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Who designed the Tacoma Narrows bridge? The Kansas City Hyatt Regency Hotel walkway? The De Havilland Comet 1? The Ocean Ranger oil rig? The L'Ambiance Plaza in Bridgeport, Connecticut? Pre-Challenger solid rocket boosters? Hubble space telescope optics? The Cypress Structure (collapsed in 1989 Loma Prieta eauthquake)?

I knew I should have put a caveat in there

Ok 99.99999% reliable. In most of the cases you mention the reason for failure was encountering a novel method of failure, that hadn't been seen before which is quite rightly the engineers fault for not anticipating it or basic human error which will happen in any situation, but should still be designed against by the good engineer.

Tacoma Narrows bridge - One of first examples of resonance in a large structure caused by wind. Regency hotel Walkway - Predominantly human error in communication coupled with a poor engineering decision Ocean Ranger rig - Engineering design coupled with human incompetance and poor safety routines. DeHavilland Comet- New intensity of cyclic stress strain loading in 1st commercial jet plane.L'ambiance Plaza Generally poor design in a (fairly) new technique.Rocket boostersDesign and checking failure on a massively complex project, obviously pushing the boundries. Hubble optics Not realy in the same catagory, but poor checking procedure, again pushing the envelope.Cypress StructureOver zealous engineers working to code, in an environment they didn't realy understand. Also a relatively novel construction when built.

I know it's not an excuse to say 'we didn't know it worked like that we'll do it better next time'. Compared to the number of structures built the number of failures is very small, engineers have a high level of training to keep it that way. It's a shame that (in the UK at least) we tend to sell our services cheap which doesn't reflect on the importance and responcibilty that we have. When individual code monkeys can get sued for the money a company lost due to there poor code, then they'll make themselves into engineers.

...that doesn't contain uneccessary and often confusing references to obsolete virgins I know little (and care less) about.

You mean like, Little Women?

Corrected link for the Why does the universe have 3 spatial and 1 time dimension? paper.

I would be interested in reading something of the level of Scientific American on this elsewhere on the web.

The article made it seem like this idea is far from proven. If it IS so wacky then why such attention paid to it?

a very cool diagram of "Relationships between various basic mathematical structures" from his Theory of Everything paper

and another paper addressing the question: Why does the universe have 3 spatial and 1 time dimension?

--LP

a very cool diagram of "Relationships between various basic mathematical structures" from his Theory of Everything paper

and another paper addressing the question: Why does the universe have 3 spatial and 1 time dimension?

--LP

a very cool diagram of "Relationships between various basic mathematical structures" from his Theory of Everything paper

and another paper addressing the question: Why does the universe have 3 spatial and 1 time dimension?

--LP

a very cool diagram of "Relationships between various basic mathematical structures" from his Theory of Everything paper

and another paper addressing the question: Why does the universe have 3 spatial and 1 time dimension?

--LP

a very cool diagram of "Relationships between various basic mathematical structures" from his Theory of Everything paper

and another paper addressing the question: Why does the universe have 3 spatial and 1 time dimension?

--LP

a very cool diagram of "Relationships between various basic mathematical structures" from his Theory of Everything paper

and another paper addressing the question: Why does the universe have 3 spatial and 1 time dimension?

--LP

a very cool diagram of "Relationships between various basic mathematical structures" from his Theory of Everything paper

and another paper addressing the question: Why does the universe have 3 spatial and 1 time dimension?

--LP

a very cool diagram of "Relationships between various basic mathematical structures" from his Theory of Everything paper

and another paper addressing the question: Why does the universe have 3 spatial and 1 time dimension?

--LP

a very cool diagram of "Relationships between various basic mathematical structures" from his Theory of Everything paper

and another paper addressing the question: Why does the universe have 3 spatial and 1 time dimension?

--LP

a very cool diagram of "Relationships between various basic mathematical structures" from his Theory of Everything paper

and another paper addressing the question: Why does the universe have 3 spatial and 1 time dimension?

--LP

Reminds me of G. K. Chesterton's short story "The Singular Speculation of the House-Agent" from "The Club of Queer Trades". A character (Lieutenant Drummond Keith) is involved in a scuffle and disappears. He has left his address as "The Elms, Buxton Common, near Purley, Surrey", but when some aquaintances go to look, there is no house of that name. The hero of the series, Basil Grant, then goes along and finds him in a tree-house in an Elm tree on Buxton Common. He then has the great line:

"The second [thing] is to remember that very plain literal fact always seems fantastic. If Keith had taken a little brick box of a house in Clapham with nothing but railings in front of it and had written 'The Elms' over it, you wouldn't have thought there was anything fantastic about that. Simply because it was a great blaring, swaggering lie you would have believed it.'

Project Gutenburg has the book

Either they're elegant, or you're trapped in a misconception :)

Ofcourse you can view C and Unix as great tools that worked wonderfully over the years.. Or you can blame K and R for an insecure design (yielding problems such as The Confused Deputy) and the general insecurity problems that exist in Unix and C and not in many alternatives.

The concept of a process is also not very related to Unix specifically, but found everywhere where hardware-level separation between threads of execution is useful. I think in the future, such protection will be achieved at the language-level, rather than the hardware level, and that processes are actually ad-hoc and not in any way elegant.

As for files... I see those as the general concept of applications explcitly serializing and persisting their data into bit streams uniquely identified on the disk via string hierarchies. I don't find that elegant at all. In fact, I find Orthogonal persistence a lot more elegant.

I believe Unix encapsulates some nice creative ideas, even elegant. But I also think that the positive concensus about them is a simple reflection of the poor alternatives and of general ignorance of better and more elegant designs out there.

It's also on Project Gutenberg. link

Interesting... I started looking, and I found Citation analysis of pathology journals reveals need for a journal of applied virology!. It's from 1973 and the first paragraph seems to describe PageRank exactly (except in terms of scientific journals instead of web pages), and the way it's stated, it seems to be a reference to a system which was already widely used. Sounds like Google reinvented the wheel...

BTW: I recommend Unison to sync.

For me it's background color ( who at MS thought that "teal vomit" was an attractive color?)

Yes! That shade of teal was horrible :-( I believe the reason that shade was chosen was that it was the best they could come up with from Windows' 20 reserved colors -- teal ("#008080") is one of them (although I wish they had chosen chosen navy ("#000080") or maroon, or even black).

At least Windows 2000 had a better shade of blue as the default ("#3a6ea5"), and Windows XP was the first version of Windows with a wallpaper on by default (it was also the first version of Windows to require at least 16bit-color in its default configuration).

Who is this John Q Student and why must he issue "Enforce In-Order Execution of I/O" instructions so often?

It's a shame that Kirby's Adventure came out so late in the life cycle of the NES, but this one is about as good as it can get in a 2D platformer. I won't argue whether it's better than SMB3 or not because they're both great. Shameless plug for my NES Contra site here.

I stumbled accross this book on Project Gutenberg: Heroes of the Telegraph by John Munro. It's a fascinating account of the various inventions that led up to the telegraph. Oddly enough, the book was written when the telephone and phonograph were pretty new, so the author's speculations as to the future of these devices is interesting.

Bandwidth isn't such a big issue in my experience. I have a modem connection at home, but I only use Unison for synching some stuff, not everything, and it only backs up files that have changed.

A company can not just barge into another country and demand their wants and rules be met

Aside: Really, it's not about the egos of scientists, or the perfection of our telescopes and instruments. Goodness knows, if they were so perfect, we wouldn't be begging for money to build new and better ones! :)

The link that pyrrho mentioned describes the basic reasons why baryons can't be all of the hypothesized dark matter. And since 1996 (when the article was written), the evidence has become vastly more convincing. I'll attempt to summarize.

Sure, we could hypothesize that the Universe is filled with "dim, normal stuff" like brown dwarfs, white dwarfs, lost airline luggage, missing socks, dryer lint... but we're just not able to see them. Fair enough. But there is a limit to this argument for numerous reasons.

• There are not enough baryons in the Universe. The Big Bang only made so many baryons, and this is something we can measure. The limits on the number of baryons in the Universe are quite tight -- only, say, 5% of the mass needed to give the Universe an uncurved geometry.

  Okay, so maybe we just live in an empty, open Universe! But numerous measurements of the curvature of the Universe, in particular recent observations of the cosmic microwave background itself suggest that the curvature is not open but uncurved. So we live in a Universe with plenty of gravitational matter of some form or another. Aside: we are gathering a huge amount of information by looking at the angular sizes of the bumps and dips in the cosmic microwave background, which is fossil radiation from the Big Bang and a few percent of the static you see on your TV when tuned to a blank UHF channel. This page shows what the CMB power spectra (that is, how many inhomogeneities occur at a given angular size) look like, and how changing various cosmological parameters has an effect on the spectrum you'd expect to see. Try out changing the baryon density -- the effect is quite pronounced. It also says that the Universe has the number of baryons that Big Bang theory says it should have.

• Even if we can't see brown dwarfs (or basketballs, for that matter) by their reflected light, we CAN infer their existence by their gravitational interactions with light, i.e. gravitational (micro)lensing. It's not that we "haven't looked hard enough" -- but rather that "if the Universe was full of brown dwarfs, there'd be tons of observable microlensing events". But microlensing events are exceedingly rare. In this case, the null result is interesting, because it highlights that baryonic matter is not as prolific as we want/need!

So this makes us all feel a bit uncomfortable, because either some of the fundamental tenets of cosmology are flawed (even though they explain nearly all of the observable Universe, right down to the abundances of the elements and the large scale structure of galaxies and the cosmic microwave background, the recession of galaxies etc.) ... OR ... the Universe is mostly filled with matter what is unlike anything we yet know how to explain.

It's going to be a fun ride! :)

So said gilroy:

I happen to agree with your point on this particular style issue, but I want to offer up this thought: The New York Times has a well-known Style Guide and, while I have no idea what it says about pluralizing acronyms, I am sure it says something. The writer and his/her editor are surely going to go by that, not a Web-based self-appointed guardian of grammar. Just because a lot of people contribute to a discussion, doesn't mean the discussion is authoritative (slashdot, anyone?).

My fellow Slashfriend, I am more than familiar with the concept of a Style Guide, having been employed at multiple professional publications.
While I must agree with you that I also have no idea what the NYT Style Guide happens to say in this instance, I *can* say that as an owner of Strunk & White's _Elements of Style_, the _Chicago Manual of Style_, and having written many times under Chicago, MLA, and APA guidelines, that I *seriously* doubt that the NYTSG differs on this issue from pretty much every Style Guide out there.

I agree with you that the NYTSG says something regarding this. I happen to think it probably agrees with every other style guide I've ever seen. This does not mean that the author or her editor followed it.



Much more importantly, one of the great strengths of the English language is its similarity to Perl: There's More Than One Way to Do It. Thankfully, we have no great temple of English usage, where Zen oracles tell we little people what the correct form is.

Indeed, I suppose that there is more than one way to do it.

Considering the reach and clout of the New York Times, I think it's fair to say that their Style Guide can be taken as an authority ... certainly at least as much as an Internet mailing list can.

Agreed. I just doubt seriously that she followed her Style Guide.

cheers!

A stripped down Redhat-based distrib entirely managed by a well-scripted web-interface they really can be locally administered by the Office Administrator. The install is short and sweet and with a few questions it sets up a well organized server offering 'bout anything a modern office would want all automagically.

Ok, actually it's all done off an impressive system of scripts and templates but as far as J. Random "Administrator" is concerned it just works, and all from the clean browser-interface. Groups and accounts, POP & IMAP, LDAP and Webmail, all come built-in. A hardy user community contributes their own extensive set of ports and script templates including user self-management web interfaces, MySQL administration, mp3 jukeboxes, log and queue management, etc.

I set this up on a donated Compaq box a year ago for a local youth services organization (read: Human Services-type folks who don't know anything about computers, aren't inclined to learn much, and really just want this stuff to work with a minimum of muss and fuss so they can get on with their real work) and they've loved it. Ok, actually they don't care: It just does what they need it to do, is easy to get to do those things, offers the services they needed and they're not interested beyond that, which is a Good Thing.

Oh yeah, services they use their E-Smith box for are:

• Firewall protecting their office network
• Caching speeding their web-browsing
• A filter blocking many of the web-ads
• A local email-server for their inter-office confidential email
• A NAT allowing them to save money on the ISP plan they use
• Shared File-Space
• Shared Address Book
• Shared Printers
• Personal Directories so everything isn't only stored on their individual aging PCs
• IMAP folders so all of their email records aren't only stored on their individual aging PCs

Personally I've got E-Smith servers in both of my residences (different countries) where I use a Unison implementation for E-Smith to keep both boxes synchronized. It also provides a handy VPN between both houses as well as offering all of the other services listed above. Next up it'll be hosting photo galleries and some web sites for the family as well as a Twiki server for friends to share.

Oh, and best thing about all of this? It runs on low end PIII's, 200MHZ w/ 128MB RAM, not speed demons but stable, reliable, secure, and very effective. Did I mention trivial to administer too?

http://nscp.upenn.edu/aix4.3html/cmds/aixcmds5/umo unt.htm works fine for me

The Online Books Page

Over 10,000 online books free to the public.

Yes, but just a couple. Some very industrious people compiled this list.

Even were the US the longest, it would have to be so by a good margin to stick out. Again, I don't necessarily think the current terms are appropriate. Judge Posner has criticized them well, and noted that the main problem is that because it is difficult to make money off materials in the public domain, there was little opposition to the Sonny Bono Act.

Yes, I said "nineteen fifty four," and not "nineteen eighty four."

The phrase of the day is "chilling effect," brought to you by the letters H, U, A, and C.

Or isn't anyone else thinking that TIA (and friends) is a little closer to the HUAC than Orwell's book? Just alias "Commies" to "terrorists," and it works just fine.

I mean this new plot is like, well, imagine -- naah, hold on, I have to say it -- imagine a Beowulf Cluster of Joe McCarthys...

...and you've got it about right.

Moore's law is not provable, but is disprovable, so should not be rejected on that basis.

On the other hand, it's probably wrong, after all Ninety percent of everything is crud.

On a smaller scale (personal), this is essentially what I do.

First, only some personal data is critical, not the GBs of operating systems and programs I can redownload/recompile if necessary. Things like documents, saved games (you'd think it's unimportent until you play the first 2/3s of Fallout 2 five times and can't stomach getting far enough to see how it all turns out, because you'd have to play that 2/3s again...), email maybe, whatever, but some limited amount. 10MB can go a long way... that's a lot of programming, for instance. (Been working on a project for about half a year now and I'm just ready to break 300KB of code...)

Then, set up a live backup amounst all the disks you have on various machines. I use unison so that I can change files in the repository on any machine and have the changes propogate correctly, instead of the unidirectional updates rsync does.

Use symlinks to put everything you need into one directory, and tell Unison to follow the symlinks, not archive them directly. Then just run that every so often on the machines, and you're set.

Once more of my family gets set up with always-on connections, I intend to set up a family-level repository of backed up files with Unison, so that "off-site backups" are a weekly script run without intervention by the family, making off-site backups across the state (or country, or world) easy. This will protect the scanned pictures and other things in the family heritage easily and effectively.

Which reminds me, the first always-on connection just came online and I really ought to talk to that member about a reciprocating backup setup...

The UPenn Online Books Page is an index to a total of more 17,000 online books in various locations. This includes all of the 3000-plus Project Gutenberg texts.

(Note that the Project Gutenberg texts are nice because they're in a completely plain-vanilla ASCII format, each work is in a single file, and the formatting conventions are fairly uniform across the collection).

Oh, don't overlook Project Gutenberg of Australia, as they offer quite a few works from around 1920 to 1950 which are in copyright in the U. S. but not in Australia. Wait, forget I said that.

Pretty impressive: at 17,000 works, the Internet is finally starting to approach the capacity of a (small) physical library. A major university library still is a couple of orders of magnitude bigger, however...

No...Copyright was introduced to give incentive to businesses and authors/artists to invest in and create works. The incentive being they would be better able to make $$$$$ from their works instead of having them pirated away.

You must belong to the Revisionist History Club.

No, you are a member of the Ignorant of History Club. I suggest you try reading the writings of the autors of the constitution and the bill of rights. They seriously considered making Patents and Copyrights unconstitutional. Failing that, a 19 year maximum on copyrights nearly made it into the Bill of Rights. The Bill of Rights for god sakes! They took this issue quite seriously!

I doubt you're going to make an effort to educate yourself, but in case you do here's a piece to get you started. Their motivation was ABSOLUTLY POSITIVELY NOT so someone can make $$$. The mostivation was to get ideas out into the public domain. They considered copyrights and patents an evil to be tolerated as a means of promoting the public domain.

As for the "great benefit to society" of the expiration of copyrights I need go no further than to Disney movies. Snow White, The Jungle Book, Peter Pan, Alice in Wonderland, and many more, all adapted from stories on which the copyright had EXPIRED. Almost every Disney movie ever made owes its very existance to the expiration of copyrighted works.

I'm not advocating that copyright be abolished, it serves a usefull function. The problem is that congress has lost sight of that purpose, and weathly corporations have been taking advantage of that and buying influence for private gain at public expense. The purpose of copyright is for PUBLIC BENEFIT. The fact that some people can make money in the process is a side effect, not a goal.

People are generally oblivious to the value of the public domain because essentially NOTHING has entered the public domain in DECADES. Here's a hypothetical: Imagine the original copyright duration was still in effect - 14 years. Everything from 1988 and earlier would be free for everyone to publish, view, and BUILD UPON. Can you imagine n public benefit to having Star Wars available in stores for $5? Or people making entirely NEW Star Wars movies based on the original? There's a tremendous amount of creative work lying unpublished and unavailable forever because the copyright on the inspiration never expires during the authors lifetime. Just look at the quantity of technicly illegal "fan fiction" floating around the internet.

-

Reality check... yes, 40 billion is a huge amount, but it's being spent on something CONSTRUCTIVE. How 'bout we shave 40B off our military budget and reinvest it in the space program? Then we WILL have our dual-torus artificial gravity stepping-stone-to-the-stars hotel in space in no time.

I'm in no way anti-military, but there's a reason the budget category is called "defense" and inventing hugely expensive toys to lob at people not in our political favor (who should be just left to rot in their own little happy medieval society for all I care... and strangely, it's because we won't do just that that they claim to attack us... but I digress) just doesn't seem very defensive to me at this time.

But back to the topic... mmmm... space stations...

Let me prepend this by saying that I really do not like ocaml or other ml languages, but if you're into functional languages, you may like it. There are some things that are done right, like a very strong type system.

Unison, a file-sychronization tool, and MLDonkey, a P2P client that supports just about every significant P2P protocol out there (except the closed version of FastTrack) are both written in ocaml. That's all I know of, though.

Give me something like ocaml but without type inference (most annoying invention of all time) and not a functional language (sorry, just don't think that way), and I'd be pretty happy. It's about the fastest safe language out there, followed closely by eiffel.

These dudes beat you to it.

Steve

I've read hundreds of books on the Palm/Visor in the last two years and ALL FREE. Most were linked from online books in text format. Download 'em and run 'em through MakeDocW, which automatically puts them in the Install directory for next sync.

Better than rsync:

unison - I keep my desktop, server, and laptop synchronized over SSL connections. Like rsync, it sends minimal changes to keep source trees up to date. I can sync over a gig in my home directories in much less than a minute unless I dumped a whole bunch of new stuff on there.

http://www.cis.upenn.edu/~bcpierce/unison/

Their zipped version is 1,220,608 bytes.

I don't know anything about .Mac, but if the main point is backups and file synchronization, why is proprietary software necessary? Hfspax works great for archiving files without losing their macintosh resource fork, and unison is a wonderful file syncrhonization that I use to sync up my various Linux and MacOS X accounts.

How many books are we talking about? Those out of copyright and not in PG.

Well, under the current state of US Copyright Law (TM), anything before 1923 is public domain. In addition, some things after 1923 are public domain due to legal technicalities (e.g., forgetting to re-register the copyright, explicit gifts to the public domain, etc.). So, that number is very big and pretty much uncalculable.

According to the latest Project Gutenberg Weekly Newsletter (which are sent to the Book People Mailing List, archived here), there are 6267 books in Project Gutenberg.

So, for a simple calculation:

how_many_books_we_are_talking_about = ${Number of books printed before 1923} - 6267

Check out the following for a start:

• Books in Progress and Requested
• Steve Harris' PG To-do List
• David Price's In-Progress Page (some have been "in-progress" for quite awhile now, so they are probably free to grab)

At the moment I use gaim. It is very similar to Trillian. However I use use gaim both at home and at work, and therefore I have to spend time adding every buddy twice, and that annoys me. I guess that I can solve this problem with the unison file syncronizer , but it would rather solve it by convincing my work so set up a Jabber server. In Jabber the buddy list is put in the server, so I only have to add each buddy once. Of course I would feel badly about using a public Jabber server, because I don't want my private messages to go through a server that I cannot trust.

His idea is that all possible mathematical structures exist, and that we live in one of them! At some level, physics can be considered a branch of mathematics. Hence our universe can be considered as an enormously complicated mathematical structure. The question is, why this structure instead of some other?

His answer is that all mathematical structures exist, but that most of them are unsuitable for life. The paper linked above analyzes many different possibilities in terms of numbers of dimensions, numbers of time dimensions (yes, you could conceive of a universe with two-dimensional time), various other parameters, and he shows that structures that we would think of as living would have a hard time existing in universes much different from our own.

The Tegmark model can be thought of as the simplest possible physical theory. If physics is reducible to mathematics, then saying that all mathematical structures exist can be put more simply: Everything exists.

A similar model based on computation is proposed by Juergen Schmidhuber. Rather than Tegmark's mathematical structures, Schmidhuber proposes that all computations exist. Given that any mathematical model of a universe can be simulated by a computer program, these two formulations are roughly equivalent.

But Schmidhuber's approach has the advantage that it provides a natural way to say that some universes are more probable than others: namely, universes with short programs have more "measure" than universes with long programs. It follows that our universe probably has a relatively short program, which therefore explains why we observe that physical laws are mathematically simple.

It's pretty heavy stuff, but certainly exciting to see that researchers are (somewhat reluctantly) beginning to entertain multiverse models. The more ambitious "everything exists" theories are still too extreme for the mainstream, but I suspect that they, too, will get increasing attention over the next few decades.

His idea is that all possible mathematical structures exist, and that we live in one of them! At some level, physics can be considered a branch of mathematics. Hence our universe can be considered as an enormously complicated mathematical structure. The question is, why this structure instead of some other?

His answer is that all mathematical structures exist, but that most of them are unsuitable for life. The paper linked above analyzes many different possibilities in terms of numbers of dimensions, numbers of time dimensions (yes, you could conceive of a universe with two-dimensional time), various other parameters, and he shows that structures that we would think of as living would have a hard time existing in universes much different from our own.

The Tegmark model can be thought of as the simplest possible physical theory. If physics is reducible to mathematics, then saying that all mathematical structures exist can be put more simply: Everything exists.

A similar model based on computation is proposed by Juergen Schmidhuber. Rather than Tegmark's mathematical structures, Schmidhuber proposes that all computations exist. Given that any mathematical model of a universe can be simulated by a computer program, these two formulations are roughly equivalent.

But Schmidhuber's approach has the advantage that it provides a natural way to say that some universes are more probable than others: namely, universes with short programs have more "measure" than universes with long programs. It follows that our universe probably has a relatively short program, which therefore explains why we observe that physical laws are mathematically simple.

It's pretty heavy stuff, but certainly exciting to see that researchers are (somewhat reluctantly) beginning to entertain multiverse models. The more ambitious "everything exists" theories are still too extreme for the mainstream, but I suspect that they, too, will get increasing attention over the next few decades.

This page says that "I am Curious Yellow is the title of a Swedish film from 1967 (in Swedish it's Jag aer nyfiken - gul). The following plot summary comes from the Internet Movie Database:

Lena, aged twenty, wants to know all she can about life and reality. She collects information on everyone and everything, storing her findings in an enormous archive. She experiments with relationships, political activism, and meditation. Meanwhile, the actors, director and crew are shown in a humorous parallel plot about the making of the film and their reactions to the story and each other. Nudity, explicit sex, and controversial politics kept this film from being shown in the US while its seizure by Customs was appealed."

Here's the script (best read after ingesting copious amounts of mind-altering drugs, otherwise it doesn't make much sense).

When I was taking engineering at UofT in the 90's, we had a similar event. Only this time, instead of wasting money on a quickly outdated CRAY, they wasted WAY MORE money on an even MORE quickly outdated "Thinking Machines" supercomputer. I recall they spent something like $20 million to get it to work before just giving up, I'll be the engineers in the Sanford Fleming building use the cabinets for a fridge to hold beer these days.