In this extract from the new book Thought X: Fictions and Hypotheticals, Sarah Schofield brings the puzzling thought experiment Laplace's Demon to life.
Science is chock-full of puzzling thought experiments, from Schrödinger's cat (is it alive, dead, or just having a nap?) to the grandfather paradox (a favourite of every budding time traveller).
Thought X: Fictions and Hypotheticals collects together 14 short stories inspired by these hypothetical experiments, each one paired with an afterword from a leading scientist. Below is one of the stories, The Tiniest Atom by Sarah Schofield, which explores the idea of scientific determinism, also known as Laplace’s Demon. The afterword is providedbyDr Rob Appleby, a physicist at the University of Manchester and the Cockcroft Institute.
The boy who answers the door looks so much like Ted, all Frank can do for a moment is stare at him. Frank knows that the boy is called Thomas and that he is aged seven. Tall for his age, Thomas stares back eye-to-eye with Frank.
Frank pulls himself up. ‘Is your Ma in?’
A wren-featured woman comes to the door. Nancy. Her mouth twists down at the corners and beneath her eyes are lavender blue crescents. ‘Yes?’
Frank looks up at her. He presses his hands into his pockets and fingers the notebook segments. ‘I’m here for Ted.’
Nancy’s mouth draws tight. Finally she says, ‘You’d best come in, then.’
He drops his haversack by the door and stoops to unlace his boots. He places them between a pair of child’s shoes and a large pair of slippers, their desiccated soles slowly contracting.
Nancy is in the kitchen, holding the kettle. ‘You served with him, in Arras?’
He clears his throat. ‘Aye.’
‘Right,’ she says. ‘Right.’ She turns to the range. ‘You’ll have tea. You’ve probably come a long way. I didn’t catch your name.’
Thomas scowls at him around the door. Frank winks back.
‘Why are you so small?’ Thomas says.
Nancy twists round, wiping her face on her apron. ‘Thomas Edward!’
The boy lowers his head, watching Frank through his lashes.
‘Could wrestle any man down,’ Frank says. ‘Your dad included.’
‘No you couldn’t,’ he mutters.
‘Get out and play, Thomas.’ Nancy’s voice is brittle. Thomas glowers at Frank as he passes.
‘Aye. It’s fine.’
I drop a sandbag in place on the fire-step and climb onto it. You stoop beside me.
‘Bantam division?’ you ask.
‘They said you were coming.’ You move over slightly. ‘I’m Ted. I’m knackered.’ You point your bayonet. ‘Over there. Watch it.’
Artillery fire arches across the metallic sky, we buckle our heads down simultaneously.
You step down and fold yourself into a dugout a few yards down the trench and place your helmet into your lap.
I wince each time the rifles bark, but you just pull your balaclava closer around your face. You unravel your puttees, slide off your boots and pull a pair of socks from your top pocket. I press myself into the side of the trench. My gun is sticky with cold. I swallow back a wad of gritty spit. Along the fire-step, men merge into the brown sludge. We’re all the same – stinking, dirty, wide eyed. There’s only a handful from my battalion who made it here. Short and tough like me. We’ve got used to the banter and neck ache. We find ways to tuck in the spare fabric of our uniforms.
The night is quiet; time dragging in anticipation. A terrier trots through the trench mud and you swat it away. I watch you rewinding your puttees, your feet pigeon-toed together. You tie a precise hitch in the tapes. You take out a notebook and pencil stub. You glance up at the night sky.
Frank reaches into his pocket. He lays the notebook segments across the table. Tide-marked and speckled, they hold the contours of Ted’s body where he had kept them pressed between his tunic and vest. Frank flips one that is smudged iron brown across the page, holds it flat against the table. It springs proud when he raises his hand. Nancy’s knuckles are white on the back of the chair. She turns suddenly and leaves the room.
The water rolls to a boil, spitting onto the range top. Frank lifts the kettle off the heat and fills the teapot. He is pouring the milk when she reappears. She has a needle pursed in her lips and she sits and unspools a length of thread, snapping it with her teeth. She slides one section of the notebook towards her, resting her hands over it. Then she takes a second segment and squares them together. She threads the needle and pushes it through the paper, the thread hisses tight through the spines, drawing the sections back together. Frank watches her then he scrapes back the chair opposite.
‘You were good friends with Ted?’
He stares out of the window. ‘Aye.’
He pours the tea. Then he gathers the remaining notebook sections and orders them carefully. He hands them to her one by one. The stitched together pages twist away from each other, like an over-ripe flower.
She lays the stitched up book on the mantelpiece and places the flat iron on top of it. Finished, it is a couple of inches thick. Beside it Frank notices the empty red leather cover.
‘You’ll stay for supper, before you go on your way.’ She sets the table. Thomas comes in and washes his hands at the sink.
‘My mother’s coming.’ Nancy lifts a china dish from the dresser and spoons dripping into it. She raises an eyebrow at Frank.
He opens his mouth, then draws a chair over to the mirror hung above the fireplace, kneeling up on it to palm his hair flat. A sour-faced woman appears in the mirror’s reflection; she stands at the front door.
‘Thomas Edward.’ The woman’s voice is like a siren. ‘I hope you’ve washed your hands.’
She looks at Nancy but waves a finger at Frank. ‘Who’s this?’
‘Served with Ted. He brought us some of his things…’
‘Does he have a name?’
Frank wipes his mouth on his sleeve. He steps off the chair. ‘My name’s…’ He falters. ‘They call me Ted.’
Her eyes dart from Nancy to Frank. ‘Strange coincidence, isn’t it?’
Nancy ducks her head, scrapes the spoon against the side of the serving dish. She turns to the boy, sitting watchfully. ‘Thomas, have you washed your hands?’
Later, the older woman looks on as Frank thanks Nancy for her hospitality and Nancy thanks him for visiting. Frank stands alone in the lane outside the house. He waits for the light in the kitchen to go out then he hops back over the wall and picks his way into Ted’s kitchen garden. He unrolls the blanket from his haversack and lays it onto the warm soil between the potato drills. The speckled night stretches overhead. Orion’s belt. The Plough. He knows about them now. He looks at them with narrowed assessing eyes as Ted had. He squeezes his arm, feels the shrapnel shifting beneath the skin.
I wedge myself beside you into the cubbyhole. ‘Room for a small one.’
‘Not really.’ Your elbow jabs in my side. You bend double while I lay back on my arms in your shadow.
‘We look a pair,’ you say.
I pull a hard square of fruitcake from my pocket. Break it in two. You raise an eyebrow at me. ‘Found it…’ I grin at you.
You push your notebook inside your tunic. ‘Ta.’
We rest there together, the night turning. Waiting in the silence.
‘I’m okay,’ you whisper, ‘I’m okay as long as I can see the stars… Make notes…’ you pat your chest. ‘Keeps me busy,’ you say. ‘Keeps me warm.’
We exchange glances as three shells explode one after the other not far to our left. We huddle back against spraying earth. A cry comes from somewhere down the trench. ‘Stretcher bearers, this way!’ Staccato shots fire.
A shell lands a few feet shy of the trench. It shakes the earth, rattling my teeth, dissolving my insides. My ears sing.
Tight jawed, hard faced, you push yourself out of our dugout. I climb up onto the sandbag on the fire-step. We stand shoulder to shoulder as the shells rip over us.
Frank lurches awake, his throat raw, the taste of blood in his mouth. He holds his breath to listen. A breeze hushes across the garden. A light flickers on in the kitchen window. He sees Nancy’s pale face squinting out into the dark.
You have your notebooks – you draw and make notes. You show me them, how they are sections of the same book, the binding threads unpicked so that you can distribute the book’s bulk under your uniform. ‘My Nancy did it, so I could bring it.’ You tell me about the lectures you go to in London; philosophy, physics, astronomy, the natural world, when you can afford it, when Nancy will let you, when you earn enough from your carpentry. You show me the diagrams in your notebook. As we share a smoke, you tell me you heard about my gallantry award. I blunder over it and change the subject. But you look at me with eyes of an equal. They start calling us little and large.
He wakes in daylight and birdsong. He stuffs the blanket into his haversack.
When he turns, Nancy is standing in the garden. ‘You’re still here, then.’ Her eyes are hooded. She bends to pull a beetroot. It tears from the ground in her tight wrought fist, earth scatters across the vegetables.
Frank gazes at the small crater the beetroot has left. When he looks up, she has gone but a hoe is propped against the garden wall. The handle points in his direction.
He weeds around the cabbages, then the carrots and pea canes. He places his hands over the smooth intimate places where Ted’s hands have been on the ash handle, and hoes in unwieldy strikes. He feels the fragments grating inside his arm. He leans on the wall as Nancy hangs sheets over the washing line. Thomas circles her with a toy plane. Like a moon, he thinks.
‘What are you smiling at?’ she asks.
Later, he sits at Ted’s table for lunch. Thomas props his chin up reading the morning paper, his plate pushed to one side.
‘Reads it every day,’ Nancy whispers. ‘In case there’s any news. In case our telegram was wrong…’ She looks at Frank.
Frank reaches over and presses the paper shut, points at the headline. ‘You see some sights out there. A shell tears up metal like paper.’
Thomas listens, his mouth open.
‘Exploded earth moves like water. Your dad… if it were quiet, he’d go and look at things, up close, see how they’d misshapen.’
‘Obsessive,’ Nancy nods. ‘Always...’ Her eyes widen. ‘You know. How things are put together.’
Frank picks up his china cup and turns it in his hands.
‘Did he tell you about us?’ Thomas says.
He puts the cup down and looks at his plate. The beetroot seeps crimson into the wedge of bread. ‘Aye.’ He scratches at his bare scarred forearm. ‘Aye, he did.’
Frank lays his arm on the table. ‘Bits of all sorts in there. Metal, wood… Feel. Go on.’
The boy reaches out hesitantly and touches Frank’s skin. He retracts his hand and slides it under the table.
Nancy gets up and takes baked apples from the range.
‘I was thinking of staying, just a while,’ says Frank. ‘For Ted…’
Nancy puts the baked apples on the table. She scoops the largest out and puts it into his bowl. The fruit is tangy and sweet. Thomas pushes the apple flesh around his bowl until it browns.
Frank goes into Ted’s workshop and breathes the cool dusty air. He touches the workbench, the machinery, saws, measuring tools, neatly labeled slabs of rosewood, oak and pear. He flips a crate, stands on it and leans on the bench top.
He takes a chisel from its setting, turns the blade between his fingers. He finds Ted’s whetstone and oil and blows the dust off them. He sits on the bench with the whetstone between his knees and runs oil onto it. He circles the blade against it until the metal is silvery keen. It nicks a notch of skin when he tests it on his thumb pad.
Nancy and her mother are talking in the garden outside.
Nancy says something that Frank doesn’t catch.
‘Well, where’s he sleeping?’
‘He’s renting a room, Ma. In the village.’
‘I don’t think so, my lady. I’ve asked round…’
‘What’s stopping him getting back to the front?’
‘His arm. He’s…’
‘You can’t keep him like a pet. Has he no family to go to?’ She sighs. ‘You need to get rid. Someone’ll be missing him.’
Later. The light is fading. Frank has sharpened all the tools and is oiling the pruning shears. Nancy leans in the doorway. ‘Supper,’ she says, sweeping her hair back. ‘We’re going to church in the morning. Will you come?’
Frank sits between Nancy and her mother in a pew close to the front. People bow forward as if in prayer and stare at him as the organ plays.
The vicar climbs the pulpit. Nancy’s mother leans in. ‘Mr James is a close friend of this family,’ she hisses.
Thomas catches a yawn in his fist.
‘The lesson is taken from the thirteenth chapter of First Corinthians, beginning at the first verse.’ Mr James clears his throat. ‘“Though I speak with the tongues of men and of angels, and have not charity, I am become as sounding brass, or a tinkling cymbal.”’
You beckon me into our dugout. Point into the corner at a small burner. ‘Made us this, from scraps lying about. It’ll disperse its smoke. Just need some fuel…’ you raise an eyebrow at me. It doesn’t take me long to acquire some.
You light the little flame and we set a pan of water over it. We sit and watch it. Then you flip through one of your notebooks. You hand it over.
‘I designed this. Already started it at home…’
I look at the drawing. ‘A clock?’
‘It’s called an Orrery. Miniature mechanical solar system. I worked out a sort of scale for it. Got to be right, see.’ You tap the page. ‘The scale isn’t consistent, or the thing would have to be huge for it all to fit. I’ve altered it to make the planets understandable.’
‘Nancy calls this sort of thing my hobby. I’ll probably get home to find she’s sold my tools and turned my workshop into a home for stray animals.’ You give a dry laugh. The stove flame flickers violently. ‘I’m going to make a discovery.’ You speak so quietly that at first I don’t follow you.
You look at me steadily. ‘It’s a ripe old time for it; new things being discovered. Shame the war’s thrown it all off kilter.’
You take out your pencil stub, whittle the tip, blow the shavings into the flame. ‘You heard of Laplace’s demon?’
‘Religious thing, is it?’
You shake your head, smiling. My cheeks burn.
‘Laplace. A scientist, philosopher. He has this theory. The theory’s the demon,’ you look up darkly, ‘because it’s a frightening idea.’
You don’t say anything for a moment, but stare into the flame. ‘All the stars and planets, all their movements are determined. You could wind time back and forward, and if you know the speed, forces and positions of them, in the past, and now, you can work out what they’ll do in the future. At any time. It runs like a clock.’ You pat your chest, where your notebook is. ‘Laplace said if the stars and planets work so precisely, then everything else must, too. Every tiny atom. Every being. If you could invent, or find an intellect, that could see all of the past and present, know all the forces and whatnot that will affect it, the intellect would be able to tell our futures. It stands to reason…’ you say. ‘The regularity astronomy shows us in the comets and what-have-you “doubtless exists in all phenomena”… nothing’s uncertain.’
I lift the boiling pan off the stove. ‘Not a big one for books. Rather be doing…’
You hold the mugs steady. ‘Don’t you think that’s a frightening thought? Years ago, they thought the planets’ and stars’ movements reflected the anger of the gods. But clever men had the presence to record celestial happenings, began to find patterns. Laplace says it’s the same with everything else. We just haven’t found a way, a formula, to calculate all the movements and forces that affect us.’ You drop your voice. ‘Even though the great intellect that would have to calculate it hasn’t been discovered yet, everything is already decided. We don’t know how to know them yet, but all our decisions are already made, decided for us.’
‘One day…’ you swill the tea in the cups. ‘Men will look back and see how stupid we were for thinking we could decide our own fate.’
‘“… I understood as a child, I thought as a child,”’ The vicar drones. ‘“But when I became a man I put away childish things. For now we see through a glass, darkly… now I know in part; but then shall I know even as I am known…”’
‘Will that be what you discover? This Laplace thing?’
You shrug. ‘Perhaps… how it works. I’ve a thought it’s to do with the universe being like a huge machine, able to hold all that information. There must be a way to understand it, see what’s predicted. It’s a bugger being here. But I will discover something, maybe the formula, how to read it, when this is all over. I have this feeling. I’m going to make it through. You too, pal.’
I see your toes have slid in on themselves.
‘After… you’ll come and visit us: me, Nancy and Thomas. I’ll have made my discovery and we’ll sit at my table, chatting about old times while Nan makes supper. Maybe we’ll tell them a few tales about now. The good times…’ you pause. ‘Anyway, we’ll all tick along together just right. I know it, pal. We’ll be two old fellas with grown sons of our own one day and they’ll look just like we do now.’
‘Here endeth the lesson.’
Nancy’s mother glares at Frank as he rubs his eyes.
‘So in conclusion friends… Our men, out there, they know not their fate. We cannot know our own. The day, the hour. So make good your thoughts and hearts. And trust that all things are held in the hands of God. Now may we all join in this wondrous hymn to nature, All Creatures of Our God and King.’
As Frank leaves, Mr James shakes his hand.
Nancy steps forward. ‘This is a friend. Friend of Ted’s.’
‘I see. You served with Ted. We all…’ He looks hollowed out. ‘You’ll be called back soon, no doubt.’
Nancy’s mother bundles Nancy and Thomas out into the sunshine, giving the vicar a look.
‘Took some shrapnel…’ says Frank.
‘It’ll work its way out. No need to sit round waiting… And you must have family of your own… who’ll want to see you.’ He catches hold of Frank’s arm and draws him to one side. ‘You know, Nancy hasn’t been well. Since…’ he pauses.
Frank looks out to the brightness beyond the church porch where Nancy stares into a holly tree. Her mother is fussing with the boy’s shirt.
‘Perhaps it’s time to go… let the mourners mourn.’
Sunday afternoon passes slow and warm. Frank goes to Ted’s bookcase and runs his hands along the finely bound books. The spines glow, the leather is recently polished but when he pulls one out it sticks as if it has not been moved in some time. Frank cracks the spine and flips through the pages. The words scuttle about. He sits down, rubs his face. He squints at a diagram where the labels lean forward like fervent little ants. He rests his head against the back of the chair.
You change as soon as we enter the Arras tunnels; shrink into yourself. You’ve been quiet all day, taken on a queer colour. ‘Safe down here,’ I say. ‘At least compared with up there. Like home for me. Dug enough of it…’
You don’t reply as you stride on, ducking your head away from the chalk seams and echoes. I dodge along the yellow-lit tunnel to keep up. In our new quarters, we change into dry clothes. Make our bunks.
It is late. Men sleep heavy. But you’ve been shuffling and turning since we made for bed. I’m nearly asleep when I hear your voice. A gut groan, slowly getting louder.
‘Oh God, oh God.’
I turn over, squint at you. You rock like an overturned beetle, clutching your ears.
‘What’s up, pal?’ I reach over and shake you. ‘Are you feeling rum?’
Your eyes are wide. You are high and sour. It turns my insides to see you like this.
‘Try and sleep.’
Your breath drags wetly. ‘I can’t… I’ve got to get out.’
I pat your shoulder and you dart out a hand to grasp mine. You squeeze it against your chest, where your heart pounds as fast as a machine gun. And it is then I understand where your fear goes when we’re being shelled in the trenches. You simply swallow it so deep inside you that it has to emerge somewhere else.
Someone across the way sighs. ‘Put a sock in it.’
I cast around desperately. One of your notebooks is tucked into your bunk. ‘Imagine… Imagine you’re somewhere else.’ I feel you nod. ‘Think of your stars…’ I kneel beside you, ease your notebook out. Flick through the pages. Peer at your jottings.
‘The nebulous something… I can’t read your bloody writing, pal.’
You steady a little.
I skip on some pages. ‘What’s this… here we are; your mate, Laplace, Ted. “We may regard the present state of the universe as the effect of its past and the cause of its future…”’ I feel you loosening like a bolt. ‘“An intellect which at a certain moment would know all forces that set nature in motion… If it were vast enough…”’ I flip the page ‘“…it would embrace in one single formula the movements of the greatest bodies of the universe and those of the tiniest atom.”’ Your breathing slows. ‘“… Nothing would be uncertain and the future, just like the past, would be present before its eyes.”’
I wait with you, until your fingers slacken and I can slide my hand free. I lie down as quietly as I can. My heart squeezes. And I can’t sleep.
In the morning we take our mess tins to the kitchen. We pull back our shoulders and stand side by side.
Nancy leans over him. His jaw is tight. His shoulders are braced back.
‘Ted.’ She lifts the book from his hands, slides it back onto the shelf. ‘I’ll look after you…’
She leads him up the stairs. He stands meekly as she pulls his shirt over his head. She guides him to her bed, and he lies there while she pulls the sheet over him. She strokes his hair back off his forehead. It is a fresh summery afternoon and he sleeps like a child.
You cope during the day although you are surly and short tempered. I don’t take it personal. As we go about like moles, I point out the stuff folk have carved into the chalk walls; sweethearts, dates and blue mottos.
You lose it again at night. Your spine is tight through your shirt. Huddled against the wall beside your bunk, you scrape away at it with your knife, the chalk pattering on the floor. Men are stirring.
‘Ted,’ I hiss. I tap you on the shoulder. ‘Ted, stop.’ But you won’t stop. I shake you. You’re solid, like a piece of stuck ore. I grab at your hands. Your knife slices my palm and I snatch it back.
‘Stop, pal,’ I say. ‘Look what you done.’ I push my bloody palm in your face. You drop the knife onto your bunk, look at me starkly. ‘I’m sorry. I’m sorry.’ You hold my stinging hand. You pull me into you. You hold me so tightly I can’t pull away without risking waking the others. Through a gap under your arm I can see what you’ve done to the chalk wall. I don’t understand it, some sort of maths; a triangle, a squiggle, equals, a nought. An equation. Over and over so they all merge together.
Nancy rocks him against her. Outside the moon is large and confused. He sits up and looks at his split, bloody fingernails.
She is looking at the headboard. ‘See what you’ve done,’ Nancy chides.
Frank does not understand the markings he has scratched there, but this he understands well enough: an equation, a mysterious short hand, which means this thing, plus that thing equals the next. It is fixed and certain. There is no choice. It is already decided. Fate. Unstoppable like a stream, dammed by a child, the water has to find another way. Even when it is bombed and broken, it must add up. He must make it add up. ‘It should have been me. I should be dead. Ted had something to discover. I’m fixing it.’
Nancy steers him down the stairs and out into the garden. ‘You can’t sleep in here. You have to go; it’s night time.’ He stands amidst the vegetables and watches her go back into the house.
The call echoes down the tunnels. You help me gather my pack, your nimble ease returned. Your own pack is slung ready on your back.
While my guts squeeze and turn, you look like your old self again. You jostle ahead along the corridors following the arrows to the No. 10 Exit. I trail behind. The biting chill comes first. Then a growing dawn light. You are smiling as we climb the rough cut steps, blink away the freezing sleet. We emerge like ants from a crack in the dirt. I shiver. You pull me up. You look at me. You are you again, and I am me. And we charge. Machine guns rattling. Shells arcing over us. I lift my arm, shield my face from flying debris. You drag me in your wake. You are before me, and I am your shadow. We run. Stumbling over chopped up earth.
You stop so suddenly I slam into you. You spread yourself. And keep spreading. And you are falling backwards. ‘Ted, pal…’ I shout. But you don’t turn, you just keep falling and I try to hold you, but I am underneath you. Pinned and breathing in mud. I wriggle, try to lift you off me. I see that you are now not one, but a million pieces. And you are everywhere, splintered across the field. Splintered into me.
He spends the next day in the sun. He has found a garden sieve. He sits in the vegetable patch sifting soil through it. Each fine grain, as it falls, must fall where it falls. Because this is already decided. Already known. He thinks and thinks about how he might make Ted’s discovery; the formula in the universe machine. The day passes. After supper, Frank sits with Nancy by the range. Thomas leans over a jigsaw puzzle at the table.
‘What are you doing that now for?’ Nancy closes her eyes. ‘Bedtime soon.’
He bristles, slides the wooden puzzle pieces around.
Frank goes over to the table. ‘You should start with the corners…’
Thomas hunches his shoulders. He pieces together some yellow bits of puzzle. The sun. He groups other similarly coloured pieces. Planets, Frank sees, picking up a piece and inspecting it. The paste holding the picture to the board is flaking. Thomas puts out his hand and glowers at Frank.
After Nancy has sent Thomas to bed, Frank returns to the puzzle. Most of it is completed. The star clouds, the red, blue and green planets. He clips an edge piece into position. Nancy comes over and joins him. She leans across him and slots a piece into place. Her hair brushes his cheek.
‘Looks like his father, don’t you think?’
Frank reaches for another piece of puzzle.
‘It gets to me, that. Sometimes.’ She picks up a piece then puts it down again. ‘So I think of him as a little companion instead. Like a puppy or something.’
‘We had a terrier in the trenches.’ Frank says. ‘A ratter.’
‘Ah. Ted wouldn’t have liked that.’ She smiles. ‘When I was a girl, on holiday one year, there was this old dog that followed me around. At night when everyone had gone to sleep I went out to find him. He slept over my feet. He never barked or anything.’
Frank turns a puzzle piece in his fingers.
She looks up. ‘The day we left my mother chased it away, clapping at it down the street. Cowering, it was. Looking at me... She said I’d done enough damage.’
Frank slots the bit into place.
‘I’ll be going to bed, then.’
He looks at her. Then he nods, goes to the door and pulls on his old worn boots. ‘Night, then,’ he says.
She turns off the lamp. ‘Night.’ She is a silhouette. Her hair a static halo around her head, she tilts her face. He steps towards her. She doesn’t move, but he can see she is trembling. He reaches out. She is soft, complete.
‘Ted,’ she moans into the top of his head.
Her breath is hot and cold on his skin. Her fingers are on his nape, tingling over his scalp. He shudders as she touches the memory of tin hat bruises. Soft skin over hard bone. Deliciously ghastly. Balmy. Woozy. She is kissing him and her teeth press against his and he kisses her back.
‘Ted,’ she says. ‘Ted.’
He jolts her onto the table, rolling onto his toecaps, scattering pieces of the puzzle. He forces his fingers between her clothes, seeking skin, she eases his hands out, guides him up her thigh. Jigsaw pieces fall, bouncing onto the floor. She grabs at his shirt, her fingers urgent on his buttons. He strains his body against her; some clockwork desire. An elusive urge. The harder he pushes towards it, the further away it moves. She is panting like she’s hurt. I am pushing and pushing and you, Ted, are bloodied and pulped. Your stuffing punched out, palm open like a question. Your face isn’t where it should be. And if you hadn’t fallen exactly where you did, it would have been me, pal. It would have been me…
The night draught chills his damp skin. A bubble of pain strains in his chest. He sobs. They hold each other until there is silence. She lets go and looks away. She slides off the table and shakes puzzle pieces out of her skirt and she fastens her blouse. Frank buttons up and shuffles his boots. A jigsaw piece skitters across the floorboards. He bends and picks it up. He collects the bits under the table.
Nancy relights the lamp and scoops together the disjointed bits on the tabletop. She sweeps them into the box and replaces the lid. Her face is golden in the lamplight.
In the morning, when Frank goes to look, he discovers his old boots have gone and in the place where he’d left them is a pair of brown leather shoes; toes slightly together, a smudge of wet polish over the eyelets. He stares for a moment. Then he slides his feet into them and wriggles his toes against the newspaper padding their ends. His feet finish where Ted’s arches rose. It feels a little like he’s falling backwards. He pulls the laces tight.
He spends the day in the workshop. He searches through Ted’s boxes and he finds turned wooden spheres labelled Sun, Jupiter, Saturn and smaller ones labelled with letters. He cups the sun in his palm, and runs sandpaper over its camber. He sorts through the bits of the construction inside the box.
Later, he goes into the house and lifts the notebook down from the mantelpiece and consults Ted’s diagram of the Orrery while he leans against the range. He skips idly forward through the pages. Near the back of the book, Ted’s handwriting slopes urgently across the page, and then he has rotated the book and written more lines over his notes vertically up the page, the letters fading as the pencil tip has worn down. The words are hard to decipher. Frank holds the book one way and then the other. ‘…unsure about the paradox of the demon… readily… if an alternative theory…’
Nancy carries bed linen into the kitchen. ‘Potato pie for supper, Ted?’
He nods and flicks the pages back to the diagram. He returns to the workshop where he clips the planets and movements together, following Ted’s design. It is easy – like a puzzle that’s already been made and then broken up again.
When it is done, Frank carries the Orrery through to the kitchen, where Nancy is slicing bread. He sets it on the table beside the breadboard.
Nancy beams. ‘You finished it.’
Thomas leans on the table and spins the planets. Frowning, he watches them turn. The movement is smooth and clear. It rotates like a toy.
I’m getting on with it, Ted. I’m putting it all together.
There’s a sharp tap at the window. Nancy’s mother stands in the doorway. ‘Nan.’ Her mouth is tight and her eyes travel over every detail of the moment. ‘A word.’
Nancy hesitates, before placing down the bread knife.
Frank pushes his toes into the wadded shoe ends. The shrapnel fizzes under his skin. ‘Nan was just about to serve up supper.’ His fingers slide to the wooden handle of the knife. He turns it fractionally so that the blade points towards the doorway.
‘Well.’ Nancy’s mother glares at Frank. ‘I wouldn’t want to interrupt...’
‘Then don’t.’ Frank says. They all look surprised, Ted. They didn’t expect that. But then, that’s me; small, unpredictable.
Nancy’s mouth falls open but she doesn’t say anything. The older woman’s cheeks flame, then she yelps and turns on her heels. Nancy puts a hand to her mouth. Her eyes glitter and Frank cannot tell whether she is horrified or delighted. After a moment she hurries out of the door after her mother.
Thomas looks at Frank. There is caution, but also something twinkling and familiar. He is looking at me like you did, Ted. When you asked about my gallantry award.
Frank shrugs mildly. Then he spins the planets again. The boy watches, his brow creased. Eventually he points and says: ‘It’s too big.’ He turns his sharp eyes on Frank. ‘Mars. And Mercury. Compared with the size of Jupiter. It’s wrong. They’d be much smaller than that. So small we wouldn’t be able to see them.’ He pokes the mechanism. ‘And the planets don’t just go round in a circle like that. I’ve read about it. It’s more complicated…’
‘It’s just an idea of the real thing. So we can see it.’ He’s looking warily at me. ‘If we couldn’t see them clearly, we wouldn’t be able to understand it. How it works, how everything moves. You see…’ And, Ted, I’m explaining it to him like you did to me. And he is nodding, thoughtful, like perhaps he sees you in me. I’m here, pal. I’m here for you. And, if Thomas helps me, we’ll make your discovery, about how to use the planets, figure out the formula. Everything will continue like before. We can do it, pal. We can.
DrRob Appleby, physicist at theUniversity of Manchester and theCockcroft Institute
Laplace’s Demon is the older of the two great ‘demons’ of physics and can be traced back to an essay published by Pierre- Simon Laplace in 1814. The actual word ‘demon’ never appeared in the original work; instead Laplace talked of an ‘intellect’:
‘We may regard the present state of the universe as the effect of its past and the cause of its future. An intellect which at a certain moment would know all forces that set nature in motion, and all positions of all items of which nature is composed, if this intellect were also vast enough to submit these data to analysis, it would embrace in a single formula the movements of the greatest bodies of the universe and those of the tiniest atom; for such an intellect nothing would be uncertain and the future just like the past would be present before its eyes.’
His demon is concerned with the role of determinism, reversibility and free will in a universe obeying the laws of Classical Mechanics and the demon has, as discovered by Frank and Ted in ‘The Tiniest Atom’, some startling implications.
To understand the demon, let’s go back to the laws of Classical Mechanics. These laws of nature, as formulated by luminaries like Newton, Lagrange and Hamilton, are a set of ideas and equations that let us calculate and predict the motion of physical bodies. The simplest formulation isNewton’s, in which the push or pull of one body on another is described using the idea of a force. For example, we can apply a force to a bike to push it up a hill, or to a string with a conker attached to the other end, to keep the conker from flying off. Once we figure out the forces on a particular body, by a combination of experience and insight, Newton’s equations let us figure out the motion in the future if we know where and how fast it is going at the present time. If there is no force then the theory simply tells us the position and speed in the future by applying the equations. This is extremely powerful. For example, when combined with the theory of gravity by the same Mr Newton, we can put satellites into orbit and even send men to the moon.
The laws of Classical Mechanics have two very important features built into their structure. The first is reversibility, meaning time can run either forwards or backwards to show how the motion evolves. In some sense, the equations do not care about the direction of time and work either way. The second feature is related to the first and is called determinism. Essentially this means that knowing the position and speed of a body at some time is all we need to know to figure out exactly and uniquely its past and future motion. So if I know the position and speed applied to a rocket now, then I know its position and speed precisely for all time simply by applying the equations.
This apparently innocuous feature has a startling consequence. Imagine our universe is made of tiny particles that obey these laws of Classical Mechanics, and that the current state of the universe in its entirety is made up by their positions, and speeds at a given time. In other words the state of the universe is essentially a snapshot of all of these particles at some time. If they obey the laws of Classical Mechanics then it’s possible, knowing the current state, to calculate the state slightly in the future and slightly in the past. Hence it’s possible to figure out the positions and speeds at any time, both in the past and in the future. They can be calculated in an entirelydeterministic way. This is the essence of Laplace’s demon, which is an entity that can somehow know all of these positions and speeds and hence know (albeit through a fairly complicated calculation) the state of the universe at any time in the future. Pretty disturbing stuff, when we consider the notion of freedom for those people living in this universe and made up of these little particles! This is sometimes called the clockwork universe, comparing the universe to a mechanical clock. But where does it leave free will?
These startling conclusions on determinism and free will are the essence of Laplace’s demon. But they only apply in a universe that obeys these Classical laws. The standard way out is to appeal to quantum mechanics, where inherent indeterminacy means it is impossible to know precisely the position and speed of a particle at a given instant of time. This uncertainty is built into the theory, which our universe seems to obey, and so it is simply impossible to know the current state of the universe. More recent arguments against this demon have come in the form of information theory and the ultimate computational power of the universe, which hinge on the amount of information it has been theoretically possible to compute given the current age of the universe. Whatever the possible resolution, there are certainly enough counter-arguments to hang onto free will for the inhabitants of this universe for at least a little while longer.
Thought X: Fictions and Hypotheticals is out now (Various authors, Comma Press, £9.99)