The Popularization Bias

There are an awful lot of caveats that apply to the No Free Lunch theorem. Is it really very applicable in practice? If you're just going to use it as a hand-wave concept, I think it's more honest to use TANSTAAFL and make your lack of rigorous mathematical backing clear.

So, can anybody list a few lessons we can draw from the NFL theorem?

Occam's razor means that the no free lunch theorems are practically irrelevant.

Hypercomputation seems like a misguided attack on the Church-Turing thesis to me. If nobody can build a hypercomputer - and there's no evidence that anyone ever will be able to - then I am not sure I can see what the point is.

Wasn't as enlightening as the abstract made it sound.

Good find, thanks!

I'm curious, was anyone else aware of cooperative game theory, before I mentioned it here?

I had vaguely heard of it and the main result you presented, but I didn't find it very interesting - and I still don't, even after your post. (The black hole material was much more interesting.)

In comparison, the first time I read about the Prisoner's Dilemma and the Tragedy of the Commons, my reaction was: 'this is amazing! It provides a new way to look at just about everything - littering on sidewalks, war, traffic & SUVs, cheating on taxes...' For a year or two, I saw everything through that lense.

Yes. Not to sound like a jerk, but I didn't realize it was so poorly known.

On the issue of nuggets of knowledge left, I think it's more so the case that we just don't know where we'll find them or that they aren't already well known. It will take something that will make someone who is aware of the details of some field realize that a popular account is needed because even his/her fellow smart people don't know about it.

I'd read the Wikipedia page before, for some reason it didn't seem very interesting to pursue further.

Yup. Although I think that the core) is possibly a more useful concept than the Shapley value. (I actually had a vague suspicion it could be useful for Toby and Nick Bostrom's work on dealing with moral uncertainty, but never bothered to follow up.)

Yes, when I first learned about the Shapely value, I bothered everyone I knew by telling them all excited-like about it when they obviously didn't much care. :)

Michael Sipser's Introduction to the Theory of Computation is an extremely friendly introduction to theory of computation, including complexity theory and computability theory. As opposed to Garey and Johnson, it seems broader and shallower, covering computability theory (incl. space complexity and other non-NP-Complete topics) as well as complexity theory, and probably in a much friendlier fashion. It's one of the few compsci books I've ever read that I would describe as a "page turner": it was so interesting and readable that I couldn't put it down when reading it, and I still like to pick it up from time to time just to reread sections for pleasure.

[The 1st edition is much cheaper than the 2nd edition for anybody interesting in buying ($10-$20 used, versus >$55 used on 2nd edition or $115 new).]

That's not a bad story, but the author seems more interested in using black holes as exotic locales with cool "special effects", rather than exploring the implications of their physics. The reader walks away entertained, but not really having learned anything about black-hole thermodynamics.

The point is that a black hole is much colder than interstellar space, and its temperature decreases as its mass increases. This coldness implies that it takes much less energy to dump a certain amount of entropy into a black hole than into interstellar space. Of course you probably don't want to ship that entropy across interstellar distances before dumping. That would likely wipe out any savings. You'd create a black hole close by, or build your civilization around an existing one.

Regarding this discussion, I'm totally confused what people are talking about. It sounds like you want to take some of your excess energy and throw it into a black hole. Wouldn't it be smarter to give it to me? How can energy be "excess"?

+1; indeed, this is interesting from an scifi-itch-scratching viewpoint, but I guess we have the next 10^6 years to worry about the details.

Anyway, I like LW for bringing such things to my attention (thanks Wei_Dai!), but apart from being interesting, this seems not like an idea that need mass-popularization, or?

That has as much relevance to black-hole negentropy as Demolition Man does to cryonics. In science fiction, the inability to explain something is indistinguishable from attributing it to magic.

In Dr. Who, the Time Lords used a black hole as a 'mysterious energy source'.

Same for the Ori in the SG-1 episode Beachhead (transcript here; summary and transcript of prior black-hole episode here and here, which may partly explain the writers' thinking).

That looked to be interesting until I glanced down at Figure 1, which reads:

Entropy and biodiversity are mathematically equivalent, making tropical forests the most entropic [entropy exporting] environments on Earth.

Eeek! Tropical forests the most entropy-exporting? Not, say, the 1000 C regions below the earth's surface? Not volcanoes or geysers?