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Michael Spivak is writing Physics for Mathematicians, of which the beginning can be downloaded. Videos of the lectures are supposed to be available, but I couldn't get them to load. Has anyone heard recent news of this book?

Many of the standard introductory undergraduate and graduate physics textbooks have been mentioned by other posters, but I'm surprised that no one has mentioned Michael Spivak's Elementary Mechanics from a Mathematician's Viewpoint , which is based on his Pathway Lectures at Keio University.

Michael Spivak is a mathematician who wrote the very popular math textbook, Calculus on Manifolds, which you've probably used in a class. Apparently he has given some video lectures on elementary mechanics. I haven't watched them, but he's an excellent teacher so they are probably great.

http://www.math.hc.keio.ac.jp/coe/videos/spivak2004/

Similar devices are already being used to give paralyzed people the ability to walk around and explore virtual worlds. For example recently Japanese scientists from Keio University demoed a product that lets a physically handicapped user interact with a virtual world like Second Life.

This is part of Keio University and Dentsu's joint venture into Secondlife, UI, interaction and social study.

There is some practical value. For example, several random number generators have periods that are exactly (or some function of) Mersenne primes. The aptly named "Mersenne Twister" is perhaps the most common these days, and if you need a good random number generator for some non-cryptographc reason (maybe a game or a scientific simulation) then you should take a look at it here

Now, the RNG you can download there has period 2^19937 (a Mersenne prime), but every time someone discovers a bigger Mersenne prime, we can construct a new Mersenne Twister that'll take even longer before it starts repeating itself.

FWIW, Mersenne Twister is not the only random number generator to require Mersenne primes. Compagner has another good one, and there are a few others...

Aww, come on, at that point you might as well mention Al Gore...

There were browsers before Mosaic; only they were text-only. The transition between text-based applications and GUI-based ones is trivial and well-documented; it happened at NCSA, but it might as well have happened in New Zealand, or Germany. At the point Mosaic was created, there were already quite a few sites on the Web, or it would have been useless for Kunz et alii to build a graphical client for it -- there was a rival protocol, Gopher, developed in the US, but it was more complex and seems to have all but died out.

Finally, know that the W3C, which regulates the Web, has its copyright held jointly by three bodies: One is MIT in the US, another is the European ERCIM, and the other is Keio U in Japan. Pretty international, if you ask me.

This electic car (previously mentioned on ./ ) has 8(!) electic motor in wheel thingies - much cooler!

A Mersenne Twister is just a fancy name {probably made up by some marketing type}

Just as additional info... http://www.math.keio.ac.jp/~matumoto/ename.html

It's too bad that, outside of a few people in the scientific community (such as those running Monte Carlo simulations and statistical thermodynamics calculations), no one uses random number generators (RNGs).

And the worst thing is, the aforementioned people who do use RNGs undoubtedly will want to run their own generator that is most likely superior.

For example, I run Monte Carlo simulations of polymer networks. The algorithm I use is the Mersenne Twister algorithm, which has an enormous period of 2^19937 - 1. This is much superior to VIA's built in RNG, and much faster than the standard rand() function in C.

So I'm sorry, but I fail to see the utility of VIA's RNG. It's a cool little toy, and I'm sure it's going to get VIA some publicity, but I'm betting that it will be a hard sell to most people.

It's...a bit of a tribute. Some of the best code I've ever seen -- brilliant, mind-bogglingly cool stuff -- comes out of Japan.

OK, so maybe it's a bit of an ego trip to lump myself in with these guys...but it's Open Source, BSD stuff; if I was getting paid to write it I'd probably have to name it something like "NetXPress Pro Enterprise Edition". Since it's free, I get to call it whatever I like :-)

What code impresses me? Off the top of my head:


Gogo, world's fastest MP3 encoder.

PVNation. You really want to hear the output of Shapee.

So, that's the story.

--Dan

It's...a bit of a tribute. Some of the best code I've ever seen -- brilliant, mind-bogglingly cool stuff -- comes out of Japan.

OK, so maybe it's a bit of an ego trip to lump myself in with these guys...but it's Open Source, BSD stuff; if I was getting paid to write it I'd probably have to name it something like "NetXPress Pro Enterprise Edition". Since it's free, I get to call it whatever I like :-)

What code impresses me? Off the top of my head:


Gogo, world's fastest MP3 encoder.

PVNation. You really want to hear the output of Shapee.

So, that's the story.

--Dan

One of the images indicates that the 2980kg weight includes eight passengers. Assuming 80kg per passenger, that's 640kg right there, leaving 2340kg. Two and a half metric tons isn't so bad for an eight-passenger vehicle.

check out the 3rd or 4th picture on this page. add a TV, ps2, and a mini-fridge and it's a quick, comfy miami to seattle trip :-)

Because it's not in the KAZ article itself, pictures of the car are available here:

http://web.sfc.keio.ac.jp/~hiros/kaz/pict.html

• Far longer period and far higher order of equidistribution than any other implemented generators. (It is proved that the period is 2^19937-1, and 623-dimensional equidistribution property is assured.)
  
• Fast generation. (Although it depends on the system, it is reported that MT is sometimes faster than the standard ANSI-C library in a system with pipeline and cache memory.)
  
• Efficient use of the memory. (The implemented C-code mt19937.c consumes only 624 words of working area.)
  

The versions of rand() and srand() in the Linux C Library
use the same random number generator as random() and sran
dom(), so the lower-order bits should be as random as the
higher-order bits. However, on older rand() implementa
tions, the lower-order bits are much less random than the
higher-order bits.

Know the iterating function and the last result to the precision it is stored in the iterating function- know the next number in the sequence.

This can be very hard to determine. Here is a random number generator with period 2^19937-1. Presumably it could be modified to support a larger period.

Surely with a Nelson box, Fox would be aware exactly how much you'd been watching the show, because of the micropayment system built into your TV :)

Just curious why everyone is referring to Xerox in the posts about this story.

Engelbart was at SRI. I'm pretty sure Ted Nelson wasn't at Xerox either - he's at Keio University now. And Vannevar Bush was way before PARC's time.

Anyway, just curious.

Ted Nelson coined the words hypertext and hypermedia in 1963.

His self-published books are required reading for anyone interested in hypertext, copyright, publishing, and what happens when you don't wanna compromise.

The desktop metaphor isn't dead. Anyone who tells you this should be taken out back and shot, to put it bluntly. What IS dead, however, are non-ergonomic, clumsy, single-workspace, non-intuitive desktops that disallow fast expression of a user's wishes. Like Windows. Like the OSX. Like Gnome. Like KDE.

This article would have been better suited to bashing "unnatural storage heirarchies" that the typical Joe User puts up with on a daily basis, instead of trying to drive another nail into the Desktop coffin. The reality of it is, it never began this way. Heirarchical storage management never hit the mainstream until the early 90's, despite having been around for at least 20 years by that point (re: Doug Englebart, his NLS "here's a mouse" demo in SF '68..it discusses other ideas besides using a mouse, like heirarchical storage)

Most systems prior to Windows, including Desqview, GEOS, and even the lowly Atari ST's GEM desktop were non-heirarchical. They were also far easier to use for people who didn't want to have a degree in computer science in order to use their computers effectively. It was only in the mid 80's that "heirarchical storage"-based desktops began to appear on mainstream computers ala AmigaDOS, MacOS, etc.

Anyway, enough history. I propose a solution. There needs to be a new GUI project started which is willing to accept, employ, and demonstrate new, unorthodox ideas. Lets just see what works. Lets try new ideas and see if people like them. If it floats, it stays. If it sinks it sucks--Simple as that. You cant call the desktop metaphor dead until you *try* to you've exhausted every thread of discovery, and tried everything there is to try, and thats clearly not whats happening these days. Gnome and KDE, are in their own niches now, neither project is willing to change horses in midstream and overhaul the appearance and function of their respective systems. There needs to be a third entity. I tried, back in '97 with InSight. Some of the ideas we developed during numerous late night brainstorming sessions were good enough to get published, and utimately earn a citation from ACM. Its not that hard, guys. You just have to recognize what you use because you're stuck with it, and what you use because it makes sense. Document-centric desktops, for example. Do you really need a document-centric desktop? Wouldn't it be more condusive to have a xanalogically oriented desktop? Why is the web 1-dimensional? Wouldn't it be better if HTML was a parallel data structure you could use to "drill down" to the original source of the information you're reading instead of wandering down a one-way street? Why do you use scrollbars? Do you use them because they're the only thing you know about? Do you recognize how clumsy they are, how counter-intuitive they are to use, and how much real-estate they waste? Can you think of how to implement scrolling in a different, better way?

Well, I have. Infact, i'm working with a guy named Johnathan Walther (and have been for the past month and a half) on designing a demo for such a device. Thats right, we have something we feel will finally deliver a death blow to scrollbars. We already have a working model, which is undergoing the final stages of fine-tuning prior to release. We'll be co-authoring a whitepaper for publication on how to build it, and how to implement it. The code will be meticulously documented, and we're going to throw it at anyone willing to see it. Hopefully, /. will run the story, and you'll still be interested enough to see what we've been building damn near every day for the past 8 weeks.

So, what are you doing to make things better?


Cheers,

This whole sorry saga remains so ridiculous. What does BT possibly hope to gain from this? The patent is so incredibly vague, and obviously closely related to so many other vague computer concepts both before and after the patent, as to be, IMO, not worth anyone's time or money.

Others have mentioned Englebart (the father of modern software concepts in so many ways) and Ted Nelson, who really started the whole hypertext thing rolling in the late sixties. And anyone writing about hypertext has to acknowledge the grandfather hypertext system, Vannevar Bush's "memex".

How that stuff holds up in court against this particular patent, I don't know.

But in the grand scheme of things, it's stupid.

I guess they just hope to get a few thousand bucks out of Prodigy in court? If thats they're only aim (and it seems like it is), it's pathetic. My esteem of the corporate tech world has sunk to incredible new lows!

If the web browser was patented, we'd have had to wait 17 years after 1960 for Ted Nelson's patent to expire. As that's only 1977, and the first commercial microcomputer had appeared only two years earlier, we'd not have had browsers in our homes immediately. And if we waited for Ted...well, we're still waiting for transpublishing and Project Xanadu to become popular. It took several more years for reasonable graphics to show up and make graphical web browsing practical. Commodore's Amiga and others had reasonable graphics, but it wasn't until VGA came out that graphics on most personal computers began to approach TV resolutions.

If the web browser was patented, we'd have had to wait 17 years after 1960 for Ted Nelson's patent to expire. As that's only 1977, and the first commercial microcomputer had appeared only two years earlier, we'd not have had browsers in our homes immediately. And if we waited for Ted...well, we're still waiting for transpublishing and Project Xanadu to become popular. It took several more years for reasonable graphics to show up and make graphical web browsing practical. Commodore's Amiga and others had reasonable graphics, but it wasn't until VGA came out that graphics on most personal computers began to approach TV resolutions.

Everything is a good example of a well-connected, deep collection of linked documents. However, Everything does not much in the way of structure, nor is it easy to compare documents or change how the structure is seen. An encyclopedia for today's world, additionally, would really demand graphics and video for some of the concepts. Certainly animals should be shown, not described. (Nelson's hypertext is much closer to hypermedia in today's parlance. Since Nelson invented the term hypertext, the change is due to misuse of the term.)

However, Xanadu has never been implemented fully. So, instead, the project may have to work through some sort of versioned, checked HTML (to verify links), and provide some powerful tools to search and manage the data.

Although I don't usually find bibles terribly exciting, this thing's a real work of art. Pity they don't make books like that these days.

Incidentally, there is another one (from the University of Keio (Japan) here.

I wouldn't say it's a 'great' history, as it casts Nelson as an out and out eccentric with a drive to an Augean task which has been fraught with more disaster than Apple, which Nelson has refuted himself. Check out this link for a better view, or dig through the Xanadu project site or Ted Nelson's homepage.

There's this clique of "digerati" who keep popping up on its pages and in similar forums/magazines/books, explaining the future in all its robotic nanotech cybernetic glory. The same names keep appearing over and over, repeating visions of a future so vague and full of popcorn sci-fi visions that you can't quite pin down anything specific, but can debate about it for weeks.

You may have seen these names before, waving hands and talking about the amazing future - Nicholas Negroponte, Marc Andreesen (even makes the cover of wired recently, all for having co-written mosaic w/ eric bina), Lanier, Kurzweil, Ted Nelson, Gelertner, etc. Most or all of these have been "has beens", who never quite produce anything useful, except visions of the future that are lapped up by journalists and viewed as the gospel.

But the real reason I'm writing is that you've thrown "Ted Nelson" into the list of people who are (a) trumpeted by Wired and (b) have never done anything useful. For one thing, Wired is if anything hostile to Ted Nelson, and for another thing, whatever Nelson's failings as a coder or a manager of coder's he *did* suceed in writing some fairly influential books. You may not have read any of them, but Tim Berners-Lee has. The web might be a better place if more people understood what Nelson was after with Xanadu: here's a new Nelson paper on the subject.

I'm as annoyed with Wired-style fluff as anyone (take a look at the New York Times "Technology News" headlines: it's all about who-bought-who this week. Technology?). But there is no simple rule-of-thumb to find brilliant writing. You can't just refuse to read anything by someone who's not rated a Master at advogatro. Is there any reason to care about, say, Linus Torvald's opinions about, say, globalization, compared to some nameless writer at the Economist?

And just to see if we can start a little trend here and actually talk about the article: Jaron Lanier is not at all sounding like the re-incarnation of Hugo Gernsback here. Is there any reason at all you attached this rant to this article, except that you've heard Jaron Lanier's name in Wired magazine?

Enhancements would be like AI or finding a better random # generator (check out this one if you care about that sort of thing).
DVDs are an area that is actually quite outside of CS and more in the realm of hardware engineering.
I know my ideas are not terribly popular but it's a social issue. And ultimately a social issue that has money tied up with it.
And also to be quite frank I can't afford a DVD player and the only one I might get would be in the form of a Playstation 2.
Also I can't even figure out how someone can crack an encryption scheme in the first place. I have at least minimal calculus experience and I can't even decipher some of the ideas about encryption and the like. It's an academic excercise that is best left up to people who actually will explain it better for people like me.
Ultimately since companies are composed of people there are limits to power. Governments have power companies have limits on their power. If push came to shove companies have to bow to unkie sam.

Energy moves in waves. Our biosphere is sustained by the cycling energy of daily rotations and seasonal shifts. Each member of the food chain reciprocates what it gets with what it gives. But what is given back in free beer software?

The credo of those opposing Free or Open Source software movements is usually TANSTAAFL. As mentioned in this article, software from a business can be free to some (such as non-profits) while its net pricetag is subsidized by others. Yet, the GNU project and the standards of Internet weren't built by businesses as much as they were built by individuals, each taking the personal cost of contributing. (For instance, HTML was largely inspired by Ted Nelson's early quest for Xanadu.) Some are paid back in microcelebrity or even better jobs and grants. Others have given unconditionally without reward. These pioneers made the effort, not so much for money, as for the personal empowerment of software.

Love really does make the world go around: The thing that best guarantees success is for human attention and concern to be lavished skillfully on a goal. Sometimes it seems that corporations will totally rule the world... until the court of public opinion turns the tide against them. These are like yin and yang cycling over one another: Propriety-mindedness and control versus personal liberty.

We're seeing a turn of this cycle happen when businesses turn to businesses (B2B) in a trend away from catering to consumers (B2C). Consumer backlash sometimes sparks this trend. Still, consumers have little use for computers without personal empowerment, so they will empower their own. (C2C?)

Free Beer Software will flourish just out of the human attention it gets. One day, the wireless web will be so pervasive that we can call out URLs like incantations, summoning any manner of program to be carried out. Such a post-scarcity world will be glorious!

this technology allows traditional media (okay, forget about the imperfectness of the system for a moment) to become part of the docuverse. this allows for Nelson's concept of "transclusion" to happen. Basically, transclusion is a way for the integrity of original materials to be maintained. for instance, quotes can often be taken out of context in a journalistic article. transclusion would allow the quote to be linked to the full text. okay, that may not sound so amazing, but for an information junkie like me, it's useful.

there's another important aspect of transclusion Nelson talks about that some other posters touched on - automated royalty payments. if you follow a link, a centralized system can track you and automatically charge you (or the author of the article) for use of their original material.

transclusion
ted nelson

To say "We've written the system in XML." is about the equivalent of saying "We've written the system in ASCII and matched the parentheses."

In the vast majority of applications, when people say "XML" they really mean something like RDF, BRML, RELML, etc.

The best use of XML currently is to simply dump existing relational databases to the web and index them with XML-oriented search engines like XSearch for things like RELML.

One of the pit-falls of "XML-oriented search engines" is that they fail to provide basic query capabilities such as numeric comparison on the indexed fields. This is really unnecessary since all they need to do is put the XML data back into a relational database on their end and index appropriately on the numberic fields. If they don't like the schema checking, they can always use LDAP and turn off schema checking.

An example of good use of XML via RELML is at www.nmre.net. Check it out.

Beyond this simple "dump the legacy rows to web pages" approach to E-commerce searching, there are the inferential systems that are more or less the equivalent of inferential databases. In these schemes, rather than storing literal values for the database rows in XML fields, a set of rules of derivation are included along with the XML data fields, and the actually index values that are not explicitly specified are derived prior to indexing. One might think of these as methods derived attributes as opposed to stored attributes. This is the direction Guha et all were trying to take things with RDF, but IMHO, failed to find the "sweet spot" of simplicity and power required for a new standard.

The dog uses the Aperios real-time operating system. More information is available on the Sony site.

I thought it was particularly interesting that it is IPv6 ready. Not many people can claim that for their pets! :-)

From one of Ted's papers: "The currently popular model of SGML (and its derivatives HTML, XML) scrambles together two intrinsically different kinds of data which are intrinsically parallel. "

The idea here seems to be that the text is one kind of data, and the markup is another. This is valid for HTML. What he doesn't seem to get is that the data contained within XML tags is lots of different kinds of data, with the data type defined by the tags. It would be nonsensical to separate out these tags into a parallel stream as he describes, so that we can apply different tags to the bytestream.

It makes sense if you're thinking of text-related tags like "paragraph" or "subhead." But if you have tags like "price" or "creation date," tags that denote meaning instead of just organization, it's better to have those tags firmly fixed in place. Swapping tags around would be like doing random typecasts.

hard to explain but it's pretty damn cool (and runs on linux):
http://www.sfc.keio.ac.jp/~ted/zi gzag/xybrap.html

Ted Nelson explains the key concepts of Xanalogical Media elegantly in this article but has some conflicting things to say about centralization and copyright issues. He states that service providers would have to guarentee the future publishing of material and that material would have to be pulled down from the recognised publisher. This will allow the automatic paying of copyright fees etc.. This is very different to the decentralized WWW that we all feel confortable with. On the Xanadu Net you can quite quickly supress your latested publishing should you decide you said the wrong thing, just remove it from your ISP (and sue them if they refuse).. does Ted value the "once it's up it's cached and copied forever" mentality of the web? If so, Xandadu should be a distrobuted system which encourages the free and total exchange of ideas. There's no need to pay an upfront fee to guarentee that your work will remain available for people to cross reference, if it is valued then it will be read and cached more frequently than those articles which are sparingly used as reference. It would indeed be a task to construct a distrobuted data store that we all can poke into efficently and publish what we want into.. was this not what Xandadu was originally intended to become?