13.00, Saturday 13 Sep 2008


When I was young my family included Indigo, a golden retriever with his own towel and a wide smile. I would sit and watch him as he lay sprawled with his chin on one leg, staring into the middle distance. Suddenly he would leap to his feet and trot, tail wagging, a few paces before hurling himself at the carpet, twisting as he did so to roll and throw himself around and generally have a good old time right there in the hall. What was it Indigo, hey? What did you see, did you see a ghost who said -Come play? Why that moment, hey boy? Just as quickly he would stand and shake himself down, and come back to his spot near the kitchen where I could see him and he could see me, and I'd be laughing. Where did it come from, that abrupt desire for play? How come that exact second for decanting some of the internal flywheel into rolling about with his belly in the air and legs waving? It reassured me that I couldn't see any cause, that it was something inside. It meant Indigo had his own internal life, and so I could love him more.

Newly single I sit at the table in my flat, shuffling papers, wondering how I'll know what to do next, and wishing I could be like Indigo. I drink water because I'm thirsty; I pack because tomorrow I fly to Oslo.

I was 10 years, 9 months, 3 weeks and 3 days old the day they activated the Large Hadron Collider. I was at college in a lecture the day I found out they'd found the Higgs boson, which gives particles mass. Mass gives momentum, and momentum is what keeps you moving. The Higgs is where it comes from:

the universe is a house, and you're a particle - let's say a proton - and the house is packed full of ghosts, from wall to wall like a carpet, and from foundations to rafters like roaches. You're dancing in the ballroom - there's a ballroom in this house - and as you dance the ghosts tap at your arm and tug at your collar and rest their hands on your shoulder. You turn for a second to see who it is, but the face of the ghost is hard to make out, and besides the ghosts are restless so it has already mixed back into the crowd, and perhaps there aren't any ghosts anyway - you've had a few glasses of wine after all, maybe you're imagining things - but that aside, it means that your otherwise smooth dance is slowed and shaped by the constant contact of a million touches.

The ghosts are Higgs bosons, which fill the universe so they slosh over the sides, and the contact they have with particles - like you and me - as they pass by is what we see as mass.

The lecture that day was one on particle physics, and Dr L-- came into the hall with a grin and bright eyes.

-Gentlemen! he said. He always called us gentlemen, whatever the mix.

-Gentlemen, your notes are out of date! My colleagues at Cern let me know this morning. On slide, uh, 20 from last week, where we declared the existence of the Higgs boson was unknown, well that's no longer the case. We have it.

It shouldn't have hit me so hard. We assumed the existence of the Higgs, or something like it, in most of our mathematical models. But to have it confirmed! It didn't need to have come out this way: there could have been a field that created mass, like an electromagnetic field, covering the universe. Or each particle could carry within itself mass, just like charge or spin.

But to have it confirmed... it wasn't right that mass was an external quality, I was thinking, it belonged inside. I felt violated, like someone had knocked me to the ground and emptied my pockets. I walked up the Banbury Road with my head in turmoil, each iron bar on each iron fence looked empty to me, each paving slab on the ground looked hollow, and I eyed the so-called empty air with suspicion for hoarding mass to itself, for withholding the Higgs from me.

It's funny how these things hit you.

The way you show the existence of just one of these ghosts is you stop dancing and you barrel across the dance floor as hard as you can, shouting and roaring, barging ghosts and dancers alike hither and thither, scattering them and knocking them flying. If you get it just right, you splash a clearing in the ghosts, and if you're luckier still there's a moment before they get to their feet where you can grab one, sit on his chest and hold him down by his neck and grab his chin so you can wrench his dirty face round to look straight at yours and lean in real, real close and, panting, whisper straight at him through your gritted teeth: you little fucker: gotcha.

Post-doc I studied the origins of volition.

It's not enough to know that Higgs makes things slow down. What makes 'em move to begin with? Okay, so this proton dances with that proton and that's why that one moves... but why was the one before that moving? And the one before that? And the one before that?

-You're obsessed with work, you said, the day my paper outlining the experimental procedure for isolating volition was published. -Why do we never do anything? (That was the first time. I was at my computer, watching comments and cross-linkings appear on arXiv as my ideas rippled across the community. Physics changes fast when it wants to.)

With hindsight I see you were right. I didn't know how to do anything but work, anything but respond to comments and questions. But it was also unfair: we were as active as any other couple, popular round the faculty and taking full enjoyment from the art and music that sticks to any town with a population of students. We scoured the event sheets for unusual plays and exhibitions in new gallery spaces.

Maybe that slipped. The questions to field more than filled the day, as the detector moved closer and closer to coming online.

The ghosts that fill my head can be scattered and isolated, briefly and with much effort, and I can hold one down and recognise his face: my father, say. My very own Higgs; these are the things that join me to the world.

Volition strings, if they exist, are the faintest of the faint to see. We have to look for the ragged ends of the superstrings that comprise the real substance of the universe. Most strings exist in knotted loops, which are particles. Some strings, after the Big Bang, had their loops severed and the ends of these thrash around like the end of a hose with the water turned full on. They whip, their ends moving at light speed and their middles faster still, although it's impossible to ever detect those except indirectly.

The open ends of volition strings, when they touch a particle - which is rare and fleeting - impart it some unpredictable shove. They push it into a new orbit. And so: movement.

Seeing this in action is what the detector is for. The detector is lined up such that the cut-off end of the volition string will pass through the distant star σ Octantis, which is dense and should slow it just a little, and then through the Earth, which should slow it just a little more and focus it, and then we have our detector placed flat, facing down, in the Arctic Circle of Norway looking through the rock and the mantle and through the core, and we use the entire planet as a kind of lens, and we look close, and we hope we see a twitch in the fabric of the cosmos. Volition.

-You're inert, you said, there's been a year of trying, and we agreed it was best if we parted, and as to whether this decision was right - it has to be said - I numbly say it was. That was three months back.

But you're going to be there in Tromsø, in the calibration and operations team, as the detector is activated, and in three days we'll see one another again.

I'm here because I first suggested a form of this experiment in a paper years ago, a kind of honoured guest except that the details have been refined and revised by hundreds of physicists and mathematicians since. We crowd round the screens, and although really there's no need for personal presence these days, it's a happy moment to be in, with my fellow hunters. I think of Indigo and my father and Dr L-- and you and I see my life as a careering country dance, passed from one hand to another, swung from person to person, kept moving in do-ci-dos up and down and round and round. Somehow I'm standing behind you and, as the lens cap comes off - the culmination of my work - I find myself unable to think of anything so much as the nape of your neck just ahead of me, and it would be the work of a second to rest two fingertips gently on its soft concave curve; and I fancy that the end of a volition string passes right through me, skewers me from my head through my soul itself, or maybe volition is inside me all along and I just need to grasp it, to fan its spark to life, and I understand that what I'm facing now is a decision: to connect or to not connect, that there is no default choice, there is no momentum or inertia or carrying on as you were before; that every millisecond is a choice, an opinion, an act, and it can't be avoided because volition fills us, floods us, drowns the ghosts: and I look at your neck, and my hand, and I have a choice to make.

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