“Ye cannae break th’ laws o’ physics, Cap’n!”
– Chief Engineer Montgomery “Scotty” Scott
In the Star Trek universe, plots abound which involve time travel, (matter) transporters, matter replicators (don’t get me started) – and of course warp drive. When you are dealing with a big volume of space, encompassing thousands of alien races, you need a way of getting from A to B in a useful amount of time. To put things in perspective, Voyager 1, launched in 1977, has travelled a whopping 135 AU (Astronomical Units) or ~2 x 1010 km, but this is less than 0.002 light years. Wheeling out the popular yard- (light-year) stick, our closest neighbouring star is Alpha Centauri, a mere 4.3 light years away. (I’m simplifying a little, as I don’t want to get distracted – Alpha Centauri is actually a binary pair with a third star, Proxima Centauri, a smidge closer to Earth, but it’s a lot smaller, and it doesn’t have the same cachet).
(As an aside, for those you remember, and care, the Motion Picture had at its literal and metaphorical heart V’ger, which was the fictional Voyager 6, upgraded by sentient machines and itself becoming sentient. Voyager 6 was launched in “the second half of the 20th Century”. The only way for the plot to work, because Voyager has to pass from mortal ken, is that it travels via a wormhole to the other side of the galaxy. If it were going at the same speed as Voyager 1 then it would be a mere 0.015 light years away from Earth by the time Bill et al are boldly going. Space is really, really big).
So, you need to get places fast – we might actually want to get to Alpha Centauri as it might just have an Earth-like planet around it. So you need a method of propulsion. If this were a purely physics post, then I’d dust off the popular ‘Twins Paradox’. Most people are so familiar with this though that I’m not going to go through the mechanics of this. The upshot, however, is that it is not merely enough to be able to travel fast, you need to do so in a way such that time flows for everyone (inside the ship and on various planets) at more or less the same rate.
Which brings us to D for Dilithium. Dilithium is so key to Star Trek that it became an essential plot point in the brilliant parody Galaxy Quest (By Grabthar’s Hammer!)*. Strictly speaking dilithium is Li2, but in the Star Trek Universe it is a hard mineral which is only rarely found in nature. A further conundrum is that dilithium is stated to be an element: on the periodic table that is shown from time to time it comes up as element 87, which to us is francium. There are two possible explanations. One is that the scientists of the future have a very different approach to the use of the periodic table and the form that we have been looking at is actually a form of inventory of usable elements/alloys. Alternatively, who knows where science has taken us in the future (apart from to the Final Frontier, of course). Hence, what we might be looking at is a series of very complex ‘modified’ atoms, some of which can turn up naturally. What we do know is that initially it was impossible to produce high quality crystals synthetically, but this problem was overcome sometime between The Original Series and Next Generation, which allowed for much bigger fleets to be built.
*Realised here as beryllium spheres: the parody is spot on, but the science is more flaky than a croissant.
The crystals are only a part of a complicated energy generation procedure (‘Electro-Plasma System’, EPS), but one of the more critical parts, hence the focus on this part of the engine room. The (Star Trek) theory is that the mineral structure can be energised in such a way that it can produce a complex electro-magnetic field structure that can be used to manipulate anti-matter (anti-matter again!) – the nature of the fields means that the antimatter never comes into contact with the crystals, but can be controlled and directed so that it reacts with matter in order to heat deuterium and form a plasma.
In a “that’s your problem with this?” moment, it should be noted that dilithium crystals need to be recharged periodically. Most notably this occurred in Star Trek IV: The Voyage Home, which required the crystals to be recharged in order that the Klingon Bird of Prey can return back to the future, to coin a phrase… What is not entirely clear is why this might be the case. There are situations where a mineral or chemical is consumed or leaks (e.g. refrigeration gases, particularly those found in car air-conditioning systems), but this should not be the case here – the crystal is energised and creates a field. It’s possible that over time the crystal structure becomes degraded due to mobility of the atoms, exacerbated by the energies involved, but simply putting the crystals in a nuclear reactor is not really going to help.
Given that there is widespread use of magnetic fields to control the flow of plasmas already, this seems like an inconvenient way of controlling the whole process. Should such a mineral exist (or be capable of being synthesised) it is not certain whether it would be capable of producing the effects described – but it’s fun pseudo-science, so what the heck.
Afterword: Researchers at the University of Huntsville are looking a potential propulsion system which came to light whilst I was researching this post. Whilst in no way a warp drive, nor yet ‘real dilithium’, it’s still an interesting read, and an example of how to get the press interested in your story.