Re:New maths never had practical applications
on
Fields Medals awarded
·
· Score: 2, Insightful
Of those "pure mathematical" developments of twenty years (or forty years) ago, what has been used outside mathematics?
Off the top of my head, I'd say lattice and group theory for designing error correcting codes. The Solomon-Reed ECC used in CDs and DVDs was designed from the structure of a special lattice.
A lot of "useless" theories (much more "concrete" than topology, though: Collatz bases, Cylindrical Algebraic Decomposition and whatnot) ended up in Computer Algebra Systems in very "useful" tasks as factoring polynomials and solving equations.
And, who knows, maybe the topological approach to Quantum Gravity does pan out in the end.
I think these 7 billion should be "accounted" as the savings O'Neill is making for American carpenters and plumbers by not lending any money to Argentina.
Not that I, personally, want any more IMF cookies in the Argentine cookie jar, but come on! Now I'm very tempted to say the word hypocrisy. But I will refrain from it.
Interesting. Use two nested loops, the outer iterating over differences from N-1 to 0 (that is, the N-1'th difference, then the N-2'th and so to the 0'th difference), the inner building the table of differences over the array.
It's O(N^gr(P)), where P is the polynomial to compute, and gr(P) is its degree. As it should be.
He was the Euclid of our times. Reading his writings I get the same feeling of economy, conciseness, clarity, effectivity that I do when reading the Elements. His calculational style of proof is, to me, entirely on par with Euclid's use of the Theory of Proporions.
I hope it won't have to take two thousand years before we recognize his fundamental brilliance.
Could be. I thought Time was about the undying japanese woman and the crystal flowers...or is it the same book and the other one is about something else entirely?
Bah, my memory is like a sludgy swamp: everything in there decays to the same undifferenciated matter. The point is, I didn't like either book much, compared to Vacuum Diagrams. Don't get me wrong: both Manifolds are very good, very dark and depressing; but Vacuum Diagrams is more poetic, I guess is the word.
I gave up my hopes for science fiction a long time ago, anyway. It's all oh-so-marketable now. Seeing that Rowlands woman winning the Hugo last year was a sad sign-o'-the-times.
Similarly, by the fact that the vacuum near us hasn't decayed, you can make a pretty strong argument for the observed state of vacuum being the lowest reachable state.
Stephen Baxter's novel Manifold: Space toys with the idea that the vacuum is at a metastable level. The book ends with the release of the vacuum to its actual ground state.
Hmm...no, not for the American variety of Christians (what do you call them? Baptists?). Actually, the Catholic Church chose that path of reconciliation between doctrine and secular science, but by saying that the Bible must be read in a "poetic" light, or under a metaphoric interpretation. And that is precisely what American Christians reject: they believe the Bible is God's revealed, literal truth against which everything else is measured.
chances are the Virgin Mary wasn't a virgin either
She was a virgin! When she was called Aphrodite, she begot Pan on Hades and then bathed herself on the waters off Paphos and regained her virginity. Only that in Canaan she was called Mariam, her godly husband was Yahweh, or Baal (who also lived in a mountain of fire, as Exodus tells us) and his son was called Yeshu (who was a lamb, and died in Passover).
No, no, no, no! Please don't inflict upon yourself the pain of having to use AppleScript! Take a look at MPW instead.
Highlights: free (as in beer), integrated shell and text editor, handles very large files (4G), integrated C/C++/Asm for 68k and PPC, batch text editing, standard I/O support, "live" windows tied to the filesystem, Shell language for scripting, can send/receive AppleEvents...
Short answer: because not everybody is running X on Mac hardware.
Long answer: as much as I would like to use X, the sad truth is that MPW is far superior as a command-line shell than anything else on the known universe. In particular, I rely heavily on it for database development. Also, in my W&B G3 Classic feels much more responsive than X (I haven't tried 10.1 or later, though). MPW + Perl is like a dream environment.
Oh, I forgot: I still have to support legacy Classic applications (mostly, 4th Dimension externals), and I just can't compile and test them under X.
I think the key to Internet publishing is patience. If your work is a roar, you won't get a big exposure to it as fast as with a printed edition. On the other hand, if you slowly, patiently wait for a following to form, and defer publication offers until you feel you have the upper hand, you may come up the winner.
(Of course, always keep in mind the MathWorld fiasco.)
I find on-line publishing much more satisfying than, say, vanity press. I write short fiction, which is pretty much an unpublishable genre today; but the Web lets me review and revise in an open-ended fashion, control the presentation aspects (not very well, admittedly), editorialize ad lib, etcetera. And it doesn't need more self-promotion than a well-landed link in Open Directory/Google and/or an affiliate link program. The latter can be even informal: find a site you like, convince them that they like your site, and swap links.
That's how the Web was supposed to work five years ago.
You should play his games, then. Zarf's narrative is immersive, evocative and depressing at the same time. "So Far" is a massive cathartic trip.
I really don't care much for the problem-solving side of IF (I don't enjoy playing games, I'd rather solve math problems:-), I wish he would write a novel some time, because I do believe he has The Gift(TM).
I quote in full, because the lack of understanding of this Box "guru" guy is appalling:
Another problem with HTTP [...] is that it is asymmetric. "Only one entity can initiate an exchange over HTTP, the other entity is passive, and can only respond. For peer-to-peer applications this is not really suitable," [...] programmers create hacks to get the limitations of the protocol [...] "It's all hackery, it's all ad-hoc and none of it is interoperable,".
Last things first, to clear the path: a blatant comission of the sin of conflation (a.k.a. bait-and-switch)! What does interoperability have to do with tomatoes? I guess it's a disclaimer for future incompatibilities ("hey, we already told you, HTTP is not interoperable").
Then, either I slept through all my classes on Networking, or the guy doesn't really know what he's talking about. You don't need to be Apache to be an HTTP server, the code to be a modest but fully HTTP/1.0 compliant server is not much more than the code needed to be a modest but fully HTTP/1.0 compliant client. So the issue of symmetry is more one of implementation than anything else. P2P is about roles (who's the initiator and who's the responder, as opposed to who's the client and who the server), not code (how do I write the initiating side and the responder side). Anyway, it's obvious that the code implementing the functions defining both roles will be different; otherwise, initiating wouldn't be any different from responding from the operational point of view and thus indistinguishable at any given moment. Let me stress this point: you have to be able to determine the direction of the flow at any given moment in time, even when talking about P2P protocols. It makes no sense to ask for a resource by sending it.
Among the problems with HTTP [...] is the fact that it is a Remote Procedure Call (RPC) protocol; something that one program [...] uses to request a service from another program located in another computer
HTTP is not an RPC protocol, it's a file transfer protocol (as a quick perusal of RFC 2616, Section 5 will show). Anything built on top of that will be, by definition, a hack. So why so much grief?
Indeed, you can type a GET request as application/x-rpc-call or anysuch, and pass parameters on the URI. But it's cheating, isn't it? So why is using HTTP as a P2P protocol "a hack"? This is a non-issue.
Lastly:
This works for small transactions asking for Web pages, but when Web services start running transactions that take some time to complete over the protocol, the model fails. "If it takes three minutes for a response, it is not really HTTP any more, [...] I need a way to send a request to a server and not the get result for five days."
Well, he's right on this count. But he doesn't know (or doesn't tell) why: as defined by the standard, HTTP is an application-level protocol. You can't build upon it, it's level-7, top of the stack, period. If you build upon it, you're breaking the ISO/OSI model. But aren't cookies a way to implement sessions on top of HTTP? Well, yes and no. Aren't cookies a hack? Of course. Why can't you use something like that to implement IOUs or tickets or return thunks or any other model for delayed responses? Because it would be a hack. Yes, but no more a hack than the eminently acceptable (and widely accepted) cookie hack. You can always reify state (including the result in a RPC); cookies just are a proxy for a lazily reified state.
I'm mystified (and angry) at the lack of understanding the article evidences.
I know other languages may be better suited for this task, but C++ does satify enough of the requirements. Could someone please explain why, a language should do its on Garbage Collection
Simply put, because even if the point of creation of an object is very clearly defined in the program text, the point of destruction is not, and can happen at any (and different!) point(s) of the program text. Hence, you need a very strict discipline (and sometimes, nontrivial analysis) to ensure that your resource checkbook balances nicely. GC is a huge help from the part of the runtime.
Don't, because it is (somewhat) true. You could think of it as a "really, really deferred garbage collection cycle":-)
But I wouldn't depend on atexit() handlers for resource reclaiming, as it might be circumvented (under conditions which I no longer remember), and it is not 100% portable (order of handler invocation, I think). What I use in C is simple exception handling with setjmp()/longjmp(), and judicious use of goto's "sugared" with macros to handle resource reclaiming. It is a kind of lean C++ minus the OO.
Yeah, so C++ doesn't have garbage collection, that means that you can actually use pointers without the risk of them disappearing.
If your pointers disappear on GC, either you don't play by the collector's rules, or your collector is severely broken. I've used Bohm's conservative collector in a smallish C++ program that used memory heavily (it parsed VB template definitions, built the syntax trees and wrote Java or somesuch) without problems: you don't have to do anything at all (it is drop-in by design), and it defines operator delete() as a no-op. It's somewhat magical, but it works.
"If the people who designed and wrote the software can't find the bugs, what makes you think that throwing somebody at it in their spare cycles is going to help? We want software that works, so we can do our business. Our business is not writing this software.
Well that sounds good, but it's been proven wrong in practice.
This may sound as a flame, but it's not. I am most definitely in disagreement with the hacker ethics. I believe that "hacker" is an euphemism for "lousy programmer". Most admit to not knowing what they are doing most of the time. Most brag about "proper indenting and commenting" of code to be the moral equivalent of wearing pink slippers and tutu in public. Many have no concept of personal hygiene, and so can't be expected to adhere to hygienic coding practices (strong typing, modularization...).
The divinization of the hacker ethics seems to me to be a distinctly American phenomenon, and I think it is probably the worst aspect of the American computing scene/marketplace/you name it.
Of course, some OSS is just great (to the top of my mind comes the *BSDs and almost anything by the Apache Project); but some OSS is just crap. This is of course a very general law (Sturgeon's Law, I believe), one that can't be expected to be circumvented by any amount of magic, not even by using Open Source processes and practices.
Pray tell me just how do you use it if you are left-handed?
So simple: design it so it's direction-neutral, add a pair of accelerometers to detect the direction in which you're holding it, and modify the display driver to swap the screen accordingly. Voilà! Plus, you have portrait- and landscape-mode for free.
Re:At least he's holding his convictions
on
The End of Cyber BS
·
· Score: 1
can't still change our lives
It has already transformed our lives in fundamental ways we don't even think about. They just seem "normal" now.
Also, the cutting edge shifts all the time. I tend to agree with Katz's grim outlook, being as I am online since '95 (in this backwater country called Argentina I believe time should be measured in dog-years, not man-years) and seeing the shift happen; but I think there are manifestations of vitality all over the Web.
You might argue that self-publishing (academic, fictional, biographical) and weblogs might be instances of masturbatory practices in general, but you could argue that of most of human endeavors and cultural productions. I think that there is where the real thing is with the Net, and it is as thriving and vital as ever. We speak, we converse with eachother, we meet, and, of course, we have sex, outside the chain of production.
You are not going to agree with me, but I invite you to think about this: by definition, doing things for fun is the exact opposite of doing things for business (Latin otium versus negotium, leisure vs. business, for the classicaly minded among you), and in the Graeco-Roman scale of values, business is something to endure only to obtain the means (material or otherwise) for engaging in creative leisure. As long as the Net keeps from turning from a playground into a marketplace, which I believe will never happen, it will be fueled with the output of our fun. And it will be good, very good.
Slashdot Mirror
Off the top of my head, I'd say lattice and group theory for designing error correcting codes. The Solomon-Reed ECC used in CDs and DVDs was designed from the structure of a special lattice.
A lot of "useless" theories (much more "concrete" than topology, though: Collatz bases, Cylindrical Algebraic Decomposition and whatnot) ended up in Computer Algebra Systems in very "useful" tasks as factoring polynomials and solving equations.
And, who knows, maybe the topological approach to Quantum Gravity does pan out in the end.
May I suggest using Ant? The <ftp/> task is handy, and @MACROS@ are tricky but serviceable.
Now, normally, being and essence are two seperate things
Only we Spanish-speakers know that. That's for having ser (to be) and estar (to be), y'know.
I think these 7 billion should be "accounted" as the savings O'Neill is making for American carpenters and plumbers by not lending any money to Argentina.
Not that I, personally, want any more IMF cookies in the Argentine cookie jar, but come on! Now I'm very tempted to say the word hypocrisy. But I will refrain from it.
Interesting. Use two nested loops, the outer iterating over differences from N-1 to 0 (that is, the N-1'th difference, then the N-2'th and so to the 0'th difference), the inner building the table of differences over the array.
It's O(N^gr(P)), where P is the polynomial to compute, and gr(P) is its degree. As it should be.
He was the Euclid of our times. Reading his writings I get the same feeling of economy, conciseness, clarity, effectivity that I do when reading the Elements. His calculational style of proof is, to me, entirely on par with Euclid's use of the Theory of Proporions.
I hope it won't have to take two thousand years before we recognize his fundamental brilliance.
FWIW, mirror at http://paginar.net/matias/shatter.html.
Could be. I thought Time was about the undying japanese woman and the crystal flowers...or is it the same book and the other one is about something else entirely?
Bah, my memory is like a sludgy swamp: everything in there decays to the same undifferenciated matter. The point is, I didn't like either book much, compared to Vacuum Diagrams. Don't get me wrong: both Manifolds are very good, very dark and depressing; but Vacuum Diagrams is more poetic, I guess is the word.
I gave up my hopes for science fiction a long time ago, anyway. It's all oh-so-marketable now. Seeing that Rowlands woman winning the Hugo last year was a sad sign-o'-the-times.
Stephen Baxter's novel Manifold: Space toys with the idea that the vacuum is at a metastable level. The book ends with the release of the vacuum to its actual ground state.
I finished it feeling profoundly depressed.
I do too...Just today I was watching an old (1992, I think) rerun of SNL...<sob>
Wives are evil.
Hmm...no, not for the American variety of Christians (what do you call them? Baptists?). Actually, the Catholic Church chose that path of reconciliation between doctrine and secular science, but by saying that the Bible must be read in a "poetic" light, or under a metaphoric interpretation. And that is precisely what American Christians reject: they believe the Bible is God's revealed, literal truth against which everything else is measured.
chances are the Virgin Mary wasn't a virgin either
She was a virgin! When she was called Aphrodite, she begot Pan on Hades and then bathed herself on the waters off Paphos and regained her virginity. Only that in Canaan she was called Mariam, her godly husband was Yahweh, or Baal (who also lived in a mountain of fire, as Exodus tells us) and his son was called Yeshu (who was a lamb, and died in Passover).
Mind your comparative mithology, please.
Done: here is the proof. Be warned, though: it's highly technical.
No, no, no, no! Please don't inflict upon yourself the pain of having to use AppleScript! Take a look at MPW instead.
Highlights: free (as in beer), integrated shell and text editor, handles very large files (4G), integrated C/C++/Asm for 68k and PPC, batch text editing, standard I/O support, "live" windows tied to the filesystem, Shell language for scripting, can send/receive AppleEvents...
Lowlights: Classic-only, discontinued by Apple.
Short answer: because not everybody is running X on Mac hardware.
Long answer: as much as I would like to use X, the sad truth is that MPW is far superior as a command-line shell than anything else on the known universe. In particular, I rely heavily on it for database development. Also, in my W&B G3 Classic feels much more responsive than X (I haven't tried 10.1 or later, though). MPW + Perl is like a dream environment.
Oh, I forgot: I still have to support legacy Classic applications (mostly, 4th Dimension externals), and I just can't compile and test them under X.
I think the key to Internet publishing is patience. If your work is a roar, you won't get a big exposure to it as fast as with a printed edition. On the other hand, if you slowly, patiently wait for a following to form, and defer publication offers until you feel you have the upper hand, you may come up the winner.
(Of course, always keep in mind the MathWorld fiasco.)
I find on-line publishing much more satisfying than, say, vanity press. I write short fiction, which is pretty much an unpublishable genre today; but the Web lets me review and revise in an open-ended fashion, control the presentation aspects (not very well, admittedly), editorialize ad lib, etcetera. And it doesn't need more self-promotion than a well-landed link in Open Directory/Google and/or an affiliate link program. The latter can be even informal: find a site you like, convince them that they like your site, and swap links.
That's how the Web was supposed to work five years ago.
You should play his games, then. Zarf's narrative is immersive, evocative and depressing at the same time. "So Far" is a massive cathartic trip.
I really don't care much for the problem-solving side of IF (I don't enjoy playing games, I'd rather solve math problems :-), I wish he would write a novel some time, because I do believe he has The Gift(TM).
I quote in full, because the lack of understanding of this Box "guru" guy is appalling:
Last things first, to clear the path: a blatant comission of the sin of conflation (a.k.a. bait-and-switch)! What does interoperability have to do with tomatoes? I guess it's a disclaimer for future incompatibilities ("hey, we already told you, HTTP is not interoperable").
Then, either I slept through all my classes on Networking, or the guy doesn't really know what he's talking about. You don't need to be Apache to be an HTTP server, the code to be a modest but fully HTTP/1.0 compliant server is not much more than the code needed to be a modest but fully HTTP/1.0 compliant client. So the issue of symmetry is more one of implementation than anything else. P2P is about roles (who's the initiator and who's the responder, as opposed to who's the client and who the server), not code (how do I write the initiating side and the responder side). Anyway, it's obvious that the code implementing the functions defining both roles will be different; otherwise, initiating wouldn't be any different from responding from the operational point of view and thus indistinguishable at any given moment. Let me stress this point: you have to be able to determine the direction of the flow at any given moment in time, even when talking about P2P protocols. It makes no sense to ask for a resource by sending it.
HTTP is not an RPC protocol, it's a file transfer protocol (as a quick perusal of RFC 2616, Section 5 will show). Anything built on top of that will be, by definition, a hack. So why so much grief?
Indeed, you can type a GET request as application/x-rpc-call or anysuch, and pass parameters on the URI. But it's cheating, isn't it? So why is using HTTP as a P2P protocol "a hack"? This is a non-issue.
Lastly:
Well, he's right on this count. But he doesn't know (or doesn't tell) why: as defined by the standard, HTTP is an application-level protocol. You can't build upon it, it's level-7, top of the stack, period. If you build upon it, you're breaking the ISO/OSI model. But aren't cookies a way to implement sessions on top of HTTP? Well, yes and no. Aren't cookies a hack? Of course. Why can't you use something like that to implement IOUs or tickets or return thunks or any other model for delayed responses? Because it would be a hack. Yes, but no more a hack than the eminently acceptable (and widely accepted) cookie hack. You can always reify state (including the result in a RPC); cookies just are a proxy for a lazily reified state.
I'm mystified (and angry) at the lack of understanding the article evidences.
Simply put, because even if the point of creation of an object is very clearly defined in the program text, the point of destruction is not, and can happen at any (and different!) point(s) of the program text. Hence, you need a very strict discipline (and sometimes, nontrivial analysis) to ensure that your resource checkbook balances nicely. GC is a huge help from the part of the runtime.
Don't, because it is (somewhat) true. You could think of it as a "really, really deferred garbage collection cycle" :-)
But I wouldn't depend on atexit() handlers for resource reclaiming, as it might be circumvented (under conditions which I no longer remember), and it is not 100% portable (order of handler invocation, I think). What I use in C is simple exception handling with setjmp()/longjmp(), and judicious use of goto's "sugared" with macros to handle resource reclaiming. It is a kind of lean C++ minus the OO.
If your pointers disappear on GC, either you don't play by the collector's rules, or your collector is severely broken. I've used Bohm's conservative collector in a smallish C++ program that used memory heavily (it parsed VB template definitions, built the syntax trees and wrote Java or somesuch) without problems: you don't have to do anything at all (it is drop-in by design), and it defines operator delete() as a no-op. It's somewhat magical, but it works.
This may sound as a flame, but it's not. I am most definitely in disagreement with the hacker ethics. I believe that "hacker" is an euphemism for "lousy programmer". Most admit to not knowing what they are doing most of the time. Most brag about "proper indenting and commenting" of code to be the moral equivalent of wearing pink slippers and tutu in public. Many have no concept of personal hygiene, and so can't be expected to adhere to hygienic coding practices (strong typing, modularization...).
The divinization of the hacker ethics seems to me to be a distinctly American phenomenon, and I think it is probably the worst aspect of the American computing scene/marketplace/you name it.
Of course, some OSS is just great (to the top of my mind comes the *BSDs and almost anything by the Apache Project); but some OSS is just crap. This is of course a very general law (Sturgeon's Law, I believe), one that can't be expected to be circumvented by any amount of magic, not even by using Open Source processes and practices.
I'd love to see in-depth books on Web programming using the Jakarta Project products, especially Turbine and Velocity.
They're extremefully cool projects, but severely lacking in documentation.
Pray tell me just how do you use it if you are left-handed?
So simple: design it so it's direction-neutral, add a pair of accelerometers to detect the direction in which you're holding it, and modify the display driver to swap the screen accordingly. Voilà! Plus, you have portrait- and landscape-mode for free.
There's no mercy for us lefties in this world...
--Matías
http://www.cs.utexas.edu/users/EWD/ewd09xx/EWD926. PDF
Also, the cutting edge shifts all the time. I tend to agree with Katz's grim outlook, being as I am online since '95 (in this backwater country called Argentina I believe time should be measured in dog-years, not man-years) and seeing the shift happen; but I think there are manifestations of vitality all over the Web.
You might argue that self-publishing (academic, fictional, biographical) and weblogs might be instances of masturbatory practices in general, but you could argue that of most of human endeavors and cultural productions. I think that there is where the real thing is with the Net, and it is as thriving and vital as ever. We speak, we converse with eachother, we meet, and, of course, we have sex, outside the chain of production.
You are not going to agree with me, but I invite you to think about this: by definition, doing things for fun is the exact opposite of doing things for business (Latin otium versus negotium, leisure vs. business, for the classicaly minded among you), and in the Graeco-Roman scale of values, business is something to endure only to obtain the means (material or otherwise) for engaging in creative leisure. As long as the Net keeps from turning from a playground into a marketplace, which I believe will never happen, it will be fueled with the output of our fun. And it will be good, very good.
Take a step back, look at it, see it happen.
Just don't despair yet.