Slashdot Mirror

WOW!! This wooden mirror is extra-special cool... I wonder what it makes for noise...

http://fargo.itp.tsoa.nyu.edu/~dan ny/mirror.html here are some more pictures and some quick time movies.. since the site linked in the article is getting slashdotted...

Sure, it looks cool, but imagine the same kind of device some thousands of times smaller. What do you have? A mechanical TV screen...

Using nanotechnology you could use this kind of mechanism to create screens of incredible resolution to whatever scale you wanted without any kind of distortion or loss of quality. If nanotechnology ever takes off, I reckon that this sort of screen will be one of the more useful applications. Want to turn every wall in your house into a screen? Sure, no problem :)

My favorite book is this one ( Amazon). Wide-ranging, great for both engineers and mathematicians, intuitive, rigorous, and clear.

Ken Perlin (of Perlin noise fame) has developed this technology called Quikwriting that seems to facilitate a one-handed interface better than anything I've seen. I know it's not a keyboard, and I know it's yet another code you'd have to learn how to use, but it appears to me to be the most efficient techonology in this neighborhood. While you're at his site, you should check out his other user interface considerations.

Ken Perlin (of Perlin noise fame) has developed this technology called Quikwriting that seems to facilitate a one-handed interface better than anything I've seen. I know it's not a keyboard, and I know it's yet another code you'd have to learn how to use, but it appears to me to be the most efficient techonology in this neighborhood. While you're at his site, you should check out his other user interface considerations.

It completely liberates interfaces from the rectilinear world of the physical displays that manufacturing technologies force on us. I've never seen anything quite so remarkable.

And, by the way, he's implemented the zooming interface lately entirely in Java. The presentation that I linked in above zooming user interfaces actually demonstrates the concepts live. Try it out. You'll never look at windows the same way again.

It completely liberates interfaces from the rectilinear world of the physical displays that manufacturing technologies force on us. I've never seen anything quite so remarkable.

And, by the way, he's implemented the zooming interface lately entirely in Java. The presentation that I linked in above zooming user interfaces actually demonstrates the concepts live. Try it out. You'll never look at windows the same way again.

Anyway, this "Eternity service" doesn't have anything like that. Here, Kobrin will say "Is there anything else that this data could have been?" and "Could these have been key shares to any other data?" Alice will have to say "No."

I believe you're missing the point. After reading the Publius paper, I have these points to offer:

• According to the paper, when a server receives its share of the key and data, "At this point, the server has no idea what it is hosting - it simply stores some random data." They are incapable, in fact, of determining what is on their server--they haven't the full crypto key.
• When a user wishes to retrieve some data, "In our implementation, all of the work is handled by the proxy." Handling this by proxy means that Helena is going to have a much harder time tracking down where the data is kept. If she does, the server will have no record of who publish the secrets, or even knowledge that the secrets were published! Perhaps it is possible to discover on which servers the disparate parts of the secrets are kept. If it is, Helena still will not be able to tell who originally published the secrets.
• Publius by itself does not provide any sort of connection based anonymity. This means that an adversary eavesdropping on the network segment between the publisher and the Publius servers could determine the publisher's identity. If a server hosting Publius Content keeps a log of all incoming network connections then an adversary can simply examine the log to determine the publisher's IP address. To protect a publisher from these sort of attacks a connection based anonymity tool such as Crowds should be used in conjunction with Publius. (taken from section 5.4 of the paper)
  So, Publius can't defend against that sort of attack, but assuming the publisher does indeed manage to get his data published anonymously, perhaps through the use of anonymizers (which is what Crowds is) or encryption like SSL, his anonymonity cannot be broken. That is the point of this system.

There's a lot more in this 14 page paper--it's very rich. It particular, it examines the attacks that an adversary could make against Publius and what safeguards could be put in place.

The most important thing, and I can't emphasize this enough, is that these guys have a system. This is not some theoretical, pie-in-the-sky wouldn't-it-be-nice dream, like the XOR business was. They have the details and mechanics of publishing, retrieval, and updating worked out. You may read the paper yourself if you don't believe me.

Unfortunately, I'm in no position to evaluate the strength of the crypto here. I would very much like to see someone with knowledge in this area come forward with an opinion after having read the paper.

Jonathan David Pearce

• Could the Publius Server Software completely fill my disk with Publius Content?
  Yes, the Publius Server could completely fill your disk with Publius Content. For this reason you may want to have Publius Content stored on its own partition or own disk. The Publius Server limits the size of individually published files to 100K.

Finally, this discussion comes to light without me having to ask it. I've been thinking about trying this for about 2 or 3 months, the problem I have is that my design seems rather novel, and I havn't seen any of the small boards/systems (like LART, TINI, TIQIT, uCLinux) that would support it hardware-wise, let alone getting the software working for it. Most of the following rant is nothing more than a pipe dream, but if you know of something to make this dream a reality, by God post it.

I envision a bifold device, about the size of a deck of cards, with rounded edges. The device flips open (either spring loaded to a set angle ala Psion, or with a friction clutch holding it at any angle), and both inside faces are LCDs with digitizers on them. The side that you hold in your hand is the input area,which can be changed to fit the application (for example, all buttons for a calculator app, or a few buttons with a writing area for a notepad app). The top half is the display area.

Two displays/digitizers may seem like a waste, but an infinitely configurable input area seems like it might be just the kind of thing to make this badboy very easy and fast to use. The other nice thing about two halves is that you get about twice the screen real estate, as well as a measure of screen protection. Additionally, the bottom half in the hand, with the top half above, allows you to write while resting your writing hand against the holding hand, which would make input more natural (i.e., just moving the wrist, as opposed to the whole arm I envision this system using Quikwriting as the primary input method, but implemetning other software would also be necessary, especially the stuff with the input area and receiving input. I could imagine that a writing area with four general buttons would be the default, and a special call would be executed to change this, that way, only programs that need to have a different input method would have it. Other programs could act as if they were receiveing input from a keyboard.

I already have the case design in my head (at least the design for individual manufacture). The problem I've run into is the lack of suitable hardware. Some of the devices listed above are small enough, but do not include any way (that I can see) of having a configurable input area that is separate from the display screen.

I am a Mechanical and Biomedical engineer by training, so most of the aspects of specialized hardware implementation are beyond me, and I have been looking into using pre-built boards and stuffing them into a novel case (which my training does let me specialize). So I ask you, fellow /.ers, "what do you think?" Am I a deranged loon, or does an idea like this have some merit (if not, I'll still want to build one for myself)? Can anyone offer me guidance for hardware and even some software? Anyone want to help build one?

--Copyright, 2000 by WhyCause (just in case something pans out)

Greengard and Rokhlin's Fast Multipole Method (FMM) algorithm computes an approximation for the sum total of the interactions between all pairs of elements out of a large group.

For instance, in astrophysics simulations, one quantity that needs to be computed is the total force on a star that results from the gravitational attraction from each of the other stars. If you have to do this computation for each star, then the total ammount of computation required grows as N^2, given N total stars.

This is where the name "The N-body Problem" comes from.

The FMM algorithm essentially models distant groups of particles (stars) as a single mathematical object and by using other fairly complex operations and representations, reduces the overall complexity from N^2 to N.

The importance of this algortihm comes from the fact that in many different types of scientific simulations (astrophysics, molecular modeling, computational fluid dynamics, etc.) the N-body computation was the limiting factor in the performace of these algorithms. Use of FMM and similar algortihms has reduced the overall simulation times by orders of magnitudes for large systems, allowing simulations that once required CPU-decades to be completed in CPU-months.

There are several good sources of FMM material on the web. You can try:

Mario's Nbody resources

More Nbody

Leslie Greengard's page

And of course, I'll have to plug our research group page at Duke

Hope this helps

-bill

Sic scribit timothy:

Book burning has been a hallmark of our century, although we certainly did not invent it.

If you haven't even seen Ada, here is a link to the GNAT compiler sources. Just download it, unzip and untar it and look at the code. Then let us hear what you think of it.

ftp://cs.nyu.edu/pub/gnat/gnat-3.12p- src.tar.gz

Having done my undergraduate CS at NYU, the 'N' in the Gnu Nyu Ada Translator (GNAT - how many people knew that), and having studied under two of the developers of that system (their company's site) I was fortunate enough to be exposed to virtues of this language.

The Ada syntax is very similar to Pascal's, but the language is very similar to Java (especially thread support). Once you get accustomed to using the language, you notice that you can be very, very productive using it, much more than in C++. I would also say that the learning curve (minus the time to familiarize yourself with the syntax if you are coming from the C/C++ world) is pretty easy to climb, and you can be proficient at it soon.

For my compiler class, we needed to write a compiler for a (the non OO) subset of Ada95. I chose to write mine in Ada95, because we were allowed to use the GNAT lexer/parser (which was written in A95 as well). I would strongly recommend that anyone wanting to learn large scale programming or who is developing something that will be open source, should take a look at the source code. It is clearly written, well documented, easily understood, and even beautiful. It is a wonderful example of how someone should write code if the expect others to read it. It also shows just how beautiful and understandable the language is.

I'd really like to see a PDA with Quickwriting from Ken Perlin.

Check the Java demo of how it works here.

Also, check this picture of an addon to Palm VII!

Damn cool!

--
GroundAndPound.com News and info for martial artists of all styles.

I'd really like to see a PDA with Quickwriting from Ken Perlin.

Check the Java demo of how it works here.

Also, check this picture of an addon to Palm VII!

Damn cool!

--
GroundAndPound.com News and info for martial artists of all styles.

I'd really like to see a PDA with Quickwriting from Ken Perlin.

Check the Java demo of how it works here.

Also, check this picture of an addon to Palm VII!

Damn cool!

--
GroundAndPound.com News and info for martial artists of all styles.

This new 'graffiti' from NYU is done by Ken Perlin (fron Perlin Noise fame) and it's absolutely fabulous. It's called Quikqriting. Can't wait to use it. Check it here: http://www.mrl.nyu.edu/perlin/ demos/quikwriting.html

--
GroundAndPound.com News and info for martial artists of all styles.

I wonder if Litman's talk on 'piracy' was adequately reported.

Recently at another conference, she spoke in favor of changing the rhetoric in these debates. I suspect her talk this time was an attempt to do that. In other words, we have to invent better ways of describing our good activities, instead of reusing the words of the enemy. And 'piracy' is exactly the word that Jack Valenti of the MPAA uses to describe us. (It's like the 'hacker' vs. 'cracker' rhetoric, only more extensive.)

Peggy Radin of Stanford used this expression, "You can't use the master's tools to take apart the master's house." (from feminist theory). Read more on that conference at NYU March 31 to April 1 at http://www.law.nyu.edu/ili/conferences (and check back later for the webcast archives and transcripts). Roger Clarke might wish to update his notes too.

---

gmp

"Business Models for Open Source Hardware"

---

gmp

Frankly this really sounds like one of those meaningless deconstructionist philosophy rants. The ideas presented appear to be self-consistent but have no bearing on the real world, unless your sense of self is so far gone that the real world is too difficult for you to comprehend and you must make up a fantasy-world that works according to your own rules.

This actually reminds of the stir that Alan Sokal created a few years ago by submitting a phony paper to Social Text, and blew the lid off some of the really idiotic (and totally irrelavent) ideas coming out of a certain school of philosophy. The editors and they're supposedly intelligent insights had become so disconnected from reality that when someone (Sokal) came along and suggested that the real world doesn't really exist, they fell for it, hook, line, and sinker...

If you're looking for a portable language that compiles to native machine code and which implements much of Java's semantics, check out Ada 95. You can find information here, or download a complete GPL'ed compiler here.

I'm totally serious, folks. Do not regale me with tales of how much Ada sucks--most originate from introductory CS classes where Ada83 was shoved down unwilling throats by indifferent or hostile educators. Please, go read and experience for yourself before replying. And for those who dispute my claim about Java semantics, please pay special attention to the links on this page before you comment.

I haven't checked it out yet, but seeing these posts made me think of it.

- AC

... except on a popular culture outlet rather than on academia.

(For those who don't know, Alan Sokal is the professor who managed to get an article arguing that gravity is an arbitrary social construct accepted to a peer-reviewed journal, and promptly revealed that he had written it to see if they really would publish such a piece of obvious nonsense. The Editors Were Not Amused.)

"Television is the first truly democratic culture -- the first culture available to everybody and entirely governed by what the people want. The most terrifying thing is what people do want."
-- Clive Barnes

For those of you who think this is impossible because of the variations between languages, Noam Chomsky has something to say to you. I was exposed to his idea back in formal languages and automata class. Basically, his argument is that we have universal grammar (UG) parser built within us when we are born. We 'hardened' the parameters to the UG to conform to our prefered language. Sorta of like guile and perl where guile is a very expressive language but perl, while express less, can express the same thing in a more consise manner.

Universal grammar is defined by Chomsky as ``the system of principles, conditions, and rules that are elements or properties of all human languages... the essence of human language'' [Chomsky, 1978].

Thus, all languages that we are accustomed, English, Arabic, Malay, Japanese, and Chinese are special cases of a universal grammar. Chomsky and subsequent linguists are looking for those common elements of all languages.

Universal grammar and the innateness hypothesis

Universal Grammar in Prolog

There are lots of discussion about this... see google.

Hasdi

In the novel people weren't genetically engineered, but stunted with salt water solutions while being incubated before birth. This caused some to develop as "Stupid" -- to work in the lower class of jobs and be content with it.

http://www.mrl.nyu.edu/perlin/ demos/quikwriting.html

For those interested in the whole affair, look up the paper's title in Altavista. Here's some of Sokal's commentary on the spoof.

For those interested in the whole affair, look up the paper's title in Altavista. Here's some of Sokal's commentary on the spoof.

Something like this already exists. Look at Javelin and Charlotte

It looks like you can get it here I'm not doing to well with this java demo though :(

There is proof that bad writing is encouraged in academia. All you have to do is go read about the Social Text Affair.

People can write post-modern-sounding gibberish and it will get published, quite possibly in a rigorously reviewed and respected academic journal.

Good writing is clear, concise, and to the point. I agree with you on that. The problem is that our institutions of higher education don't teach people this.

- deb

The link above (excerpting net.wars?) attributes this notion to the alt.culture.usenet FAQ.

- rod

The Media Research Lab at NYU is doing research on something even cooler: autostereo, or 3D without glasses. AFAIK they haven't built anything yet, but a pretty cool applet demonstrating the concept is at the following URL:

http://mrl.nyu.edu/perlin/demos/aut ostereo.html

~k.lee

Unfortunely the article didn't give a link to Electronic Disturbance Theater, so I will give one http://www.nyu.edu/projects/wray/CHRON. html - This give a record of previous EDT actions including the one mentioned in the article. The incident was not really a hacker attack, it was a coordinated effort by people around the world basically reloading the web pages of the Pentagon, Mexican President Zedillo and the Frankfurt Stock exchange not as a means to do harm, but to publicize and display their displeasure about the situation with the Zapatistas in Chiapas, Mexico. YA BASTA!