Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Turing Oversold?

people.idsia.ch

Post reply on HN
Print view View original

201–210 of 311 posts

Re: Turing Oversold?

#201

Post by hardlianotion »

codeflo wrote: post #113
bjornsing wrote: post #87

Earlier quoted context omitted.

> The Turing machine has a tape of unbounded size so can’t be built simpliciter. On the contrary, I think this is one of the advantages of Turing’s model: I can imagine standing there in my garage looking on as my universal Turing machine is running low on tape on the left side, and then simply attaching a new roll of fresh empty tape at the end, holding it as it is fed into the machine. :) It’s simply the least leak…

Exactly this. Unbounded doesn't mean infinite, and people are sometimes confused by the distinction.

Including me. What is the difference?

Re: Turing Oversold?

#204

Post by thom »

cybernautique wrote: post #185
generalizations wrote: post #172

Earlier quoted context omitted.

I'm still a little confused. It seems like Turing came up with something that works, and clearly fulfills precisely what Godel and Church and Turing were all looking for; but it also seems like it's a mathematically inelegant solution. Is it possible that in the future we'll find a way to show that Gödel's mu-recursive functions or Church's lambda calculus also precisely describe 'what a machine can do'? If so, it se…

I'm convinced that David Harland's Rekursiv[1:] machine _is_ the manner by which lambda et al. might be implemented at the machine level. Unfortunately, Rekursiv seems to have died an ignominious death, with the last Rekursiv chip having fallen off the side of a steamboat (apocrypha; I remember having read this, but I'm unable to find the original citation.) The Rekursiv advantage is its ability to do recursion on th…

Thanks for this link, really interesting stuff. For a while there was a fashion in OS research for orthogonal persistence but this is much deeper and more elegant.

Re: Turing Oversold?

#205

Post by mrtranscendence »

TeMPOraL wrote: post #127
sandwall wrote: post #75

Earlier quoted context omitted.

Story telling is how our society has transferred information since we started to communicate-- understanding the map is not the territory, nor should it be. A beautiful narrative can convey important kernels more efficiently than endless minutiae-- Awareness of this is important and elaborations are helpful for those interested in the details. I'm reminded of, "The Glass Bead Game," which discusses an academic societ…

Arguably our storytelling was an efficient hack in an age before writing. A story is a very high-overhead, low SNR way of communicating kernels of truth, but it's robust over time, so it allowed transfer and accumulation of knowledge across societies and generations. But then we've invented and perfected writing, developed symbolic languages and notations (e.g. math, musical), long-duration storage media for text, an…

Stories place ideas into context, not only making them easier to remember (as mentioned by another comment) but also easier to understand. Analytic philosophers are used to dry, precise language, but even they often rely on scenarios and narratives -- this can help reveal what the reader thinks intuitively and bring that into sharper contrast. By remaining story-free you're giving pedagogy the short shrift.

What has empirically brought more folks into careers in science, dry textbooks foisted by teachers or Star Trek? I'd argue Star Trek and science fiction more generally. You can chalk that up to human failings if you like, but inspiration is a need that can't be avoided if you wish to convince.

Re: Turing Oversold?

#206

Post by cybernautique »

thom wrote: post #204
cybernautique wrote: post #185

Earlier quoted context omitted.

I'm convinced that David Harland's Rekursiv[1:] machine _is_ the manner by which lambda et al. might be implemented at the machine level. Unfortunately, Rekursiv seems to have died an ignominious death, with the last Rekursiv chip having fallen off the side of a steamboat (apocrypha; I remember having read this, but I'm unable to find the original citation.) The Rekursiv advantage is its ability to do recursion on th…

Thanks for this link, really interesting stuff. For a while there was a fashion in OS research for orthogonal persistence but this is much deeper and more elegant.

Absolutely! As mentioned, I'm very much a novice of computer architecture. It kinda blew my mind that Rekursiv was unique in its abilities. Also fascinating are LISP Machines, which seem to have received quite a bit of love from HN already.

If I may ask, from your perspective, what's more elegant about Rekursiv's design? Is it the philosophy or implementation? I'd also love any links to orthogonal persistence!

Re: Turing Oversold?

#207

Post by mcguire »

KingOfCoders wrote: post #124
bo1024 wrote: post #122

Earlier quoted context omitted.

I don't think it's important to quibble over who's overrated or underrated among these giants of math and CS who already get tons of recognition (I'm glad Schmidhuber brings many other historical names into the narrative). However, yes, I do think that 'mechanization' or physical implementation is a crucial piece of Turing's contribution that is wrongly ignored in this article. And I think without mechanization, ther…

I can only repeat my comment from down: "Likewise, Konrad Zuse never got a Turing award despite having created the world's first working programmable general computer 1935-41. [...] It was pointed out that none of the computers built during the 1940s were influenced in any way by Turing's 1936 theoretical paper, [...]"

I don't believe anyone has received a Turing award for creating a working computer.

Re: Turing Oversold?

#208

Post by mcguire »

netcan wrote: post #38

Just the references here are probably an amazing resource for early computer science, and I'm not going to argue against such a force. Seems to be a lot of uneasiness, of late, about the way credit is allocated in science. IMO, it's mistaken to point this at the top: nobel laureates, heroic icons like Einstein or Turing. These figures are supposed to be idolized and idealized. Yes, this is "untrue," technically. But,…

"Seems to be a lot of uneasiness, of late, about the way credit is allocated in science."

This is always been the case---medieval and renaissance thinkers would publish anagrams of their key findings because they didn't want to give someone else the advantage of knowing the finding but also wanted to prove that they thought of the idea. IIRC, Isaac Newton did not publish any of his findings until someone else threatened to publish their independent results. And he's known as the creator of calculus because the British Royal Society got into an academic slap-fight with the French.

Re: Turing Oversold?

#209

Post by simorley »

netcan wrote: post #38

Just the references here are probably an amazing resource for early computer science, and I'm not going to argue against such a force. Seems to be a lot of uneasiness, of late, about the way credit is allocated in science. IMO, it's mistaken to point this at the top: nobel laureates, heroic icons like Einstein or Turing. These figures are supposed to be idolized and idealized. Yes, this is "untrue," technically. But,…

> Seems to be a lot of uneasiness, of late, about the way credit is allocated in science.

Of late? You should read up on Newton/Leibniz hysterics over who invented calculus. The arguments over who invented the first light bulb, car, etc. Whether greek knowledge ( the foundation of western civilization ) originated in the near east or even in india. Heck, people still argue about who "discovered" america first. There is national, religious, ethnic, racial, gender, sexuality pride tied to "priority". It's not just in science/math, it's applies to everything.

> These figures are supposed to be idolized and idealized

Why? They weren't particularly good people. Neither were saints.

> Achilles elevated Greece by giving Greeks something to collectively aspire to or adulate.

Are you talking about science/knowledge or politics? But you are right on the point. It's what this is all about at the end of the day. Politics.

Without politics, the discovery/knowledge would be what is important. Because of politics, the people become the focal point.

Re: Turing Oversold?

#210

Post by hansvm »

hardlianotion wrote: post #201
codeflo wrote: post #113

Earlier quoted context omitted.

Exactly this. Unbounded doesn't mean infinite, and people are sometimes confused by the distinction.

Including me. What is the difference?

The usual difference is just predicate ordering -- (1) for every program there exists a tape big enough vs (2) there exists a tape big enough for every program. In the first case, each individual (valid) program can get by with a tape of _some_ fixed length, but there's no bound on how big that requisite length might be. In the second case, since the tape requirements can be arbitrarily high you would need a legitimately infinite tape to service all possible programs.

IMO the given example muddies the waters a bit by conflating the conceptual tape a given machine is running on (which might be infinite for non-halting programs) with the physical tape you've used so far (for which it suffices for such tape to be finite at any fixed moment in time, though the amount needed might grow unboundedly as time increases).

Post reply on HN