"No, come on," she says. "Tell me about this whole God-or-the-multiverse thing."
"OK," I say, lighting my cigarette. "Sorry—do you have some sort of ashtray? I can go outside if you want..."
"No, I'll get you a saucer."
"God or the multiverse," says Adam softly as Heather gets a saucer. "Hmm."
"Are you both familiar with basic quantum physics?" I say. "Not the really hardcore stuff, but the kind of thing you'd find in a popular science book. You know, the wavefunction and probability and that sort of thing."
Adam's shaking his head. Heather cocks her head to one side as if she's trying to make the information roll down a hill in her mind and come to rest in a place she can access it.
"I should know it," she says. "I think I did know it once. But you ignore all that stuff when you're working on the molecular level. It just doesn't have any perceivable effects so it can be disregarded."
"I'm afraid I'm completely in the dark," says Adam.
"OK, well in a nutshell—and I warn you, I'm doing a humanities Ph.D. so you could probably get this from a more reliable source—quantum physics deals with subatomic particles, in other words, particles that are smaller than atoms."
Adam now frowns. "Call me nuts, but I'm having this odd sensation as if I'd seen one of these particles once or something," he says. "Maybe I'm drunk. I must have learnt this at some point and then forgotten it. Anyway, despite all that, my brain is begging me to ask you: What on earth is smaller than an atom?"
"Oh, well, everyone knows that an atom is made up of neutrons, protons, and electrons," says Heather.
"And those parts are all made up of quarks," I say. "Apart from the electron, which is indivisible—or at least people think it is. People thought the atom was indivisible a hundred years ago, and before that they didn't think it existed, so it's not as if we know everything."
It's cold with the back door open; Heather gets up and takes a small cardigan from the back of a chair and puts it on.
"I think we're pretty sure about the electron," she says. "Brrr. It's cold."
Adam and I exchange a look.
"Anyway," I say, "quantum physics deals with those tiny particles of matter. But when physicists first began theorizing about these particles and observing them in action in particle accelerators and so on, they found out that the subatomic world doesn't act the way we'd expect."
"How?" asks Adam.
"All that common sense stuff—the past happening before the future, cause and effect, Newtonian physics, and Aristotelian poetics—none of it is applicable at a subatomic level. In a deterministic universe, which is the sort Newton thought we lived in, you can always tell what's going to happen next, if you have enough information about what went before. And you can always know things for sure. It's either day or night, for example: It's never both at once. On a quantum level, things don't make sense in that way."
"This is the stuff that does my head in," says Heather.
"Yeah, it's weird," I say. "It's like ... there are particles that can go through walls just like that. There are pairs of particles that seem to be connected and stay connected in some way even when they are separated by millions of miles. Einstein called it 'spooky action at a distance' and rejected it completely, as it seemed to suggest that information could travel faster than the speed of light."
"And nothing can travel faster than the speed of light," Heather says. "I'm with Einstein on that one."
"Anyway, one of the weirdest things about subatomic particles is that something peculiar happens when you observe them. Until they are observed, they exist in a smeared-out state of all possible positions in the atom: the superposition, or the wavefunction."
Adam's shaking his head. "You've lost me, I'm afraid," he says.
"OK," I say. "Imagine that you are out on a walk and I don't know where you are. You could be at the university, in the park, in the shop, in a spaceship, on Pluto, whatever. These are all possibilities, although some are more likely than others."
"All right," says Adam.
"Well, conventional logic tells us that you are definitely in one place or another, regardless of whether or not I've seen you there, or know for sure that you are there. You are somewhere, I just don't know where that is."
Adam's nodding and, for a second, I imagine a life so normal that I could be with someone like him, perhaps sharing a house like this, and have such a mundane, but somehow amazing, thought: Is he in the shop or is he at work?
"Anyway," I say, "obviously you're standing in for the particle in this example ... Well, quantum physics says that when your situation is unknown—so you could be in the shop or in the park for all I know—you actually exist in all places at once until someone finds out for sure by observing you. So instead of one clear 'reality,' there's a smear. You're in the shop and the park and the university, and it's only when I go out looking for you and see that you're in the park that all the other possibilities melt away and reality is set."
"So observation has an effect on reality?" says Adam.
"Yes—well, in this way of looking at it. This idea that all probabilities exist as a wavefunction until an external observer looks at—and therefore collapses—the wavefunction is called the Copenhagen interpretation."
"Are there other ways?"
"Yes. There's the many-worlds interpretation. In a nutshell, while the Copenhagen interpretation suggests that all probabilities collapse into one definite reality on observation, the many-worlds interpretation suggests that all the possibilities exists at once, but that each one has its own universe to go with it. So there are, literally, many worlds, each one with a tiny difference. So in one universe you're in the park and in another you're at work and in another you're on the moon, or at the zoo or wherever."
"Those are the only two choices, right?" Heather says. "Like most people believe in one or other of those two?"
"Yeah, I think so," I say. "I think most people favor the Copenhagen interpretation, though."
"So how does this relate to the big bang?"
"Well," I say. "If you imagine the primordial particle: the thing that went 'bang' fourteen billion years ago ... That particle should be just like any other particle. It would have its own wavefunction—a series of probabilities about where it was and what it was doing. So what we know of quantum physics suggests that unless an external observer showed up and observed the exact state of the particle, its wavefunction would not collapse. In other words, it would exist in a state of all the different probabilities at once. It would be both fast and slow, moving left and right, here and over there all at once. An observer external to the universe must be God. So perhaps God collapsed the wavefunction that became the universe. In other words, out of all probabilities God collapsed the original particle into one universe, in which we now live. That's the Copenhagen interpretation applied to the original particle. If you reject that, you're left with the many-worlds interpretation, which would suggest that there is no external observer and no collapse. Instead, all the probabilities exist 'out there'—every possible universe you could think of exists alongside this one: some hot, some cold, some with people, some without, some that create their own 'baby universes' and some that don't..."
Heather groans. "I knew there was a reason I'd forgotten this stuff."
"What if you reject this quantum physics?" asks Adam.
"Then I guess your CD player and credit cards stop working."
"I don't have a CD player or a credit card."
I grin at him. "Yes, but you know what I mean. Real technology is built on quantum physics. Engineers have to learn it. I mean, it is nuts, but it works out there in the real world."
"God or the multiverse," says Heather. "Which one would you choose?"
"I'm not happy with either of them," I say. "But probably God—whatever that actually means. Call it the Thomas Hardy interpretation: I'd rather have something out there that means something than feel like I exist in a vast ocean of pure mea
ninglessness."
"What about you, Adam?"
"God," he says. "Even though I thought I'd given all that up." He smiles without showing his teeth, as if doing more with his mouth would break his face. "No, it does make sense: the idea of an external consciousness. I prefer that anyway, given this choice."
"Oh well, I'm on my own then with the multiverse," says Heather.
"You're never alone in the multiverse," I say.
"Ha ha," she says. "Seriously, I can't believe that God made life, not with the research I'm doing. I mean the evidence just isn't there. And I get so many threatening letters from creationists that I just can't align myself to them in any way."
"I don't think this means aligning yourself with creationists," I say. "Surely some external being could have sparked the very beginning of the universe and then everything else just evolved as scientists think it did."
Although as I say this I think: via Newtonian cause and effect, and I realize that this is at odds with the idea of a quantum universe, and I suddenly don't know what to say.
"What is your research exactly?" asks Adam.
"Looking for LUCA," she says. "Well, that's how the headlines put it whenever science journalists write about it. LUCA stands for Last Universal Common Ancestor. In other words, searching for the mother of us all."
"She's got this computer model," I say. "You have to see it next time you're in the office. I didn't understand it when I looked at it, but it still gave me the shivers somehow."
"The universal mother," says Adam. "Interesting."
"Don't tell me—you're thinking like the Garden of Eden, with...," she begins.
"No, no. The great mother. The beginning of everything. The Tao is called the Great Mother: Empty yet inexhaustible, it gives birth to infinite worlds. That's from the Tao Te Ching."
"Oh," says Heather. "Well, that's just as bad. Who wants pudding?"
Chapter Twelve
After pudding—baked apricots with honey, cashew nuts, and brandy—and a long conversation about LUCA, and some other entity called FLO (the first living organism), Adam and I thank Heather and leave together, trying not to slip on the frosty pavement.
After we are out of earshot of the house, Adam laughs.
"What?" I say.
"Well, I didn't like to say, but I'm not sure I care about which type of bacteria we evolved from."
"Biologists do always tend towards the most depressing explanations for things," I say. "I wasn't convinced by Heather's reaction to my idea about machine consciousness, either."
"No. She likes the status quo, I think."
"I think so, too. But I don't see what's wrong with the argument. At some point animals evolved from plants and conscious life was formed. What is consciousness? Obviously it's made from the same quarks and electrons as everything else, perhaps just arranged in a different way. But consciousness is obviously something that can evolve. Samuel Butler said as much in the nineteenth century. If human consciousness could evolve from nothing, then why can't machine consciousness do the same thing?"
There are obvious objections to this idea, some of which Heather did point out. For example: What if consciousness can only exist in organic life-forms? But what is an organic life-form? Machines can self-replicate. They're made from carbon. They need fuel, just like we do.
"Unless consciousness isn't made from matter," says Adam.
"Yeah, well that's possible, too," I say. "But I do sometimes wonder: If a computer read every book in the whole world, would it eventually start to understand language?"
"Hmm," says Adam. Then, after a long pause: "It's cold."
"Yeah. I'm freezing."
It's almost silent as we walk towards the city center. It's past midnight and as we approach the cathedral the only sounds I can hear are the distant humming noises of trucks outside shops; the creaking sound of men unloading blouses and sandwiches and packaged salads and coffee beans and newspapers so they can appear in the shops to-morrow, as if they came to be there by magic.
"Do we know each other?" Adam suddenly asks.
I pause, and then say: "In what sense?"
"I mean I thought I knew you when I saw you earlier today."
I take a deep breath: cold air in my lungs. "I thought the same thing."
"But I don't know you. I'm sure of it."
"Well..." I shrug. "Perhaps we did meet before and forgot."
"I wouldn't forget. I wouldn't forget meeting you."
"Adam...," I start.
"Don't say anything," he says. "Just look."
We're just walking past the cathedral gates. If you stop and look up where Adam's pointing now you can see Jesus looking down on you, carved in stone.
"It is amazing," I say, without thinking. "Even if you don't believe in all the rest of it, Jesus is a remarkable figure." Then I laugh. "That sounded so stupid and banal. Sorry. I'm sure no one even disagrees with that."
"You'd be surprised," Adam says.
"Oh," I say, suddenly remembering standing in the same spot earlier on, but looking at the gates, rather than up at Jesus. "Do you know anything about holy water?"
"That's a strange question."
"I know." We start walking again, turning off down a small cobbled street towards my flat. It occurs to me that maybe we are going to go back to my place and sleep together; maybe I could do that. But instead of my usual excitement I feel something else: the same feeling I got when I looked at my computer screen and saw how dirty it was earlier on. I'm dirty, and I'm busy doing something to help me escape. But we're walking on towards my flat, anyway.
"What do you want to know?"
"Um, well, all sorts of things, but mainly where I would get some."
"Get some?" I can't see his expression in the darkness but I can hear the frown in his voice. "Are you a Catholic?"
"No. I'm not religious at all. My mother believed in aliens."
"Ah."
"Yes. But why do you ask?"
"Only Catholics have holy water. You'd find it in any Catholic church."
"Not in the cathedral?"
"No. Not usually."
"I was sure I remembered fonts in the cathedral. I was going to go there before, but it was all locked up."
"There are fonts. But they're empty. The Anglican Church gave up on holy water centuries ago."
"Oh. So, presumably if you want to get holy water from a Catholic church you have to go in the day?"
"No. Not always. You..." He pauses. "Do you want to get some now?"
"Maybe. Yes. Maybe. I don't know."
"Can I ask why?"
"Probably best if you don't. It's, well, something you probably wouldn't approve of. Have you ever heard of the physicist George Gamow?"
"No. While you tell me about him shall we walk the other way? I'll show you where to find holy water."
"Really?"
"Yes. I've got a key to St. Thomas's. This way."
I follow him across a car park and through a small passageway onto Burgate. Burlem's house is just across the ring road, past St. Augustine's on a leafy residential road. I wonder what the house looks like now. I imagine it all boarded up and then realize that's silly: People don't board up houses nowadays. Maybe Burlem sold it. Maybe he's even there? I did go and knock on the door last year, but no one answered. Adam and I turn left and walk past the comic shop: a whole window display of superheroes and villains; good guys and bad guys. As we walk I put Burlem out of my head and instead tell Adam about George Gamow and how, when he was a kid, he once kept a Communion wafer instead of swallowing it and put it under his microscope to see if there was any difference between it and a normal wafer. I tell Adam that what I want with the holy water is somewhat similar to this—basically an experiment not at all in keeping with the spirit of Catholicism. Then we're at the church.
"I'll understand if you don't actually want to let me in now," I say.
"No. I like the sound of your experiment. And it doesn't matter to me, anyway." r />
Inside the church doors it's dark and smells of incense and cold stone. We don't go right inside: It turns out that the holy water is in a little font just inside the entrance. I notice that Adam crosses himself in front of an image of the Virgin Mary. I take out my vial.
"I'm sure this isn't something you should be letting me do," I say.
"It's only water," says Adam. "There are no rules to say you can't take some away with you. And like I said, all of this doesn't mean anything to me anymore."
But he doesn't watch as I dip the vial into the font. Instead he walks beyond me and starts fiddling with leaflets and copies of the Catholic Herald. There's a poster on the wall with the words Shrine of St. Jude on it. Adam lifts his fingers to it and touches it briefly. I don't think he realizes that I'm watching him. I look away.
"Can I ask why you have keys to the church?" I say to him as we leave.
"Oh, I'm a priest," he says. "Or, at least, I was. Can we go back to your place?"
Through someone else's eyes my kitchen must be a dark, fetid, oppressive space that smells of garlic and cigarettes. There's also a cursed book on the mantelpiece: a slim, pale volume that you don't even notice, if you are someone else.
"Sorry," I say to Adam, as we walk in.
But I'm not exactly sure what I'm sorry about. The thick gray dust on the top of the door frame? The broken arm of the sofa? The burn marks on the old kitchen work surfaces? The peeling green lino? I don't even see those things when I'm on my own. I want to open a window, but it's too cold. I want to turn on all the gas rings like I usually do, but I don't.
"Sorry it's so cold," I say.
"My place is freezing," says Adam. "I live on campus."
"Do you? Where?"
"I've got a room in Shelley College. It's tiny and smells of macaroni and cheese all the time. This is luxurious—believe me."
"Would you like some coffee?" I ask him.
"Just some water, please, if that's all right."
I fill a glass with tap water for Adam and then put on coffee for myself. A train goes past outside and the thin sash window rattles gently. I see a tiny movement in the corner of the room—there and then gone, like a phantom particle. A mouse.