles Star Trek’s version. Commercially sold as ALON — its name a nod to its constituents — aluminium oxynitride has a crystal structure similar to that of magnesium aluminate, but it is 15% harder. It is highly transparent and relatively low in density, compared to more traditional armoured glass.
There is also the confusingly named dilithium, which does not refer to Li2, two real-life lithium atoms covalently bonded together to form an incredibly electrophilic gas molecule. It is actually a fictional element of its own, 87Dt, and one that we are unlikely to be able to find here on Earth, owing to the fact that it breaks most of the laws of physics. In Star Trek, elemental dilithium has the atomic number 87, which in our world would refer to francium, but this is where the similarities end. When it is electromagnetically ‘energized’, dilithium is able to maintain separation between matter and antimatter within the warp core — the reactor that allows the crew and their ship to travel faster than light. Subsequently it is also possible to control the combination of matter and antimatter, which releases a huge amount of energy. While commuters on Earth may dream of a similar material, this element remains firmly in the land of fiction. Nevertheless, this approach to control a potentially explosive reaction has been used as inspiration to engineer fuels and control systems in fusion reactors14, such as the Charger-1 Pulsed Power Generator, and those could one day make space travel to far-flung planets possible with a much shorter travel time. Additionally the fictional trilithium, a by-product of warp drives — propulsion systems powered by warp cores — could inspire safety features in new fusion reactors too, owing to its ability to inhibit nuclear reactions.
Albert Einstein once said, “I am enough of the artist to draw freely upon my imagination. Imagination is more important than knowledge. Knowledge is limited. Imagination encircles the world.”15 Were it not for scientists and non-scientists inspiring each other to be more imaginative, to seek out patterns in knowledge, and to hunt for the missing puzzle pieces, scientific progress would simply not have happened in the same way. So let’s dare to dream about what else is out there, and continue to both enjoy imagining larger-than-life elements and expand our knowledge of real-life ones. Given that oganesson, the heaviest element that we have observed so far, is already acting strangely16, it is not unreasonable to imagine even heavier elements with even stranger properties, perhaps harnessing once again the potential for science fiction to turn into science fact.