Heh, clever. In a sense, iron has the highest entropy (atomically speaking) of any element. So if you take the claim that an aspect of solving intergalactic optimization problems involves consuming as much negentropy as possible, and that the highest entropy state of space time is low-density iron (see schminux's comment on black holes), then Clippy it is. It seems though like superintelligent anything-maximizers would end up finding even higher entropy states that go beyond the merely atomic kind.
...Or even discover ways that suggest that availability of negentropy is not an actual limiter on the ability to do things. Does anyone know the state of that argument? Is it known to be true that the universe necessarily runs out of things for superintelligences to do because of thermodynamics?
There is a theoretical limit on how much negentropy is required to erase a bit. However, it depends on temperature. Unless the expansion of the universe has a limit, the universe will get arbitrarily cold, and computers could be arbitrarily efficient. Theoretically, you could make a finite amount of energy last an infinite number of computations.
As most LWers will know, Clippy the Paperclip Maximiser is a superintelligence who wants to tile the universe with paperclips. The LessWrong wiki entry for Paperclip Maximizer says that:
I think that a massively powerful star-faring entity - whether a Friendly AI, a far-future human civilisation, aliens, or whatever - might indeed end up essentially converting huge swathes of matter in to paperclips. Whether a massively powerful star-faring entity is likely to arise is, of course, a separate question. But if it does arise, it could well want to tile the universe with paperclips.
Let me explain.
To travel across the stars and achieve whatever noble goals you might have (assuming they scale up), you are going to want energy. A lot of energy. Where do you get it? Well, at interstellar scales, your only options are nuclear fusion or maybe fission.
Iron has the strongest binding energy of any nucleus. If you have elements lighter than iron, you can release energy through nuclear fusion - sticking atoms together to make bigger ones. If you have elements heavier than iron, you can release energy through nuclear fission - splitting atoms apart to make smaller ones. We can do this now for a handful of elements (mostly selected isotopes of uranium, plutonium and hydrogen) but we don’t know how to do this for most of the others - yet. But it looks thermodynamically possible. So if you are a massively powerful and massively clever galaxy-hopping agent, you can extract maximum energy for your purposes by taking up all the non-ferrous matter you can find and turning it in to iron, getting energy through fusion or fission as appropriate.
You leave behind you a cold, dark trail of iron.
That seems a little grim. If you have any aesthetic sense, you might want to make it prettier, to leave an enduring sign of values beyond mere energy acquisition. With careful engineering, it would take only a tiny, tiny amount of extra effort to leave the iron arranged in to beautiful shapes. Curves are nice. What do you call a lump of iron arranged in to an artfully-twisted shape? I think we could reasonably call it a paperclip.
Over time, the amount of space that you’ve visited and harvested for energy will increase, and the amount of space available for your noble goals - or for anyone else’s - will decrease. Gradually but steadily, you are converting the universe in to artfully-twisted pieces of iron. To an onlooker who doesn’t see or understand your noble goals, you will look a lot like you are a paperclip maximiser. In Eliezer’s terms, your desire to do so is an instrumental value, not a terminal value. But - conditional on my wild speculations about energy sources here being correct - it’s what you’ll do.