The Quantum Thief

Except that I don’t get a chance. She points at the small table and chair in front of the balcony. ‘Sit.’ She places the Watch in front of me. ‘Talk to me. What in Dark Man’s name happened at the agora?’ She clenches and unclenches her fingers. I swallow.

‘All right. I saw myself.’ She raises her eyebrows.

‘It was not another memory, not like on the ship. It must have been a gevulot construct of some kind: somebody else saw it too. It led me to the garden. So clearly, we are getting somewhere.’

‘Perhaps. It did not occur to you to fill me in on this? Are there any reasons for me to let you out of my sight again? Or not to recommend to my employer that we should take off the silk gloves and take a more … direct approach with your brain?’

‘It was … sudden.’ I look down at the Watch. The sunlight glints off it, and again, I notice the engravings on the side. ‘It felt … private.’

She grabs my face with impossibly strong fingers and turns it up. Her eyes look unblinking into mine, angry and green.

‘As long as we are in this together, there is no private. Do you understand? If I need to know, you will tell me your every childhood memory, every masturbation fantasy, every teenage embarrassment. Is that clear?’

‘I do wonder,’ I say slowly and carefully, ‘if there is something affecting your professionalism. And I would note that I’m not the one who screwed up the Prison exit. I’m just the one who got us out of it.’

She lets go and looks out of the window for a moment. I get up and get a drink from the fabber, Kingdom-era cognac, without offering her a glass. Then I study the Watch again. There are zodiac symbols, in a grid of seven by seven, Mars, Venus, and others I don’t recognise. And underneath, cursive script: To Paul, with love, from Raymonde. And that word again, Thibermesnil, in copperplate typeface.

Could you have a look at these? I whisper to Perhonen. You will still talk to me without hitting me, right?

I don’t need to hit you, the ship says. I have lasers. I’ll see what I can find. Its tone is unusually terse: I’m not surprised. I tell myself it’s the cognac alone that makes my face burn.

‘All right,’ Mieli says. ‘Let’s talk about this thing you stole.’

‘Found.’

‘Whatever.’ She holds it up. ‘Tell me about this. The Oubliette data I have is clearly obsolete.’ Her tone is colourless. A part of me wants to break that icy veneer again, dangerous or not, to see how deep it goes.

‘It’s a Watch. A device that stores Time as quantum cash – unforgeable, uncopyable quantum states that have finite lifetimes, counterfeit-proof, measures the time an Oubliette citizen is allowed in a baseline human body. Also responsible for their encrypted channel to the exomemory. A very personal device.’

‘And you think it was yours? Does it have what we need?’ ‘Maybe. But we are missing something. The Watch is meaningless on its own, without the public keys – gevulot – inside the brain.’

She taps the Watch with a fingernail. ‘I see.’

‘This is how it works. The exomemory stores data – all data – that the Oubliette gathers, the environment, senses, thoughts, everything. The gevulot keeps track of who can access what, in real time. It’s not just one public/private key pair, it’s a crazy nested hierarchy, a tree of nodes where each branch can only by unlocked by the root node. You meet someone and agree what you can share, what they can know about you, what you can remember afterwards.’

‘Sounds complicated.’

‘It is. The Martians have a dedicated organ for it.’ I tap my head. ‘A privacy sense. They feel what they are sharing, what is private and what isn’t. They also do something called co-remembering, sharing memories with others just by sharing the appropriate key with them. We just have the baby version. They give the visitors a bit of exomemory and an interface to it, reasonably well-defined. But there is no way we can appreciate the subtleties.’

‘And why would they do this?’

I shrug. ‘Historical reasons, mainly: although not much is known about what exactly happened here after the Collapse. The commonly accepted version is that someone brought a billion gogols here for a private terraforming project and set themselves up as a King. Until the gogols rebelled. Anyway, the fact that the gevulot system is in place is pretty much why Sobornost has not just eaten this palace yet. It would be too much trouble to decrypt everything.’

All right, you two, says Perhonen. Sorry about the delay, I didn’t want to interrupt. The symbols are astrological. The exact sequence only appears in one source, Giulio Camillo’s Memory Theatre. It’s an occult system from the Renaissance. Thibermesnil is a castle in France. Here are the details. She sends a spime down our neutrino channel. Mieli looks at it and leaves it hanging in the air, between us.

‘Fine,’ she says. ‘So, what does all that mean?’

I frown. ‘I have no idea. But I think everything we need is in my old exomemory. What we need to do is to figure out how to get to it. I think I need to become Paul Sernine again, whoever he was.’ I pour myself some more cognac.

‘And where do you think your old body is? Did he – you – take it with you when he left? And what is the point of those markings?’

‘Could be. And as for the symbols, I don’t know – I always had a taste for theatrics. I’m certainly not getting any flashes from them.’ I feel slightly disgruntled at my past self. Why the hell did you have to make this so complicated? But the answer is obvious: so that secrets would be secrets. And hiding them among other secrets is a textbook way to do it.

‘So there is no way we could brute-force this, to get access to your memories through the Watch? We could use Perhonen to—’

‘No. There are three things they do better than anyone here: wine, chocolate and cryptography. But’ – I lift my index finger – ‘it is possible to steal gevulot. The system is so complex it’s not perfect, and sometimes you can trigger whole cascades of gevulot branches by getting a person to share the right thing with you at the right time. Social engineering, if you like.’

‘It always comes down to stealing for you, doesn’t it?’

‘What can I say? It’s an obsession.’ I frown. ‘We even know where to start: I had a significant other here. But we do need some proper gevulot-breaking tools. Maybe more: using this toy gevulot sense they gave us would be like trying to pick a lock with a brick in the dark. So I think it’s time you contacted your employer to put us in touch with some gogol pirates.’

‘What makes you think that—’

‘Oh, come on. Your employer is from Sobornost, clear as day, maybe some powerful copyclan, out to score points with the Founders. He/it/they – whatever pronoun they use these days – will have contacts with the pirates here, the Sobors are their main customers.’ I sigh. ‘I never cared much for them. But if you want to dig up treasure, you have to be prepared to get your hands dirty.’

She folds her arms. ‘All right,’ she says. ‘I will point out – to deaf ears, I’m sure – that it is not particularly wise or healthy for you to ask questions or make inferences about our mutual … benefactor.’ There is a trace of irony in her voice when she says the last word. ‘In any case, it seems there are three things we can do. One: figure out why you would leave the Watch to yourself. Two: try to find your old corpse. Three: get in touch with the only people on this planet with less morals than you.’

She gets up. ‘I will see what I can do about option three. In the meantime, you and Perhonen will work on number one: we will leave option two until we know more. And get yourself cleaned up.’ She turns to leave.

‘Wait.’

‘Look. I’m sorry I escaped. It was a reflex. I haven’t forgotten my debt. You have to understand that this is a little strange.’

Mieli looks at me, and smiles cynically, but does not say anything.