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Argency comments on Harry Potter and the Methods of Rationality discussion thread, part 16, chapter 85 - Less Wrong
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Perhaps a better suggestion is that his "down time" involves synchronisation of his memories/program state between Horcruxes, and it gets worse the further Pioneer moves from Earth... Even with magic, there's no way round speed of light limits.
Quirrell probably wasn't expecting that, which could explain why his days as a Dark Lord are numbered (and also explains why he's desperate to train up Harry as a replacement, assuming his goal of uniting the wizarding world is sincere).
I'm also wondering if the 6 hour limit of Time-Turners is a crucial variable somehow, so that he could synch at distances up to 6 light-hours, but not otherwise. Does anyone know when the Pioneer 11 probe got more than 6 light-hours away from Earth? Was it around 1991/1992??
It's been on its way since April 1973 (for right about 39 years), so assuming a steady speed, it would've passed the six-hour limit roughly 19,5 years ago, or in late 1992.
What time is it in terms of Potter Time? The books take place a few decades ago but I forget exactly when.
April 1992.
Given that Pioneer fooled around in the Solar System for a while, making flybys of Jupiter and Saturn, our calculation should be a bit different. 1992 is a useful lower bound, which we arrived at by calculating what would happen if Pioneer took a straight path out into interstellar space. In fact, it flew by Saturn in September 1979. A bit of trigonometry tells me that if it left Saturn in a straight line tangent to that planet's orbit, it would probably reach the critical distance some time between '95 and '97, depending on Earth's own position in its orbit. This rough map seems to suggest that it did take that approximate path, but it's hardly accurate. If Pioneer skirted closer to the sun again, inside Saturn's orbit on it's way out then the critical distance comes later, but if it veered away harder then it comes earlier.
I had typed my calculations up, but I lost them just now when I accidentally pressed the back button. Hell's bells and buckets of blood.
Anyway, basically what this tells us is that Quirrel probably has at least a few years of grace before Pioneer gets too far away, if that is in fact what's going on. I think there's a fair likelihood that this theory is correct, but given what I've said here, I don't think the timing of the Pioneer's critical distance should be counted as strong evidence in favour of that.
Thanks for the calculations... I had a rough guess that 6 light-hours was reached some time in the 90s, but didn't know enough about the flight-path to check this.
I believe that the 6 light-hour limit only makes sense as a theory if Quirrell is going to hit it in this school-year (and it explains why it is impossible for him to continue as a teacher next year). If he's still got a few years grace it doesn't work so well, and I suspect that Eliezer would have done a detailed calculation if he was relying on this theory, rather than a rough-and-ready / linear interpolation calculation.
However, I still like the idea of Quirrell being hoisted by his own genius petard (and by his hatred of science, since if he'd bothered to study it, rather than just using it, he might have avoided that mistake).
How's he supposed to know that the Horcrux connection craps out at six light-hours? Presumably he's the first to have a Horcrux anywhere but Earth.
From Chapter 61:
If information cannot travel back more than six hours, and a "soul" (stored on a Horcrux) is information (as Quirrell describes it), then it is a reasonable guess that the soul cannot travel over a spatial separation of more than 6 light-hours. Further than that, and it seems the soul parts must fall out of synch, though exactly what happens then is anyone's guess. Does Quirrell die? Are there two separate Quirrells, one stranded permanently on Pioneer, and the other on Earth? Can the one on Earth be killed, even if the one on Pioneer is never destroyed?
This does seem to be a constraint that exclusively affects the time-turners. Otherwise prophesies wouldn't be possible. It also seems like it's an artificial rule rather than a deep law of magic because after the Stanford Prison experiment, Bones tells Dumbledore that she has information from four hours in the future and asks whether he'd like to know it. That there is relevant information from four hours in the future is information from the future - she would not have said that if it were otherwise, so it seems there must be exemptions of that kind.
Alternative hypothesis: prophesies are jive, and Eliezer didn't think of the other thing.
That's information to a careful logical thinker. There's a lot of evidence that magic to a large extent acts as a naive person might expect reality to act. Broomsticks and the bag of holding are both examples of this.
More then 6 hours in what reference frame?
The reference frame of the Heart of Magic, naturally.
Returning to this thread after a few months...
I see Eliezer has responded in a way which kills my theory stone cold. (Though it was dead anyway if the 6 light-hour separation by Pioneer wasn't reached in 1992.)
But basically what I was thinking was this. Consider any two space-time points x and y. Either they have a time-like separation, or a space-like separation or a null separation. If they have a space-like separation then there is a particular inertial reference-frame in which they are only separated in space, not in time. If the spatial separation in that frame is > 6 light-hours, then information cannot travel from x to y. (Or, if you want to think of it in terms of a causal graph, and Pearl's intervention calculus, then every intervention to the graph at x will leave events at y unaltered.)
Incidentally, this formulation implies the rule that "information can't go back in time more than 6 hours" and implies it in any inertial reference frame. For if information could travel from x to a point z, more than 6 hours in the past of x (but at the same place) in some reference frame, then it could be sent further along a future-pointing null vector from z to y (by an ordinary light-beam), where y is > 6 light-hours from x in the same reference frame. So the restriction of "no spatial jumps > 6 light-hours" neatly implies "no temporal jumps back > 6 hours".
Basically, this looks something like the Minkowski interval formulation: there is no privileged reference frame, just a new constant of nature (i.e. whatever 6 light-hours translates to in Planck lengths).
Why the heck is this being voted down? It's a perfectly valid question! You could have some Minkowskian interval that Time Turners can't go further back than, and it would make sense in terms of Special Relativity, but there's no obvious analogy for a maximum spacelike separation being built into the laws of magic.
I may be willing to put Time Turners in my fic - I may even be willing to swallow the single-world interpretation of QM which that necessarily implies - but even I'm not going to give magic a privileged reference frame, or talk like "hours" are an intrinsically meaningful measure. Special Relativity is... I mean... it's over the local properties of the variables on which everything else is built, it's the stuff that the fabric of reality is locally made of. It's like having Harry not be made of atoms.
Could this constraint apply in other ways? Suppose magic is the result of something that responds to the wishes of witches, as suggested at one point. If that something is Earth-based, perhaps a wizard on an outbound spacecraft would stop being able to do magic when he reaches 6 light-hours out. An interesting experiment.
Harry might be able to realistically do an experiment similar to this as a first year if there is a magic spell that lets you communicate with an object. He could use a spell to accelerate that object to a very high speed and then check in on it as it approaches the 6 light-hour point.
Idea: Dumbledore says
Maybe the Pioneercrux is dragging the shade-part into space.
...I meant April 1992 is when Taboo Tradeoffs happens.
I know. Gastogh made the 1992 calculation. I was making the point that although Gastogh calculated Pioneer to have reached the critical distance of six light-hours in 1992, and you pointed out that Taboo Tradeoffs was happening in 1992, we shouldn't take this coincidence as evidence in favour of the theory that communication between horcruxes and their master is limited to light speed, and that this is somehow related to time turners. I don't necessarily think either of you support such a theory, for that matter, nor am I making any argument for or against that theory itself.