Squarks, green peas and me: the small search for significance

Janet McAllister

 

Boy, did Copernicus give us an inferiority complex or what. Before he showed up, Europeans had successfully forgotten about the Greeks’ scary heliocentric ideas for 1800 years and instead knew that the universe was created simply as handle-with-care packaging around those at its centre: humans. The firmament was a surface wrapped around the earth, sandwiching us between ground and sky, and it – like everything else – was designed for our benefit.

But then in the early 16th century, Copernicus burst the earth-centric universe bubble by claiming Earth orbited the sun, thus shock-starting a slow shrivel of the West’s confidence that humanity’s place was privileged. We clung on to each “best case” scenario as long as we could, each one less attractive than the last. When our planet was no longer the centre of the universe then the sun was; when the sun was not, then the Milky Way took its place – as a “continent” galaxy surrounded by smaller, satellite “island” galaxies. We were looking for transcendence – surely there must be more to life than the chaos on Earth, surely our raison d'être must be illuminated by some extraterrestrial sign of status; we aimed to be “aristocracy of the universe”, as astronomer Arthur Eddington scorned in 1933. Although defeat of such grandiose aims was generally accepted by mid 20th century, it was not until the 1990s that the Hubble telescope gave us undeniable evidence that some of the faint wisps of light captured by our telescopes were not just far away dust clouds or very far away galaxies, but clusters of galaxies unbelievably far away, and certainly not deigning to orbit the Milky Way. It’s an exciting time for astronomy – in the last 20 years, we’ve seen multiple galaxies so far away that their light reaching us now was produced billions of years before Earth years even existed, in the infancy of the universe. We’re mapping “great walls” of superclusters of galaxies, and closer to home, are finding new planets and measuring the star-sucking “cannibalism” of the Milky Way’s nearest galaxy neighbour Andromeda. New phenomena are being discovered all the time – one of this year’s developments is the identification of extremely rare, small, bright green and busy star-baby factory galaxies nicknamed “green peas” (thanks to a “peas corps” of volunteers, the first to “give peas a chance”). Our horizons keep widening as the size and centrality of Our Place and Us is diminishing. We realise that the universe doesn’t possess a centre at all.

Now, in this International Year of Astronomy – 500 years after Copernicus resurrected heliocentrism and 450 years after the death of telescope pioneer Leonard Digges – the scientific term for “Earth is nothing special” is “terrestrial mediocrity”.1 Ouch – even the euphemism is harsh. We are tiny specks, whose size and lifespan may be closer to that of a bottom quark (which exists for a trillionth of a second) than to a galaxy’s (possibly 100 trillion years – if the 13.7 billion-year-old universe lasts that long). As charismatic astronomer Carl Sagan put it: “We find that we live on an insignificant planet of a humdrum star, lost in a galaxy tucked away in a forgotten corner of a universe in which there are far more galaxies than people.”

Far more galaxies than people! Not just far more moons, or planets or even stars. And yet – we’re lost by whom? Forgotten by what? Why do we want to be in the centre of things? Why does our place two-thirds of the way down a spiral arm of the Milky Way make us unimportant – and, more importantly, why do we care? Do we think some intergalactic party is going on, and we’re missing out because our Local Cluster of 30-odd galaxies is not big enough for some Universal Governor to insist that our inter-stellar lightphone reception be upgraded? (“Hey, Earthlings! I’m having a party in 1280 years {at time of calling}! If you jump on board your impossible speed-of-light ship right now, you’ll arrive in time. Love, your favourite red supergiant superstar Betelgeuse!”)

That we think our place in the universe is insignificant says as much about our perceptions as it does about Space. Size matters on this planet – I could go all Freudian on our collective ass about why. But does that value judgement apply off-planet? After all, stars are born when the smallest molecules start a nuclear fusion reaction. So why do we care that we have judged ourselves a random by-product of the universe, and not its prized inhabitants?

I think it’s because we are still hoping that outer space will give us meaning and transcendence. We once imagined the stars were the fires of the gods; now astronomy seeks meaning from the universe in two overlapping ways – finding a replacement for God and finding alternatives to God. The first way is a search for the absolute definition of Everything – it seeks a replacement for God in the elegant theories he was once thought to have designed. The goal of the second is not cosmic objectivity but practicality. It seeks what is “out there” that may enrich our lives, things that we as a species can perceive and interact with. Other sentient beings, perhaps?

The first way – God Replacement – includes the type of thinking that puts the universe in a “this way up” box. (It can be no coincidence that those Northern Hemispherians who first expounded the round Earth theory put themselves near the top of the sphere – unconsciously they still worried they would fall off the Antipodes into some abyss). Without thinking, we assume there is some external cosmic observer who is in an optimum position outside the universe to view how the whole thing works. This ghost of God haunting secular science – this holy spirit, if you will – sees galaxies of stars spinning around the possibly infinitely dense orbs of matter we imprecisely call black “holes”. He sees clusters of galaxies orbiting something (the ghost knows what it is, even if we don’t, yet), and the largest conglomerations of mass pulling on itself – superclusters of clusters. He agrees with this human-ordered hierarchy of matter: the galaxy, group, cluster and supercluster categories, but perhaps only because He is still made in our image.

The ghost of God sees the pretty mesh/web pattern of supercluster filaments as they are right now, that we can only model and will never observe in its entirety, given that we’re compelled to look back in time as well as across distances.

Fig 1: Distribution of light in the universe, as simulated by the Millennium Simulation Project

Being a pattern, this mesh simulation is human friendly especially as, at a pinch, it can be compared to the lights of cities and villages seen from a plane at night. Such a simile helps us to digest the lack of universe central belly – we’re reminded that human civilisation too has ‘centres’ but not one unrivalled ‘centre’.

The ghost imagined by God Replacement also sees and understands Cold Dark Matter (CDM) which remains a complete mystery to us, even though it probably makes up more of the mass of the universe than atoms and molecules do. We predict its presence as an explanation of why galaxies spin faster than they should, but CDM doesn’t give off radiation or interact with matter as we know it, apart from its gravitational pull. The ghost also understands “dark energy”, which is an answer to the question: why is the universe expanding at an accelerated rate? Dark matter and dark energy point to how little we know. How can we be sure of our place in the universe when we don’t even know what the universe is made of? Little knowledge leaves a lot of room for creative universe possibilities like extra-dimensions and supersymmetric strings. Are there CDM sentient beings sitting beside me right now on CDM chairs wondering about ‘baryonic material’ – the atoms and particles making up everything that we humans currently know about?

In God Replacement mode, we hold the often useful assumption that there are Universal Laws which cannot be broken. It is assumed the universe (unlike ourselves) is rational. God Replacement includes the search for the awesomely-named Grand Universal Theory (or GUT), which is to tie explanations of three of the four known forces together, and also the search for the Theory of Everything (or TOE) which will tie gravity to the quantum forces of the GUT. (I nominate that the theory linking the GUT to the TOE be called Gravity: the Other Universal Tool. Ie, GOUT.)

Such projects are modernist – in other words, like religions, they seek universal explanations. They’re not interested in only finding mere fragments of meaning that suit some situations and not others – which is all postmodernism expects and which is all that the unreconciled explanations of general relativity and quantum physics currently deliver (a TOE with GOUT would reconcile them). A character in Tom Stoppard’s play Arcadia declares her distaste for the afterlife: “If the answers are in the back of the book I can wait, but what a drag. Better to struggle on knowing that failure is final.” God Replacement is working out its answers as it goes along – adamant that there are definite answers and confident that failure isn’t inevitable, but insistent that no god has prepared cosmic cheat sheets.

Yet God Replacement also replaces religion’s answering of ‘why?’ with answering ‘how?’ This is more intuitively satisfying than giving up all efforts to unify explanations in the way of postmodernism, but less satisfying than religion’s answers once were. If current strong cosmological theories hold, there will never again be such satisfying answers as religion’s were in its heyday. This is due to a concept potentially as devastating as that of heliocentrism: the universe is finite. Sure, we already knew that the Sun would start its slow death in 5 billion years, first becoming a red giant and then a white dwarf, and that even before that, in about 1 billion years from now, its hot old age would make water (and therefore life) impossible on Earth. But there was always the possibility – however remote – that humanity would be able to rocketship off to another planet, or to Jupiter’s tantalisingly primordial Earth-like moon Titan, before it was Too Late. There was always the possibility that humanity – or at least, traces of its civilisation, or at least the atoms and molecules that we are made of – would last forever. But somehow, the idea that the universe will definitely cease to exist is the ultimate memento mori. It doesn’t matter what your theory of choice is. Perhaps you’re partial to the “Big Rip” – dark energy expanding the universe’s emptiness to the point where solid objects get torn apart from within and even atoms and particles are “ripped into nothingness”. Or maybe you prefer the less likely “Big Crunch” – where the collective gravity of all the matter in the universe acts as a brake on space expansion and reverses it until the universe is fitted into a space the size of a pin. In all cases, the universe will still cease to be.

Somehow, wanting to be big and important in a finite universe makes less sense than wanting the same in an infinite universe. Who cares how powerful you are, if ultimately it’ll all disappear anyway? As vast as the universe is and as old as it will be, space-time is not big enough to give us what we want: immortal influence. We need a “singularity” – an infinity – for that. Ironically, religion offered infinite time yoked with a very small universe. We now have large amounts of time and space – but no infinite. Just as Christianity preached that humanity could never reach the perfection of God without God’s help, so too can humanity never reach a temporal infinity without such an infinity already existing. And it no longer does.

Where God Replacement looks for objective universals – even though they’re no longer infinite – the Alternative God search for meaning is less ambitious. It expands into outer space those Earth-bound projects which already supply us with subjective life-meaning. We’re social animals and we find meaning in being with our friends and whanau, for example; it’s perhaps not surprising we like the idea of meeting other life forms. In spite of the distopias envisioned in films like Alien and District 9 (the aliens pick on us or we pick on them), biologist Richard Dawkins is not alone when he calls the idea of cosmic isolation a ‘sad thought’. Without proof that we are not the centre of the universe, the current US$500 billion Kepler mission looking for Earth-like planets would not be deemed necessary; we would still be held in God’s cradle and he would give us all the judgment and companionship we needed. Aliens may not be God, but they will at least be outside observers, hopefully equipped with a gift for languages and the cosmic progress-measuring yardstick we seem to crave. Maybe they could explain a few things about life, the universe and all that as well.

As long as humanity lives long enough, we’re bound to find other planets like ours, even if Kepler doesn’t find any contestants in the next three years for the Earth lookalike competition we’re running. Such failure is unlikely – if only one in every hundred stars hosts an earth, the Milky Way alone will hold a million of them, and Kepler’s target 100,000 stars will harbour hundreds. But it’s a stretch to jump from other earths to life to sentience. Some scientists believe larger planets orbiting slow-burning orange dwarf stars may actually be a better bet, as their ability to support life would last longer than that of suns like ours; even large “exoplanets” with strange or even no stellar orbits have been suggested as an outside shot.

What is life anyway? Could stars be considered “alive” as they are “born”, they grow, “die”, and “reproduce”? Certainly, charged interstellar dust has been described as exhibiting “life-like behaviours” such as self replication. Although searching for water is the logical place to start as life without water has yet to be proven, I think “carbon chauvinism” – the assertion that any and all life we find will be based on carbon compounds like life on Earth – shows very little imagination (figure 2 shows cartoonist Randall Munroe has similar ideas). It perplexes me that we can come up with intriguing theories about ten-dimensional space and squarks and sneutrinos, and yet still hold fast to the idea that life has to be solid matter. Could waves of energy produce life? Humans, who shed perhaps all their cells during their lifetimes apart from some in the brain, could be considered essentially waves of energy. And what about my imagined CDM companions?

Fig 2: Randall Munroe cartoon (xkcd.com)

Personally, I face our supposed “insignificance” in a finite universe with a self-contradictory mix of God Replacement and Alternative God strategies. For a start, it’s freeing – if the universe doesn’t care what I do, then I can do whatever I care about. Here on Earth, my place is at the centre of my own personal universe, like your place is at the centre of yours. I am important to me, and I am pleased to say I’m the right person to be making such a judgement as I am the most important person in my universe. Whoops, was that a circular argument? I own it, because it’s still more logical than trying to prove my importance to a slab of concrete or a vacuum or a non-sentient universe.

Also, because the universe doesn’t come with a ‘this way up’ sticker and all is relative, I can say that actually, from my point of view, the “actual” universe does revolve around me. The Sun and therefore the Milky Way and the Local Cluster make one circuit around me every 24 hours. Redshift – causing most galaxies to wink red tail lights as space expansion carries them off – shows they’re all spinning away from me. Sure, any other point in the universe could also be the point of revolution and the point of redshift rejection, but I’m happy to share the limelight with those points. It’s not that I’ve become insignificant again, it’s that I’ve raised the rest of the universe onto my pedestal.

But sometimes I want objectivity and some sort of outside authority saying we’re different, we’re special. Then I imagine that cosmic importance is not about who sees us but what we see. It is possible to imagine a universe with no sentient beings in it, that evolves entirely unobserved, perhaps forever. This is not the case in our universe; to all intents and purposes, we are the universe observing itself, we are the stars watching themselves. Whether our explanations of what we see are correct or not (and clearly, in the past, they were often entirely mistaken), that sounds like it could be meaningful, even if the feedback loop isn’t closed and we don’t know who to share our discoveries with (yet). The results of quantum experiments, which seem to change with observation, even tempt us to think our consciousness has influence over quantum ‘reality’. The ‘weak’ anthropic principle notes we could not have formed in a universe younger than about 10 billion years old, as the stars had not fused together enough heavy elements to create us before then. This does not mean the universe was created for us, but poetically and anthropomorphically speaking, it may have formed us for its use, as a few of possibly trillions of eyes. Star-gazing then, is not so much a hobby as a universal duty. I’ll raise my eyes to the heavens with pleasure.

Bibliography

• Brandt, John C and Carolyn Collins Petersen, Visions of the Cosmos (Cambridge University Press, 2003)
• Coles, Peter, Cosmology: A Very Short Introduction (Oxford University Press, 2001)
• Dawkins, Richard, “Queerer than we can suppose: the strangeness of science”, TED talk (http://www.ted.com, 2005)
• Gribbin, John, Galaxies: A Very Short Introduction (Oxford University Press, 1998)
• Lichtenberg, Don Bernett, The Universe and the Atom (World Scientific, 2007)
• Millennium Simulation Project http://www.mpa-garching.mpg.de/galform/virgo/millennium/
• Munroe, Randall, xkcd cartoons, http://www.xkcd.com
• Sagan, Carl, Cosmos: A Personal Voyage television series (PBS, 1980)
• Solmaz, Arif, Cosmic Diary blog, Cosmicdiary.org
• Stanford Encyclopaedia of Philosophy, http://plato.stanford.edu
• Stoppard, Tom, Arcadia (Samuel French, 1993)
• Universe Today, http://www.universetoday.com

Footnotes

1. “Copernicus probably adopted the heliocentric theory sometime between 1508 and 1514.” Stanford Encyclopaedia of Philosophy (http://plato.stanford.edu/entries/copernicus/). Galileo is often credited as the first person to use a telescope, but he actually used a description of one already invented to build his own. Digges is the first known person to have invented the telescope sometime in the 1550s (Gribbin, 2008).