Exotic Matter

Yesterday I talked about the way soft SF treats the concept of antimatter, which is mildly irritating from a scientific perspective but interesting in terms of what’s projected onto it. I also briefly mentioned why the depiction of antimatter is implausible. You cannot have a mineral ore which contains just some antimatter, and matter cannot gradually transform itself into antimatter in more than minute amounts without exploding or otherwise spectacularly destroying itself. That said, antimatter is not actually that exotic. For instance, even bananas emit positrons due to their radioactive potassium content, and I’d be interested to know if fly ash also does so. However, positrons are not all there is out there in the peculiar matter stakes.

It’s probably widely known that protons and neutrons are made of quarks, the former being two up and one down quark and the latter two down and one up, glued together in the nucleus by pions and orbited by electrons, which are leptons. All of these except electrons are hadrons, being made of two or three quarks. Leptons, though, are different. They are not analysable into smaller parts and are truly fundamental, and there are various kinds, the most familiar being the electron. There are a dozen types of lepton, grouped into particles and antiparticles, meaning there are six matter leptons, including electrons, muons, electron neutrinos, muon neutrinos, tauons and tauon neutrinos. Tauons and muons used to be classed as mesons, but mesons are now thought of as pairs of quarks, intermediate between the mass of electrons and nucleons. The masses of hadrons is lower than the sums of their constituent quarks because part of their mass is converted to energy to keep them together.

Muons and tauons, though, are basically heavier versions of electrons. They aren’t “made of” anything, but are just “there”. Each lepton corresponds to a quark, which are also just there, although it used to be thought they were made of smaller particles called “rishons”, after the Hebrew word for “first”. Hence there are also six quarks, which can be paired off as heavier and lighter types. All of these particles taken together are called fermions, which are what “stuff” is made of. The other type of particle is the boson, whose rôle is to bear forces, including such things as photons, W and Z particles and of course the Higgs particle, but these are not part of matter as such.

Neutrinos were theorised to exist in 1930 CE to account for what happened to the extra energy apparently lost when a subatomic particle decays. They were detected in 1956, eleven years before my birth, and this gives me pause for thought. Neutrinos have no mass or charge, and are almost undetectable. They only have spin. Nowadays, when I hear about non-baryonic dark matter which is supposed to make up most of the stuff in the Universe, I feel it’s suspicious because it’s rather too convenient that there just happens to be all this stuff which can’t be detected by any conceivable instrument except through its gravitational influence, and yet I have no problem accepting that neutrinos exist, possibly because they were simply established before I was born and so part of the general background of things. What to make of this?

However, neutrinos are detectable, by huge tanks of dry-cleaning fluid buried underground. This is tetrachloroethylene. Very seldom, neutrinos convert an atom of chlorine-37 to argon-37, which is then detected after the tanks are purged with helium and the argon separated. Something similar can be done with gallium-71, which it occasionally converts to the radioactive germanium-71, and since this is denser than tetrachloroethylene I presume this works better because the chances of interaction are higher when atoms are more crowded. There are other ways of doing this, but for me this is sufficient since it corroborates the existence of neutrinos, which can’t be done with non-baryonic dark matter.

If it existed, non-baryonic dark matter would count as exotic, and it’s divided into hot and cold types. Cold dark matter is the most speculative, and to my mind the most ridiculous, because it’s supposed to be like ordinary matter to some extent, possibly forming into atom-like structures and even organised matter like planets and living organisms, although those last are way out on a limb and not widely accepted scientific opinions. Hot dark matter is fast-moving, and in fact quite similar to neutrinos in a way because it constantly streams through the Universe, presumably orbiting and being generally influenced by other mass, unlike neutrinos which travel near light speed.

But it doesn’t exist. If it did, it would count as exotic matter. I have my own solutions to the problem but I won’t be going into them here.

Another kind of exotic matter which is merely speculative and probably doesn’t exist is the magnetic monopole. This arises from the thought that just as there are electrically negative and positive particles, so there ought to be isolated north and south magnetic poles with no local correspondents. If magnetic monopoles did exist, they would form extremely dense matter compared to atomic matter, but it would be similar to atomic matter in that the monopoles would form the nucleus and electrons would orbit them, but in much smaller orbitals, making the matter much denser. For this reason it’s been speculated that magnetic monopoles may have sunk to Earth’s core and therefore not be detectable on the surface. There is in fact no observational or experimental evidence that they exist at all. However, one does sometimes hear of news that they’ve been detected or used. This seems to be hype, because these are quasi-particles like the electron holes I mentioned yesterday. They’re emergent properties of larger bulks of atomic matter which behave like magnetic monopoles would if they existed, but can be explained in terms of physics which doesn’t involve these apparently mythical beasts. They occur in spin ice, which is not ice but named by analogy with spin glass, which is not glass. Particles have an intrinsic spin to them which can line up or be haphazard and is connected to magnetism. Spin ice is a crystal composed of tetrahedra with atoms at the corners two of whose poles point into the shape and two out. If this is heated, single atoms out of the four begin to flip over, so that their magnetic poles face in opposite directions, creating pairs of apparent north and south poles isolated within the tetrahedra which can then move across the crystal separate from each other and increasing in distance from each other as if they’re isolated particles when in fact they’re just very long, thin magnets known as Dirac strings. This kind of monopole can be moved around, meaning that magnetic currents can exist in the same way as electric ones can, except that they will always be alternating rather than direct.

Quasi-particles turn up quite a lot in condensed matter physics. As well as magnetic monopoles and electron holes, there are phonons. These are to sound as photons are to light: particles of sound, as it were. Phonons are important in superconductivity, which is conduction of electricity at the speed of sound in the material concerned without resistance. Other examples are rotons, which are quanta of superfluid vortices, and excitons, which are combined electrons and electron holes. These are not exotic matter, but that doesn’t mean they can’t behave like it. For instance, if an electron can orbit a magnetic monopole, maybe it can orbit this kind of fictitious magnetic monopole too. Just a thought: it probably can’t.

Positrons are probably the most familiar form of antimatter which turns up in fairly familiar settings. For instance, there are electrical processes taking place above thunderclouds as well as below them which can involve the generation of positrons. Gamma rays are generated by electrons being deflected by air molecules, which then pass close to atomic nuclei and become positrons and electrons, which stream up into space. Positrons are also generated when radioactive decay occurs in the form of protons, which are positively charged, becoming neutrons. This happens with potassium-40, carbon-11, aluminium-26 and oxygen-15. This form of radioactive decay is employed in positron emission tomography, where a radioactive tracer is injected to image things like blood circulation and tumours. Oxygen-15 is an example of an isotope used for this purpose, and this is also, unsurprisingly, how bananas produce positrons.

I mentioned muons near the start of this post. A muon, along with a tauon, is essentially a very heavy electron, with a charge equivalent to an electron but a mass of slightly under 207 times that of an electron. It has a half-life of around two microseconds, which is unusually long for an elementary particle, of which only electrons are stable apart from the ones travelling at light speed which obviously would be because time doesn’t pass for them. Muons penetrate much further than electrons because of their mass, and can therefore be used to image the inside of objects which are relatively deeply buried or embedded. It apparently isn’t used for medical imaging, but muons can be used for room temperature nuclear fusion by acting as nuclear catalysts. Muons can be generated by accelerating ionised hydrogen, in other words protons, into fairly light nuclei such as carbon, to release pions which then decay into muons. They do need to be generated because they’re difficult to store due to their short lifetime.

Muons can orbit nuclei in the same way as electrons can, and this is the first kind of real exotic matter. Like magnetic monopoles, this kind of exotic matter is much denser than ordinary matter because muons are denser and orbit closer to atomic nuclei. This makes room-temperature nuclear fusion possible because the radius at which the orbital is located is two hundred times closer and collision can occur much more readily. However, it takes more energy to produce muons than this would liberate, so it’s useless, at least at the moment. Since the mass of a muon is 207 times that of an electron and that of a proton is 1 836 times that of an electron, this kind of atom, known as a muonic atom, is over 900 000 times as dense as hydrogen, meaning that a litre of it would weigh eighty-two kilos if it were a gas. It would also be ridiculously radioactive, decaying by beta decay. Muons can also replace individual electrons in heavier atoms, as with hydrogen-4.1 Hydrogen-4.1 is actually helium in that it has a helium nucleus, but hydrogen in the sense that it only has one electron and is unionised (or at least it was before Thatcher – goodness only knows what happens now!). A sufficiently heavy atom with an orbiting muon would significantly lengthen its lifetime because additional electrons move faster until they approach the speed of light, but it isn’t clear to me where in the atom such a muon would be located because with hydrogen-4.1 the muon is quite close to the nucleus. As for hydrogen-4.1, I’m not sure about this but I think it would be a superfluid, because this depends on whether a substance, nearly always helium of course, is composed of bosons or fermions. So this is hydrogen which can be a superfluid and is denser than helium. Superfluids do weird things like flow uphill and pour better through small holes than large ones. If hydrogen-4.1 is thought of as helium, this also means this is reactive helium.

The other way muons can form exotic matter is by becoming the nuclei of a hydrogen-like atom. Because muons, like electrons are negatively charged, either antimuons have to form the nucleus rather than muons or positrons would have to replace the electrons. This is known as muonium and is stable enough to have chemistry. There are known isotopes of elements which are less stable than muonium, although its own half-life is the same as that of the muon or antimuon itself at two microseconds. The size of the atom is close to that of hydrogen itself, and considered as an element it can be thought of as a particularly light isotope of hydrogen. In fact it would be the lightest known element at something like a ninth the mass of protium, which is ordinary hydrogen. There is a compound called muonium chloride, which does very little because it’s so unstable, but breaks down into chlorine gas and muons.

A number of other atom-like things can be made from subatomic particles. There’s muononium, where a muon and antimuon orbit each other, positronium, where a positron and electron do the same, and also a theoretical but never detected pionium, where two oppositely charged pions are in association, useful for studying the strong nuclear force.

The only trouble is, all of these, and there are others as well, are very unstable and break down in microseconds of even less. But there are other forms of exotic matter which are likely to be more stable, sometimes in a very unfortunate way. One of these is strange matter.

Strange matter has a misleading name. Strangeness is just the name of a property of subatomic particles when they are massive but form easily and decay slowly, carried by the third quark known as strangeness. The terminology used in nuclear physics tends to be very divorced from the same words used in everyday English. It may occur in the centre of neutron stars, which are themselves made of exotic matter in the form of neutronium, which I’ll come to later. It’s thought that under sufficient pressure, the very distinction between nucleons is lost and therefore there is a state of matter consisting entirely of quarks without them being separated into separate, larger particles, and strange matter is an example of this, made solely of strange particles. However, that mere smooshing together doesn’t necessarily make quark matter, which may consist of up and down quarks, into strange matter. If the density is high enough, strange matter becomes more stable than this state and quark matter would be strange in these circumstances. Hence it’s likely that some neutron stars have strange cores, but nobody is ever going to be able to encounter the stuff. However, there is a second rather worrying alternative to this view.

Sufficiently massive neutron stars, on the verge of becoming black holes, could consist of masses of strange matter several kilometres across with a thin outer layer of neutronium. Also, in some cases when a nucleus decays, it may become a small piece of strange matter, or when strange stars collide, similarly, larger, but still fairly small, pieces of strange matter may “chip off”. This second type is called a “strangelet”. Strangelets are mixtures of up, down and strangeness, and once they’re over about a metre in diameter they’re referred to as strange stars. Atomic matter contains no strangeness because protons and neutrons are more stable than neutral lambda and sigma baryons, but in bulk, strange matter may be more stable even when not under pressure, meaning that any atomic matter it encountered, such as the planet Earth, would become a strange star, which is incompatible with biochemistry, or much else for that matter. This was the worry people had about the LHC: that it could produce a strangelet which would convert the whole planet. This scenario is very like the false vacuum. However, it’s been pointed out that in all likelihood strangelets rain down on this planet the whole time anyway, and if it was going to happen it would’ve done so by now.

Neutronium is a less extreme form of matter which just consists of neutrons packed together and has a density of around a hundred thousand tonnes per cubic millimetre. Where neutronium exists, it amounts to an atomic nucleus of enormous size composed solely of neutrons, which when free would decay after about a quarter of an hour, but in the form of neutronium are stable just as in atomic nuclei. Below a certain size, and I’m not sure what it is, the strong nuclear force isn’t sufficient to hold neutronium together so there can’t be atomic nuclei made solely of neutrons, for example. A possible use of neutronium is to cause a gravitational field, but there are problems with this because for it to be at the level humans can survive, a neutron star would have to be millions of kilometres away from them unless they’re in orbit around it, in which case there would be tidal forces away from the centre of gravity. It would be far less manageable than the centrifugal imposition of gravity, and impractical for a spacecraft since it would involve moving a greater than a solar mass.

Quark-gluon plasma was in the news a few years ago as it was achieved in a particle accelerator. It was also the composition of the early Universe. Gluons are the bosons which hold quarks together in nucleons. Plasma might suggest a rarefied state but this is by no means the case with such a plasma. It can be thought of as matter which exists in conditions which are so hot that not only can unionised atoms not hold together but the very particles making up atomic nuclei can’t either, but when it existed the Universe was so small that it was also very dense. It’s like a sample of the early Universe, before protons and neutrons had even formed.

Near the start of this post, I mentioned tauons. These are even more massive and short-lived leptons, and like muons are likely to be able to form exotic atoms in various ways. For instance, they can orbit in conjunction with their antiparticles or form the nucleus of a hydrogen-like atom. However, tauons have a lifetime in femtoseconds, so the possibility of any chemistry is non-existent.

I was originally provoked into writing this by trying to imagine how a stable mixture of matter and antimatter could exist. There can never be covalent or ionic bonds between atomic matter and antimatter because the electrons and positrons would annihilate each other, but those are not the only ways atoms and subatomic particles can associate, as is illustrated by the existence of exotic atoms. The problem with these is that most of they are highly unstable. However, clearly matter can accomodate electron holes as quasi-particles, although these don’t annihilate electrons when they come in contact with each other. There are clathrate compounds which consist of cages of atomic bonds containing atoms or molecules without bonds with them, so the possibility of stored antimatter in the form of positrons might involve something like that. The positron would need to be equally repelled on all sides by positive ions, and these would have to be in a stable configuration, so a tetrahedral crystal like that of a spin ice might be an option, but it’s hard to imagine a situation where there could be such a suspension. It would, however, be possible to suspend antimatter in the form of plasma magnetically, so scaling that down, a substance containing tiny holes but consisting of a kind of foam of atoms with spin directed towards these holes could possibly store them in the cavities, but they’d have to get in there in the first place, so the prison would have to be built around them. The energy could then be released by removing atoms gradually, causing the positrons to be attracted to and annihilate electrons, either within the substance or beyond it. Once this process had started, there would probably be a chain reaction and everything would rush out. It would be a minor form of matter-energy conversion which would result in a plasma plus lots of liberated energy at around a thousandth of the mass. This is still a lot of energy, since a milligramme of annihilated energy from a gramme of substance is still nine terajoules, which is a fully-fuelled Jumbo Jet of energy. Hence the energy density would still be extremely high and the question is then of how much energy would be expended making that arrangement, assuming it worked. But it means, for example, that rather than providing a car with fuel or recharging it, it could simply contain a small amount of this matter which would last the length of the car’s existence. It would, however, need to be resistant to corrosion and have a very high melting point. Maybe it should be made of platiniridium.

Mind Over Antimatter

Illustrative purposes only – will be removed on request

Spoilers for Doctor Who’s ‘Planet Of Evil’, Buffy The Vampire Slayer’s ‘Normal Again’ and Space 1999’s ‘Matter Of Life And Death’ follow.

I’ve been watching a lot of old SF TV and films recently, and have now reached the mid-’70s. Well, I say that. What I’m actually doing is following Anderson productions through from ‘The Dark Side Of The Sun’ down towards the present, but that isn’t exactly my focus today because I’ve noticed two interestingly similar uses of a science fiction motif which don’t seem to make a lot of sense, one in ‘Space: 1999’ and one in ‘Doctor Who’: antimatter.

Antimatter is definitely not what it’s shown to be in either of these. Starting with ‘Doctor Who’, there’s the serial ‘Planet Of Evil’, whose air dates are 27th September to the 18th October 1975, and with ‘Space 1999’ (is there a colon there?), the episode ‘A Matter Of Life And Death’, broadcast on 27th November 1975. Hence these two are very close together. This could almost be titled ‘The Depiction Of Antimatter In British SF Shows of autumn 1975’. The weird thing about the two of these is that both of them make antimatter into something it absolutely is not.

I’m going to start with describing what antimatter really is, how it was discovered and so forth. The first hint that antimatter was possible was Paul Dirac’s 1928 CE paper ‘The Quantum Theory Of The Electron’ which pointed out that there didn’t seem to be any reason why electrons should have negative charge. They just did. Now there’s a device called a cloud chamber, which contains humid air almost at the point where it starts to form droplets of water in a fog, and this is used to detect subatomic particles, which leave vapour trails behind them due to upsetting the delicate balance of the conditions. Other, similar devices are bubble and spark chambers. If a magnetic field is applied through a cloud chamber, it unsurprisingly causes charged particles to curve in a direction corresponding to their charge, so for example α particles, which are doubly positively charged helium nuclei, will go one way and electrons, which are negatively charged, will go the other. At any time, cosmic rays are passing through the atmosphere, objects on Earth and Earth itself in the case of neutrinos, so any cloud chamber will detect various particles from those, although most are filtered out by Earth’s own magnetic field. Thus you get a wide “zoo” of different kinds of particles constantly raining down from space, including β particles, which are just fast electrons and can be bent by a magnetic field. At some vague and disputed time in the late 1920s CE, scientists began to notice that not only were there electrons, but there were also other particles which seemed to be exactly the same as electrons except for one thing: they bent the other way in a magnetic field. In other words, they were positively rather than negatively charged. These particles were dubbed “positrons”.

Since I’m primarily talking about fiction here, I’m going to talk about Isaac Asimov’s use of these in his “positronic robots”. Asimov’s robot stories are primarily about the ethics practiced by said robots, but there’s a blurry technical background to them in that they all have positronic brains. This is essentially technobabble, but the idea is that robots’ heads contain something rather like a computer (and Asimov’s first stories in this vein more or less predate the invention of the digital computer) made of platinum-iridium alloy which operates by the creation and destruction of positrons. On one occasion, Asimov comments “no, I don’t know how this is done”. Since his focus is on the Three Laws, this is just off happening to one side and is rarely the focus of his fiction, but one thing he does say is that a positronic brain cannot be made without conforming to those laws. However, the reason for this seems to be that they have been such a central part of the ethics of US Robots that in order to do so, one would have to reinvent the wheel, so it isn’t that there’s a fundamental physical principle that makes this impossible. That said, in one of his stories a human character is captured by an alien robot which also obeys the Three Laws to the extent that it, too, “cannot harm a human being or through inaction allow a human being to come to harm”, so it seems that whereas there is no physical reason why using positrons prevents a robot from acting unethically, it’s more like the utility and function of such a machine is fundamentally ethical, in the same way as, for instance, any light source is going to have to emit visible light to be worthy of the name, so there is a reason why they’re like that which is as immutable as the principle of using positrons, but it works on a different basis which is more social, perhaps related to Asimov’s other big concept, psychohistory.

Although all of this is very vague, it’s still possible to discern a limited amount of nebulous creativity around the concept, if it’s worthy of that name. Platiniridium, as the alloy is in reality known, has some real world features which communicate something about the situation. Their use signals that the positronic brain is of extremely high value, since platinum is dearer than gold. The two metals are among the heaviest, that is the densest, of the chemical elements, communicating that positronic brains are very weighty, i.e. important. Platinum also has the reputation of being shiny, so it’s bright, an attribute which can be used metaphorically for intelligence, and also a sense of high technology – a gleaming bright ultra-scientific future. I can’t say that all of these things were operating in Asimov’s mind when he thought of it, but they are all in there for a reader. Another less obvious aspect, bearing in mind that he was originally a chemist, is that the alloy is particularly unreactive and has a very high melting point, so it’s resistant to physical assaults, which is what constant bombardment with positrons would be. However, this can’t be taken far beyond the figurative realm because in fact there’s no reason to suppose, and nor was there in the 1930s, that platiniridium would be any more resistant to damage from positrons than any other kind of atomic matter. If significant amounts of positrons were moving through platiniridium alloy, they would increasingly ionise both elements, they would become oxidised and probably melt from the extreme heat generated.

There does in fact seem to be a way of building a valve-based positronic computer, and it would have certain advantages, one of which is that it wouldn’t need an external power source, but any such device would also be extremely radioactive and dangerous, so it could only really safely operate in deep space, and there’s no particular reason for doing so. Another area in which positrons could be said to have sort of come up is in the electron holes which allow transistors, and therefore microchips, to operate. These are the absence of particles behaving as if they’re real, but oppositely charged, so if there could be a form of matter allowing electrons and positrons to co-exist, this would be a genuine aspect of computing where they would have a rôle. However, Asimov was writing at a time before electronic digital computers existed as such. Colossus, the first stored-program digital computer, was built in 1943, three years after ‘Robbie’ was written. Also, although the possibility of antimatter had first been thought of in 1898, at the time he was writing, positrons were en vogue but other antiparticles had yet to be detected and were probably absent from even the scientifically-educated public consciousness, though of course not to actual physicists.

The key feature of positrons in this usage was probably their ephemeral nature, like that of thoughts in the conscious mind, and in general there is no complex set of ideas in his fiction to back this particular one up. In fact it’s rather unusual in that respect, as he was a professional scientist and often provided a lot of technical detail regarding such things. For instance, at around the same time he wrote a story about a spoon made of ammonium ions which looked exactly like it was made of metal but turned out to stink horribly and was therefore unusable, and this is based on the common observation that the ammonium ion, NH₄⁺, behaves rather similarly to an alkali metal such as sodium or potassium and could perhaps be made to form into a bulk metal in some way. This is speculative, to be sure, and doubtless impractical, but the scientific detail involved is considerable and important. Compared to that, his positronic brain is very vague. In fact, whereas Asimov is generally a hard science fiction writer, the only major exception being the usual one of allowing faster-than-light travel when he’s actually writing SF as opposed to fantasy, the positronic brain is more a soft sci-fi idea, more like a light sabre or a food pill than a robot (ironically) or an alien.

The concept was borrowed from his work into a number of others, including ‘Doctor Who’ and ‘Star Trek’. The earliest mention in the former seems to be in 1966, in the Second Doctor story ‘The Power Of The Daleks’, where a character erroneously speculates that the Daleks might be controlled by one. In ‘The Evil Of The Daleks’, broadcast the same year, the same regeneration attempts to implant the “human factor” into such a device, to be placed in a Dalek. Later, in the Fourth Doctor serial ‘The Horns Of Nimon’, a robot is understood to be controlled by a “positronic circuit”. In ‘Star Trek’, the android known as Data has a positronic brain, and the phrase “Asimov’s dream of a positronic brain” is used at one point as if it was a well thought-out concept with firm theoretical underpinnings, and also some sort of technological Holy Grail. In the ‘Star Trek’ universe, they’re supposed to have the ability to configure and program themselves in a way which would be impossible with electronic circuitry. What the concept does, insofar as it is one rather than just a vague idea, is create a non-existent type of technology which can have all sorts of things projected onto it without annoying plausible scientific facts getting in the way. I’d go so far as to say ‘Doctor Who’ does the same thing, particularly where the human factor is being induced into the Daleks using them. When asked about whether his robots were conscious, Asimov replied that they were, and ‘Reason’ certainly suggests that they are through the deployment of the Cartesian method of doubt by QT-1. If you believe that some objects are conscious and others not, as most adults in the West probably do right now, you are stuck with the problem of what could make something like a computer conscious, and his solution to that, and even more so that of ‘Star Trek’ and ‘Doctor Who’, is to posit the positron as a potentially perceiving particle. This is possible because it’s outside everyday experience.

Positrons are simply one example of antimatter, and moreover, one which managed to escape from the general science-fictional concept, possibly because although they are anti-electrons they’re only rarely called that. The wider concept of antimatter turns up particularly in the matter-antimatter generators which release energy to power star drives in all sorts of stories, and this, assuming antimatter can be manufactured in bulk, is an entirely feasible use, because the total energy locked up in matter and antimatter would be released if they came into contact with each other, usually creating an almighty explosion. This is what the equation E=mc² expresses, or rather, it expresses the quantity of energy present in matter. There’s enough energy in a single grain of sugar to keep the population of Melton Mowbray alive for life, and from this it can be seen that chemical energy is ridiculously inefficient. However, such a prodigious release of energy is potentially very dangerous, and this has been used in science fiction as well, in the form of the Total Conversion Bomb.

These are both relatively scientifically plausible ideas, and given that enough antimatter could be found or produced, both would be entirely feasible. They blow fusion power and bombs out of the water of course, and given that existing weapons of mass destruction are worrying enough, they may not be desirable but the fact remains that they probably could exist quite easily. But for some reason, in autumn 1975 two science fiction TV series ended up using the concept of antimatter in a really weird way which is completely alien to scientific theory and shows no signs of ever being realistic.

The first of these is ‘Planet Of Evil’, a Doctor Who adventure, with the classic Fourth Doctor and Sarah-Jane Smith lineup at the start of the Hinchcliffe era. I read the Terrance Dicks novelisation rather than the TV version, probably because I was watching ‘Space 1999’ on the Other Side! The Tardis picks up a distress signal from Zeta Minor, a planet on the edge of the Universe, over thirty thousand years in the future from whenever Sarah Jane comes from (see Unit Dating Controversy) in the year 37 166 CE. It turns out there’s an antimatter monster on the planet who is killing everyone, and is able to pass between this Universe and the antimatter Universe via a pool of antimatter, which is black and has no reflections. The Morestrans are a species or race whose sun is going out and they’ve arrived on the planet to mine antimatter ore, which will provide energy for their planet for generations to come. However, the antimatter is prevented from leaving the planet by the planet itself, and it also acts like the potion in ‘Strange Case Of Doctor Jekyll And Mister Hyde’ by gradually bringing out a primal, evil side in people.

To analyse this, antimatter in this does seem to share some properties with real antimatter in one way, sort of, in that it provides a prodigious source of energy. However, it isn’t clear that this is only because it interacts with matter, which is potentially just as good a source. It isn’t a property of antimatter specifically. Antimatter also seems to be “evil”. It opposes matter in the sense that it’s its enemy. In a sense this is also true, because matter and antimatter are each others’ enemies in that they annihilate each other, but here it’s more like matter is good and antimatter evil. I haven’t read Robert Louis Stevenson’s novella so I don’t know if he goes into what’s in the potion or whatever, but I suspect that antimatter here is largely a plot device to represent that potion in an updated way. The idea of antimatter being present in an ore of ordinary matter probably doesn’t make much sense, because if there were actual atoms of antimatter, there’d also have to be a way to prevent them from coming into contact with matter or they would immediately mutually wipe each other out. The idea that such a thing could exist somewhere “out there” depends on Einstein’s famous dictum that “the Universe is not only stranger than we imagine, but stranger than we can imagine”. This is clearly true, but there’s no reason to suppose that antimatter ore made largely of matter is possible at all. To me, it suggests some kind of electromagnetic suspension of particles in a cage-like crystal structure, and it might happen that positrons could be captured by positively charged ions in a rock. This raises the question of how close bits of matter and antimatter could get before they interact destructively, and this is an important issue because of the quantum mechanical implications of the probability of a particular particle being in a specific location. Given that, it seems that two pieces of matter and antimatter approaching each other would increase their probability of annihilation as they got closer, which also means there’s an issue regarding the speed of light. But all of this is beside the point because it isn’t about the properties of real matter and antimatter but what it means in this ‘Doctor Who’ story, which being based on the novella will presumably be to do with the potential for good and evil coexisting in all of us and in Victorian terms the hypocrisy of private actions and public appearances, which is likely still to have been valid in 1974, when I presume it was written, and of course today. Given our current hindsight and the likes of Savile at the BBC doing what he did, and this being kept quiet or just rationalised away, ‘Face Of Evil’ comes across in a more sinister way as almost a commentary on child abuse happening at the time. In this context, antimatter becomes the inner evil, secret, hidden side, and there’s also a sense of greed in wanting the power from antimatter ore and that power corrupting.

The location of the planet, at the edge of the Universe, is probably also relevant and in fact this is what I mainly got from reading it. The pool, mysterious and bottomless, is like a portal into a neighbouring universe where antimatter dominates. I get the impression that there’s a kind of “Duoverse” with a plane down the middle, with matter on one side and antimatter on the other, and that the two sides are in an uneasy truce. Zeta Minor is like a border checkpoint between two mutually hostile territories. There’s also the influence of ‘Forbidden Planet’ and therefore also ‘The Tempest’, and the Doctor does in fact quote Shakespeare in the story. The famous jungle set is clearly linked to the isle which is “full of noises”. The monster is thus very obviously Caliban, although the story is directly based on the film rather than the play and there are differences. The semi-visible monster closely resembles that in the film, and in the case of the Doctor Who story the semi-visibility is to do with it only being partly in our Universe, i.e. world, and incapable of reaching all the way into it, and therefore being essentially other-wordly. But the trouble is that I can’t go into much depth about ‘Planet Of Evil’ because of my unfamiliarity with it, and also with Shakespeare and Robert Louis Stevenson.

The other example is much fresher in my mind, as I only watched it yesterday. ‘Space 1999: Matter Of Life And Death’, and I think there’s no article in this title either, so it refers directly to antimatter having those fundamental qualities, or perhaps matter being life and antimatter being death. So far, the entire series of ‘Space 1999’ has seemed quite odd to me, being closer to space horror like ‘Alien’ and ‘Event Horizon’, and of course the children’s book ‘Galactic Aliens’, than science fiction or space opera. Then again, ‘Doctor Who’, particularly of the Hinchcliffe Era, has strong elements of that genre too, but because it wasn’t on the Other Side, I might judge it less harshly. Even so, ‘Matter Of Life And Death’ is a problematic episode among many of the same in the series, which however I’ll leave largely aside for a future date. If the viewer takes the idea that Helen Russell is simply being allowed to see things less apocalyptically after the calamity at the climax of the episode, it makes the whole of the rest of the series take place in her imagination. It’s very like the Buffy episode ‘Normal Again’, but if a series of such high quality is allowed to do that, so should ‘Space 1999’ be judged fairly. In any event, I’m not here to discuss the whole of that series in depth although it is worth remembering that this is very far indeed from hard SF at this point.

Here’s the plot: An Eagle reconnaissance mission has discovered an apparently perfect planet for human life, which is named Terra Nova. During their visit, their craft is struck by lightning, knocking both crew members senseless, and returns automatically to Moonbase Alpha. When it lands, Dr Helen Russell goes aboard to find a third person present: her missing presumed dead husband, mysteriously revived and present on a distant planet he never went anywhere near, as far as she knows. When taken to Alpha’s medical bay, their equipment is unable to detect heartbeat or any other vital signs and it also turns out that he only has a normal pattern of body heat when he’s in her presence. There is pressure to discover more about the planet and considerable enthusiasm to settle on it, so he’s injected with a dangerous stimulant drug. He’s monosyllabic and largely unresponsive to everyone after this except his wife, with whom he has a more involved conversation and others conclude that he is using her life force to sustain his own life. He’s taken to be questioned and says he can’t tell where he came from but can tell them the planet is dangerous to them. He also says that Terra Nova is inhabited, “but not in the way you think”, then dies when he hears they will go there anyway. After his death, his body begins to “reverse polarity” (it actually says that!), which is a sign that it’s going to become antimatter, and this is dangerous because of the release of energy which will probably destroy Moonbase Alpha when it’s complete. The corpse then vanishes, after shocking someone with a burst of energy. They land on the planet. All seems well at first, and in fact this scene of their arrival is one of the few in the series I clearly remember. Everything seems fine, with parrots, edible fruit, breathable air and potable water. Then the Moonbase fails and the entire satellite explodes, a landslide kills Koenig and Sandra goes blind. After all that, Helen’s husband appears again and tells her it’s all about perception and she can choose to see things the way they were.

This is a largely unsatisfactory story of course, partly because it’s in the “it was all a dream” category, which at least one other ‘Space 1999’ episode, and also an episode of ‘UFO’ also do, and this is really scraping the bottom of the barrel. It’s been seriously suggested that the writers were on acid when they came up with the idea, but leaving all that aside it’s still interesting to consider how it portrays antimatter. First of all, apparently a gradual transition from matter to antimatter is possible. Professor Bergman refers to “reversed polarity”, which I think is probably also a reference to ‘Doctor Who’, but also presumably means there’s an intermediate stage during which the subatomic particles making up the corpse only have some of their properties reversed, such as spin or charge, without being fully-fledged antiparticles. To be honest I do have some sympathy with the idea of there being particles preserving symmetry in other ways, but I get the feeling this is a very naïve view of physics, so I’m going to stick with the idea that it’s all or nothing: something is either a specific particle or its antiparticle with nothing in between. Otherwise it would be like saying something is slightly reflected. Alternatively, maybe it means that some of the particles have converted but others haven’t, which is again unfeasible as this would cause a huge surge of energy fuelled by mutual annihilation.

This episode is clearly inspired by ‘Solaris’, originally a story by Stanisław Lem and later made into two films (and an operating system). However, for some reason both films and the novel are so much better than this. ‘Solaris’ is extremely thought-provoking and lends itself to many interpretations. Its sentient ocean is replaced here by antimatter, which has a protean nature and is utterly alien. The idea seems to be that antimatter does not belong in this Universe but is able to mix with it to a limited extent, and is essentially mysterious and incomprehensible to us. The statement that the planet both is and is not inhabited is part of this. It corresponds to a wider sense of mystery and alienness found throughout the series. And of course, antimatter is once again metaphorical.

I can only presume that the concept of antimatter was topical at the time due to some kind of scientific breakthrough, which led to it being included in these scripts. Having said that, I do think the perception of antimatter is significant for both. The particle I think of as “gypsy”, also known as a psion or psi meson, was detected first in 1974, and whether it was valid or not there was also the idea that atomic matter included a small admixture of charmed matter where one of the quarks of a nucleon was replaced by a charm quark. This is not the same as antimatter, because there’s no fundamental incompatibility involved, but I don’t know if it’s actually the case or possible. My own impression of charm at the time was that it made some nucleons slightly more massive, causing matter to clump together in the form of galaxies rather than be spread smoothly throughout the Universe, but please remember I was only seven at the time and didn’t know much about nuclear physics. In any event, if this kind of mixture was a current idea in science at the time, the popular understanding of it might allow for the notion that there could be a metastable mixture of matter and antimatter which lasted more than a tiny fraction of a nanosecond but was still unstable over a short term compared to a human lifespan, and this mixture idea occurs in both works – the corpse in ‘Space 1999’ and the ore in ‘Doctor Who’. Both of them include a strong component of otherness in their idea of antimatter. In ‘Planet Of Evil’ it seems to be linked to ideas of horror and another universe at war with this one, which is kind of metaphorically true of matter and antimatter. In ‘Matter Of Life And Death’, antimatter is dangerous but also just utterly alien and beyond our understanding, and may also be linked to the idea of the Other Side in the sense of a spirit world beyond death. There’s an occult flavour to both of these.

On one level I find it quite annoying when scientific concepts are used like this. There doesn’t seem to be a good reason for using those specific ideas rather than something more fantastic and obviously made up which has no pretensions to a scientific basis. On another, I do have sympathy with it, because it attempts to express the essential mystery of what I might call “The Beyond”. There’s a very human projection here of fear of the unknown, but also sense of wonder, which is essential to science fiction. I’m not sure whether I’d describe either of these series as science fiction though.

One of the factors in play here is having to put series on screen for popular consumption. ‘Star Trek’ has this issue too, as do probably all TV series aiming for more than a niche audience. It’s like the limeflower tea sold in supermarkets which also has lime peel in it because that’s what some consumers expect. On the other hand, a character in ‘Space 1999’ itself makes an interesting point in another episode, that as time goes by a mythology for the modern age will be created, and it’s possible that this is what’s happening here. But we also have to live in a scientifically literate civilisation.

I’ve also noticed that I’m a lot more forgiving of technobabble and its consequences on ‘Doctor Who’ than I am on ‘Space 1999’, and I can’t help thinking that this is simply because the latter is on the Other Side. Maybe to me, BBC TV matters, and ITV antimatters.

The Anti-Universe

A prominent mythological theme is that of time being cyclical. For instance, in Hinduism there is a detailed chronology which repeats endlessly. Bearing in mind that the numbers used in mythological contexts are often mainly there to indicate enormity or tininess, there is the kalpa, which lasts 4 320 million years and is equivalent to a day in Brahma’s life. There are three hundred and sixty of these days in a Brahman year, and a hundred Brahman years in a Brahman lifetime, after which the cycle repeats. Within a Brahman Day, human history also repeats a cycle known as the Yuga Cycle, which consists of four ages, Satya, Treta, Dvapara and Kali. The names refer to the proportion of virtue and vice characterising each age, so Satya is perfect, life is long, everyone is kind to each other, wise, healthy and so on, satya meaning “truth” or “sincerity”, Treta is “third” in the sense of being three quarters virtue and one quarter vice, Dvapara is two quarters of each and Kali, unsurprisingly the current age, is the age of evil and destruction. Humans start off as giants and end as dwarfs. Then the cycle repeats. Thus there are cycles within cycles in Hindu cosmology.

The Maya also have a cyclical chronology, including the Long Count, in a cycle lasting 63 million years. Probably the most important cycle in Mesoamerican calendars is the fifty-two year one, during which the two different calendars cycle in and out of sync with each other. The Aztecs used to give away all their possessions at the end of that period in the expectation that the world might come to an end.

The Jewish tradition has a few similar features as well. Firstly, it appears to use the ages of people to indicate their health and the decline of virtue. The patriarchs named in the Book of Genesis tend to have shorter and shorter lives leading up to the Flood, which ends the lives of the last few generations before it, including the 969-year old Methuselah. Giants are also mentioned in the form of the Nephilim, although they are seen as evil. I wonder if this reflects the inversion of good and evil which took place when Zoroastrianism began, where previously lauded deities were demonised. There is also a cycle in the practice of the Jubilee, consisting of a forty-nine year Golden Jubilee and a shorter seven year Jubilee, and obviously there are the seven-day weeks, which we still have in the West.

The Hindu series of Yugas also reflects the Greek tradition of Golden, Silver, Bronze and Iron Ages, which was ultimately adopted into modern archæology in modified form as the Three-Age System of Stone, Bronze and Iron. The crucial difference between the Hindu and Greek age system and our own ideas of history is that they both believed in steady decline whereas we tend to be more mixed. We tend to believe in progress, although our ideas of what constitutes that do vary quite a lot. In a way, it makes more sense to suppose that everything will get worse, although since history is meant to be cyclical it can also be expected to get better, because of the operation of entropy. Things age, wear out, run down, burn out and so on, and this is the regular experience for everyone, no matter when they’re living in history, and it makes sense that the world might be going in the same direction. On the longest timescale of course it is, because the Sun will burn out, followed by all other stars and so on.

Twentieth century cosmology included a similar theory, that of the oscillating Universe. It was considered possible that the quantity of mass in the Universe was sufficient that once it got past a certain age, gravity acting between all the masses in existence would start to pull everything back together again until it collapsed into the same hot, dense state which started the Universe in the first place. There then emerge a couple of issues. Would the Universe then bounce back and be reborn, only to do it again in an endless cycle? If each cycle is an exact repetition, does it even mean anything to say it’s a different Universe, or is it just the same Universe with time passing in a loop?

This is not currently a popular idea because it turns out that there isn’t enough mass in the Universe to cause it to collapse against the Dark Energy which is pushing everything apart, so ultimately the objects in the Universe are expected to become increasingly isolated until there is only one galaxy visible in each region of the Universe where space is expanding relatively more slowly than the speed of light. This has a significant consequence. A species living in a galaxy at that time would be unaware that things had ever been different. There would be no evidence available to suggest that it was because we can currently see the galaxies receding, and therefore we can know that things will be like that one day, but they would have no way to discover that they hadn’t always been like this. This raises the question of what we might have lost. We reconstruct the history of the Universe based on the data available to us, and we’re aware that we’re surrounded by galaxies which, on the very large scale, are receding from each other, so we can imagine the film rewinding and all the stars and galaxies, or what will become them, starting off in the same place. But at that time, how do we know there wasn’t evidence of something we can no longer recover which is crucial to our own understanding of the Universe?

Physics has been in a bit of a strange state in recent decades. Because the levels of energy required cannot be achieved using current technology, the likes of the Large Hadron Collider are not powerful enough to provide more than a glimpse of the fundamental nature of physical reality. Consequently, physicists are having to engage in guesswork without much feedback, and this applies also to their conception of the entire Universe. I’ve long been very suspicious about the very existence of non-baryonic dark matter. Dark matter was originally proposed as a way to explain why galaxies rotate as if they have much more gravity than their visible matter, i.e. stars, is exerting. In fact, if gravity operates over a long range in the same way as it does over short distances, such as within this solar system or between binary stars, something like nine-tenths of the mass is invisible. To some extent this can be explained by ordinary matter such as dust, planets or very dim stars, and there are also known subatomic particles such as the neutrinos which are very common but virtually undetectable. The issue I have with non-baryonic dark matter, and I’ve been into this before on here, is that it seems to be a specially invented kind of matter to fill the gap in the model which, however, is practically undetectable. There’s another possible solution. What makes this worse is that dark matter is now being used to argue for flaws in the general theory of relativity, when it seems very clear that the problem is actually that physicists have proposed the existence of a kind of substance which is basically magic.

If you go back to the first moment of the Universe, there is a similar issue. Just after the grand unification epoch, a sextillionth (long scale) of a second after the Big Bang, an event is supposed to have taken place which increased each of the three extensive dimensions of the Universe by a factor of the order of one hundred quintillion in a millionth of a yoctosecond. If you don’t recognise these words, the reason is that these are unusually large and small quantities, so their values aren’t that important. Some physicists think this is fishy, because again something seems to have been simply invented to account for what happened in those circumstances without there being other reasons for supposing it to be so. They therefore decided to see what would happen if they used established principles to recreate the early Universe, and in particular they focussed on CPT symmetry

CPT symmetry is Charge, Parity and Temporal symmetry, and can be explained thus, starting with time. Imagine a video of two billiard balls hitting and bouncing off each other out of context. It would be difficult to tell whether that video was being played forwards or backwards. This works well on a small scale, perhaps with two neutrons colliding at about the speed of sound at an angle to each other, or a laser beam reflecting off a mirror. Charge symmetry means that if you observe two equally positively and negatively charged objects interacting, you could swap the charges and still observe the same thing, or for that matter two objects with the same charge could have the opposite charges and still do the same thing. Finally, parity symmetry is the fact that you can’t tell whether what you’re seeing is the right way up or upside down, or reflected. All of these things don’t work in the complicated situations we tend to observe because of pesky things like gravity and accidentally burning things out by sticking batteries in the wrong way round or miswiring plugs, but in sufficiently simple situations all of these things are symmetrical.

But there is a problem. The Universe as a whole doesn’t seem to obey these laws of symmetry. For instance, almost everything we come across seems to be made of matter even though there doesn’t seem to be any reason why there should be more matter than antimatter or the other way round, and time tends to go forwards rather than backwards on the whole. One attempt to explain why matter seems to dominate the Universe is that for some reason in the early Universe more matter was created than antimatter, and since matter meeting antimatter annihilates both, matter is all that’s left. Of course antimatter does crop up from time to time, for instance in bananas and thunderstorms, but it doesn’t last long because it pretty soon comes across an antiparticle in the form of, say, an electron, and the two wipe each other off the map in a burst of energy.

These physicists proposed a solution which does respect this symmetry and allows time to move both forwards and backwards. They propose that the Big Bang created not one but two universes, one where time runs forwards and mainly made of matter and the other where time goes backwards and is mainly made of antimatter, and also either of these universes is geometrically speaking a reflection of the other, such as all the left-handed people in one being right-handed in the other. This explains away the supposèd excess of matter. There’s actually just as much antimatter as matter, but it swapped over at the Big Bang. Before the Big Bang, time was running backwards and the Universe was collapsing.

In a manner rather similar to the thought that an oscillating Universe could be practically the same as time running in a circle because each cycle might be identical and there’s no outside to see it from, the reversed, mirror image antimatter Universe is simply this one running backwards with, again, nothing on the outside to observe it with, and therefore for all intents and purposes there just is this one Universe running forwards after the Big Bang, because it’s indistinguishable from the antimatter one running backwards. On the other hand, the time dimension involved is the same as this one, and therefore it could just be seen as the distant past, which answers the question of what there was before the Big Bang: there was another universe, or rather there was this universe. It also means everything has already happened.

But a further question arises in my head too, and this is by no means what these physicists are claiming. As mentioned above, one model of the Universe is that it repeats itself in a cycle. What we may have here is theoretical support for the idea of a Universe collapsing in on itself before expanding again. That’s the bit we can see or deduce given currently available evidence. However, in the future, certain evidence will be lost because there will only be one visible galaxy observable, and the idea of space expanding will be impossible to support even though it is. What if one of the bits of evidence we’ve already lost is of time looping? Or, what if time just does loop anyway? What if time runs forwards until the Universe reaches a maximum size and then runs backwards again as it contracts? There is an issue with this. There isn’t enough mass in the Universe for it to collapse given the strength of dark energy pushing it apart, but of course elsewhere in the Multiverse there could be looping universes due to different physical constants such as the strength of dark energy or the increased quantity of matter in them, because in fact as has been mentioned before there are possible worlds where this does take place. Another question then arises: how does time work between universes? Are these looping universes doing so now in endless cycles, or are they repeating the same stretch of time? Does time even work that way in the Multiverse, or is it like in Narnia, where time runs at different speeds relative to our world?

It may seem like I’ve become highly speculative. In my defence, I’d say this. I have taken pains to ignore my intuition in the past because I believed it was misleading. However, there appears to be an intuition among many cultures that time does run in a cycle, and the numbers these cultures produce are oddly similar. The Mayan calendar’s longest time period is the Alautun, which lasts 63 081 429 years, close to the number of years it’s been since the Chicxulub Impact, which coincidentally was nearby and wiped out the non-avian dinosaurs. The Indian kalpa is 4 320 million years in length, which is again quite close to the age of this planet. Earth is 4 543 million years old and the Cretaceous ended 66 million years ago, so these figures are 4.6% out in the case of the Maya and 5% for the kalpa. Of course it may be coincidence, and the idea of time being cyclical may simply be based on something like the cycle of the day and night or the seasons through the year, but since I believe intuitive truths are available in Torah and the rest of the Tanakh, I don’t necessarily have a problem with other sources. Parallels have of course been made between ancient philosophies and today’s physics before, for example by Fritjof Capra in his ‘The Tao [sic] Of Physics’. Although much of what he says has been rubbished by physicists since, there is a statue of Dancing Shiva in the lobby at CERN and one quote from Capra is widely accepted:

“Science does not need mysticism and mysticism does not need science. But man needs both.”