Garbage-Collecting the Metaverse

[ENS] [ENS students] [David Madore]
[Mathematics] [Computer science] [Programs] [Linux] [Literature]

``You see,'' I said, suppressing a small yawn, ``I happen to be God.''

``God. Really.'' answered Mark, seeming equally bored. ``And I suppose you mean that literally.''

``Quite literally. Omnipotent, omniscient, all that junk.''

``Miracles and all? Can you make, like, that red car over there: can you make it disappear?''

A woman came running to the car, entered it and rode away in a hurry.

``Oh well,'' said Mark, ``no matter. Any other one will do.''

I gave him a reproachful look.

``I'm sorry, Mark, one is enough. I won't empty this entire parking lot.''

He stared at me without seeming to undertand — and suddenly he smiled, as if amused.

``You mean to say… The woman… That was your doing?''

``That's what you wanted, wasn't it? The car left.''

He found the idea funny, but I could see he was — slightly — uneasy.

``I was expecting… I don't know. I thought you would wave your hands, that some smoke would appear, perhaps a loud noise… You know, magic.''

I eyed him with distaste.

``That is the way of the trickster, Mark. Of the charlatan. I don't need that nonsense. I made the rules, so I don't want to break them. And I don't need to, because I control everything.''

He looked back at me with definite suspicion and unease.

``What is my social security number?'' he asked, suddenly.

``Mark, I don't have any idea how many digits there are to a social security number in this country.''

``So much for omniscience, then.''

I sighed.

``All right.'' I said. ``If you really want this. It's 20010401-504564Q. I just won't say which country we're in.''

He paled visibly.

``That number is correct. You must have learned it somewhere… But I don't see how you.''

``Look, Mark,'' I said, with a trace of impatience, ``if you want to be convinced that I am God, just say so. I won't waste my time convincing you with magician's tricks — I'll just make you convinced.''

``All right, then make me convinced.''

``Now you are, aren't you?''

Of course he was.

``Oh my God. You are He.''

``Thank you for admitting this.'' And I added, ``No need to get into a fit of veneration, either.'' as he was about to do this. ``Just behave normally. What were we speaking of, a minute ago?''

``I was about to ask: what do you mean you won't say which country we're in? You can't not know that.''

``Oh yes. That remark was not meant for you. Just don't speak the country name, or I'll have to check the facts for the place, and possibly go back in time to correct the number.''

``Not meant for me? But I'm the only one around. To me, what you say doesn't seem to make sense. With due respect, of course.''

``To you it doesn't. Never mind, this really isn't important. That's just the annoying things you get when you create a world using lazy evaluation, like I do.''

``Lazy evaluation?''

``You know, the famous problem about the tree falling in the forest when nobody can hear it: does it make any noise? Well, it doesn't. Matter of fact, the tree doesn't even exist until I describe it.''

To illustrate my remark, I pointed at a beautiful oak tree overshadowing the parking lot.

The beauty, however, was lost on Mark. He was becoming more and more agitated.

``What does all this mean? Are you going to tell me the world's about to end?''

``Ah, thank you for mentioning this. Actually, it is. In just over a few minutes.''

There was just enough humor in my voice to let Mark relax.

``Oh, is it? So you're going to destroy the world? Call an army of demons? Open the Seven Seals and blow the Seven Trumps?''

``No, sorry. I despise that sort of inelegant pyrotechnics. Who needs it? No, the world will not be destroyed, it will merely cease to exist. It will simply be garbage-collected.''

``GARBAGE-COLLECTED? What is that supposed to mean?''

``Let me see. First of all, I create a bed…''

I turned away from the window, and looked at the cozy bed lying right behind me.

``Looks comfortable enough.'' I noted.

``But you didn't create that, it always&mdash''

``Mark, please. This is what I mean by creation using lazy evaluation. Up to a second ago, there was nothing behind us, and we weren't even sitting by a window. But of course the bed has always been here: you wouldn't think I'd have it brought here while we were looking away, would you? Nor would I make it appear out of thin air? I told you I don't like breaking the rules.''

``And how will you destroy the world without breaking the rules?''

``I said I wouldn't destroy it. I will only cause it to be garbage-collected. Lazy garbage collection, of course: virtually nothing to be done; only a few bits will remain, a copy of this conversation, for example, with no pointers to elsewhere. All I've got to do is go to sleep.''

``And when you wake up?''

``I won't ever wake up. Not because I'll die or anything. Merely because the waking up bit is removed in the garbage-collection. This world will already have ceased to exist — in fact, it will never have existed — by the time I wake up, so I never will.''

``And what will I become?'' asked Mark, suddenly chilled.

``I won't let you be garbage-collected, worry not. Mind you, I could. It wouldn't hurt or anything. But I'll use you in the next world. Now, if you'll excuse me, the Apocalypse is in just a few seconds, I've got to go to sleep.''

And, without further comment, I went to bed, and fell asleep immediately. And this is what I dreamt of:


``I like it.'' said Mark. ``Nice idea to recount a conversation between us two. But I don't quite get it.''

He paused for a second to contemplate the paper. And then he asked:

``In the first place, what in the world is a car? Or a tree? Or a window and a bed for that matter?''

``Uh? Oh, just some things I invented. Too bad I didn't have the time to describe them in more detail. They're rather amusing.''

``A bit alien, though. But the part I mostly don't understand is the end. I like your idea of the end of the text corresponding to the end of the world. But what are you supposed to have dreamt of?''

``Why, this.''

``What this?''

``The conversation we're having now.''

``What? But this isn't a dream!''

``Actually, you're right. It's more like an HTML file.''

And with this last cryptic comment, I left the schnubkra.


[ENS] [ENS students] [David Madore]
[Mathematics] [Computer science] [Programs] [Linux] [Literature]

David Madore
Last modified: $Date: 2000/01/09 02:57:34 $