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Here it is. Just spell-it out to them digit by digit and they will be all over you when you finish.

Yep. I remember reading a Number Theory book long ago that Skewe's number 10^10^10^34 was "the largest number which has ever served any definite purpose in mathematics", but apparently, things have changed since then. The largest meaningful (but useless, as you pointed out) number used is apparently Graham's Number, which has even been listed by the Guinness Book of World Records as such. Tetration is explained here, or quite a lot of notation is explained here.

The best page about large numbers, however, is clearly the one at MROB, beautifully written.

But the amusing thing about this Graham's Number is that it is an upper bound on some quantity, which experts believe is equal to 6. That's right, SIX. So it's not only the largest number ever used; it's also probably the worst upper-bound ever :)

Yep. I remember reading a Number Theory book long ago that Skewe's number 10^10^10^34 was "the largest number which has ever served any definite purpose in mathematics", but apparently, things have changed since then. The largest meaningful (but useless, as you pointed out) number used is apparently Graham's Number, which has even been listed by the Guinness Book of World Records as such. Tetration is explained here, or quite a lot of notation is explained here.

The best page about large numbers, however, is clearly the one at MROB, beautifully written.

But the amusing thing about this Graham's Number is that it is an upper bound on some quantity, which experts believe is equal to 6. That's right, SIX. So it's not only the largest number ever used; it's also probably the worst upper-bound ever :)

Read The Eye of Argon for the full splendour!

Yes, it's a corporate site, but scroll down the site for some good links to follow to learn about HAPs and their use as communications infrastructure.

http://www.elec.york.ac.uk/comms/haps.html

On SourceForge, look up Webwork, Moodle, AIM (Assessment In Mathematics), and LON-CAPA, or look at STACK here. Webwork, AIM and STACK are primarily geared towards delivering math homework and I know that Webwork in particular can deliver fairly sophisticated problems. Webwork is entirely free and has several large free problem libraries, AIM is costly in that it uses Maple as one of its components, but STACK is similar and replaces Maple with Maxima or Octave (I think).

Moodle and LON-CAPA are more general. Moodle looks mangageable, but LON-CAPA looks huge and bulky to me and is probably very much a group project.

In the proprietary realm, I like the ALEKS online system for teaching basic mathematics, and their statistics looks good, too. No, I don't work for them or own their stock. I don't care at all for any of the other proprietary systems I've come into contact with, and I've seen many of them.

Why just choose between Qwerty or Dvorak?
Why not design your own?

A one-handed keyboard, for instance:

http://www-users.cs.york.ac.uk/~ianb/broster.co.uk /keyboard.html

And the author of this keyboard has no problems
switching between his own design and Qwerty.

Best Book on Solar Sails:
http://www-users.cs.york.ac.uk/~susan/sf/books/c/c larke.htm#5484
Arthur C. Clarke, editor. Project Solar Sail. Roc/Penguin. 1990
Contents:
Poul Anderson. Sunjammer. 1964
Arthur C. Clarke. The Wind From the Sun. 1963
Arthur C. Clarke. The Winds of Space (forward to Project Solar Sail). 1990
Isaac Asimov. Sailing the Void (introduction to Project Solar Sail). 1990
Ray Bradbury, Jonathan V. Post. To Sail Beyond the Sun (A Luminous Collage). 1990
K. Eric Drexler. The Canvas of Night. 1990
David Brin. Ice Pilot. 1990
Jonathan Eberhart. A Solar Privateer. 1981
Chauncey Uphoff, Jonathan V. Post. A Rebel Technology Comes Alive
Alfred Lord Tennyson. Argosies of Magic Sails
Brian Palaszewski. Ion Propulsion: The Solar Sail's Competition. 1990
Charles Sheffield. The Grand Tour. 1987
Scott E. Green. Lightsail. 1990
Kevin J. Anderson, Doug Beason. Rescue at L-5. 1990
Robert L. Forward, Joel Davis. Lightsails to the Stars. 1990
Joe Clifford Faust. Goodnight, Children. 1990
Robert L. Staehle, Louis Friedman. Solar Sails in an Interplanetary Economy. 1990
Arthur C. Clarke. Afterword to "Project Solar Sail". 1990
Larry Niven. The Fourth Profession. 1971

It seems to me TFA has have missed the point of Google Scholar. Web of science does abstract, keyword and title searches. And it's very good at them. Google Scholar does full text searches. If I want to know if there has been a study on the effects of ibuprofen on slugs (or whatever), I go to WoS. However, sometimes you want something in the details, which isn't mentioned in the abstract or title. I sometimes want papers that have used a particular statistical technique - I'm not (very) interested in the substantive content, I just want a nice example. WoS - no use at all. Google Scholar - excellent.

When you get your results, WOS gives you the abstract. Google Scholar points you to the full text source - often you have to pay for it, but you have it there.

People who get obsessive about systematically reviewing the literature and making sure that they have accessed everything on the subject are never going to use Google Scholar. People who want to know more about a subject are better off with Google Scholar.

On citation searches, WoS wins hands down (IMHO).

You accidently create a dozen instances of yourself and shoot them all in the foot. Providing emergency medical assistance is impossible since you can't tell which are bitwise copies and which are just pointing at others and saying "That's me, over there."

Source

He shouldn't be putting down the Mac like that. The degree of compatability with other systems that the Macintosh provides is amazing. For example, they can even network with alien spacecraft, and even provide you a "uploading virus" dialog box.

But look what it did to his hair !
http://www-student.cs.york.ac.uk/~jw222/oops.jpg

This isn't terribly new - uber-l33t people have been doing this for ages. See http://www-student.cs.york.ac.uk/~jw222/keyb.jpg.

The benefits, to my mind, are quite great. This applies especially to Dvorakers, for whom the QWERTY key markings are at best an annoyance. It also stops people who can't touch type from using my computer!

But of course, we should remember that Real Programmers don't use PASCAL

That was before Borland introduced Turbo Pascal, which everybody marvelled at. They sold a zillion pascal compilers and that was their bread and butter for a long time. Everybody was saying how they were gonna reuse all this pascal code they were writing and it really was the shiznit.

Then the Mac gained credibility with the laserprinter and Think C had a C++ compiler and everybody was starstruck by the term "object oriented," which blinded everybody until the internet came along with a new set of buzzwords that inflated a nice bubble filled mostly with worthless gas.

I do not see anybody falling over each other to reuse a lot of that old pascal code. And even though everybody says how they can reuse C++ stuff, it seems like every time I read details about some software project they are having to reinvent errr rewrite the wheel. Or if it's not that it's someone else's spaghetti code they can't read.

The first computer language I learned was was Fortran at a terminal with computer time you had to buy in CPU seconds. It was a sperry univac that had a rotating drum (not disk) and I believe it was a five megger --> 5 megabytes. The entire university had only a couple of cpm computers in the library for student use. When I enquired about them nobody knew if they worked and there was no software for them. This was 1983. Needless to say wordprocessing was a bitch back then, and the student paper was filled with ads for people who would do typing for you. Anyway, I digress.

I was told how gosh darn important Fortran was going to be in my chosen field of electrical engineering. Well, it wasn't and isn't. I won't tell you what the school is, but I will say they are responsible for the world-changing discovery of cold fusion. They have since become important in the areas of supercomputing and contribute a lot to Linux. I would like to think that there is irony there, but I have my doubts.

Through my years of learning, I think I like straight pascal the most. It is elegant, and bug hunting MUCH more straightforward. Though I am sure to findle ample amounts of people who will disagree with me on slashdot. But trust me, I've been there, done that, and got the t-shirt.

I mention this because the date of the the article is 1983, and even though it was (is) a joke, it hits close to home.

But of course, we should remember that Real Programmers don't use PASCAL"

:-)

How to shoot yourself in the foot... http://www-users.cs.york.ac.uk/~susan/joke/foot.ht m

Fortress has a number of interesting features, including support for Unicode characters in code, enabling code to look more like formal mathematical expressions. First thing I think of...APL. Wonder if we'll buy new keyboard with this as well.

Being gay is wrong. It says so in the Bible.

The Bible also says that it is alright to sell women into slavery and other ludicrous things. I understand that you believe strongly in the documents of your faith, but I really doubt that Jesus would approve of discrimination towards anyone for any reason, or any form of hate, even if they are a "sinner"

Well, just googling for quantum computer gave me as very first hit http://www.cs.caltech.edu/~westside/quantum-intro. html, which looks quite good to me.

Also under the first links is http://www.qubit.org/library/intros/comp/comp.html , which also looks quite good to me. (the whole www.qubit.org is interesting, BTW).

If you want to go a bit more in depth, I think http://www-users.cs.york.ac.uk/~schmuel/comp/comp. html looks good.

And if you can't wait to program a QC, then you might be interested in QCL, the quantum computation language. Yes, you can download a compiler there (which of course only simulates a QC, since current computers don't yet come with quantum processors :-)).

You are quite right, however, in that buffer overflow is a result of careless programming. Making assumptions about length of strings is fine if you're in a purely academic setting and under time constratints to get your programming assignments done... besides, your professors usually will tell you that it's fine. I do wish, however, they'd emphasize that while it's fine in a controlled environment, in the real world, you have to provide for checks against buffer lengths, etc.

C is still used for a lot of things because of its flexibility. Yes, you can very easily shoot yourself in the foot, but with the flexibility and power comes greater responsibility... which means anyone who uses it needs to be vigilant, always expecting the unexpected.

That crash was due to pilot error, it had nothing to do with any "computer override" - indeed, the pilot had had to switch off several safety systems to make the flypast - that was a theory that was quickly discounted by the investigation. Please read a previous slashdot post of mine where I rebutted a previous occurance of this myth, along with a link to an excellent post to safety critical on this AirBus crash.

The computers were fine. It was pilot error, compounded several times over.

And the truly literate readership would probably prefer the /. grammarian posers would stop harping on obsolete 13th Century grammatical rules based on the inherent structural inflexibility of Latin. Which has, incidentally, been discredited by every reputable expert on modern English usage and style.

and the infamous "DO 100 I = 1.10" problem.

...which isn't particularly infamous, when you realize that this problem never caused the demise of a spacecraft, unlike the urban legend would have us believe.

Please, that video is not of Airbus demonstrating auto-landing. It's of an Air France 'demo' slow, low-level fly-past at an airfield (ie fly along the runway and continue on), in 'unclean' configuration (flaps and gear down, similar to landing configuration - but it's not doing an auto-landing.).

The accident report blamed human error, particularly the captain. He was ill-prepared, partly Air France's fault as the airfield map they gave him did not show the trees, and was responsible for several errors. The barometric altimeter was miscalibrated by 67 feet, the captain then ignored the voice-sounded warning of 100feet from the (very accurate) radio altimeter and trusted the barometric altimeter instead. He then flew the plane in an attitude and configuration in which it could not recover quickly from, and finally, he applied power to recover too late (big turbofans take time to spool up from idle and start producing power).

The captain maintains the plane did not respond as it should have done. Firstly, he claims one engine did not respond within the time it should have (which is plausible) and secondly that the flight software malfunctioned and did not respond correctly to flight-control input (which is slightly less plausible). There also claims that the FDR was tampered with after the accident (claims are that 4s were cut, to make it seem like the captain applied power 4s too late).

The captain may be right, however even so he was negligent and made the crucial mistake of misjudging his altitude. Had he flown the fly-past at the intended AGL of 100 feet, the accident would never have occured, regardless of the other factors.

See, eg, this safety-critical post.

PS: "Autoland" has been around a long time, Cat-III equipped runways have been around since the 1970s i think, possibly the 1960s. It still requires a human to eyeball the runway though and make the final decision, to 50feet above runway or so for Cat-IIIb.

talking about plug in architecture.... With regards to the guys at B3ta whose image i tidied up a bit

This never happened before in humanity's recorded history :-)

And besides, how do you apply the word "correctly" to the art of spaceflight? There is no single correct way to do things. There is no even a single correct way to cross the street, as far as I know. If you require perfection then I guess you should remain dirtside until some [supposedly] benevolent extraterrestrials, like Qax, offer you a free ride in one of their ships. Anything else involves risk and uncertainty, and most definitely something somewhere will be done incorrectly, even if you throw resources at the problem. To err is human.

The word in the original Greek seems to be a much more specific term (meaning "love of money") than the Latin "cupiditas". Also, the context of the saying makes it clear that "money" is in view.

This points to an analysis of the findings of the crash investigation, the Captains version of events and subsequent independent investigations of the crash records and FDR information.

This analysis comments :

The official report clearly states that the engines performed to specification. Asseline [Pilot-in-command] states that he did not get power as quickly as he expected it, following the selection of TOGA thrust. According to Asseline's timings, 9 seconds elapsed between the TOGA command and the spool-up of the engines, instead of the 5 seconds that the engines are physically capable of (and that the official report claimed). In addition, the pitch control did not follow the pilot's commands.

and also this comment :

The controls were not following the commands of the pilot throughout the flight, but during the last few seconds, the elevators moved towards a position corresponding to nose down, although the captain was holding the stick back.

There can be no doubt that the Captain was flying towards the edge of the flight envelope. However, there are still question marks over this accident and the investigation. Bear in mind that a conclusion that there may have been problems with the fly-by-wire software would have cost Airbus serious amounts of money in redesign, testing etc, not to mention possible loss of revenue. Also, Airbus is a standard-bearer for the industrial might of France - the possibility of pressure for a more 'favourable' intrepretation of events cannot be ruled out.

In the end, the whole incident may simply come down to too much faith in technology by everyone involved - a least some lessons will have learned from this incident.

A !tang would folow "all die" with "O the embarrassment."

I heard this song about this very subject...

http://www.swordmaiden.com/history/sca/illseeyours ix.php

http://www-users.cs.york.ac.uk/~susan/sf/filk/seey rsix.htm

A student plagarized a paper for his 3rd year project-report. To cover his tracks, he steals the original paper from the library. Then, he does the same thing for an essay, but fails to realise that the essay he is plagarizing is one of the references given in the assignment.

It is in this section. Just scroll down to the bit with "Student copies paper from Phys" in it.

A student plagarized a paper for his 3rd year project-report. To cover his tracks, he steals the original paper from the library. Then, he does the same thing for an essay, but fails to realise that the essay he is plagarizing is one of the references given in the assignment.

It is in this section. Just scroll down to the bit with "Student copies paper from Phys" in it.

Apart from googolplex, the highest named number is actually one centillion, which is 10 ^ 600.

What about Graham's Number? It can even be expressed by normal exponential notation.

This site purports to give an overview. I don't know much of anything about quantum physics, so I can't really summarize it. I didn't really even read it, though it looks okay. ;-)

Oops. Mean to post this link.

The pilots put the aircraft in a mode suitable for the planned flyby, rather than for a landing. Specifically they disconnected the "alpha floor" inhibitor so that their display would not be spoilt by computer inputs.

The major cause of the crash was that the flyby occurred lower than intended, due to a discrepancy in the altimeter display. The radiosonde reported the correct height, but this was not observed or heard by the pilots, who were relying on the faulty bariometric display. Consequently they were lower than surrounding obstacles and were unable to regain full power in time to escape impact.

A report may be seen here and a discussion on the debate over the crash may be seen here.

ever wonder what horse's ass came up with this specification?


The US Standard railroad gauge (distance between the rails) is 4 feet, 8.5 inches. That's an exceedingly odd number. Why was that gauge used? Because that's the way they built them in England, and the US railroads were built by English expatriates.

Why did the English people build them like that? Because the first rail lines were built by the same people who built the pre-railroad tramways, and that's the gauge they used.

Why did they use that gauge then? Because the people who built the tramways used the same jigs and tools that they used for building wagons, which used that wheel spacing.

Okay! Why did the wagons use that odd wheel spacing? Well, if they tried to use any other spacing the wagons would break on some of the old, long distance roads, because that's the spacing of the old wheel ruts.

So who built these old rutted roads? The first long distance roads in Europe were built by Imperial Rome for the benefit of their legions. The roads have been used ever since.

And the ruts? The initial ruts, which everyone else had to match for fear of destroying their wagons, were first made by Roman war chariots. Since the chariots were made for or by Imperial Rome they were all alike in the matter of wheel spacing.

Thus, we have the answer to the original question. The United States standard railroad gauge of 4 feet, 8.5 inches derives from the original specification for an Imperial Roman army war chariot. Specs and Bureaucracies live forever.

So, the next time you are handed a specification and wonder what horse's ass came up with it, you may be exactly right. Because the Imperial Roman chariots were made to be just wide enough to accommodate the back ends of two war horses.

I think the main issue with Java is not the processor, but several other qualities that, while highly desirable for a general purpose language, are unacceptable for real-time systems (garbage collection is one of them).

This is why there's been work for a real-time version of Java for a number of years now (see here). Incidentally this is what kicked of the JCP (it's JSR-001 :)), and according to my Concurrent and Realtime Programming in Java lecturer (Andy Wellings, who sits in the Technical Interpretation Committee for this JSR), NASA is quite interested in this as an option for its future missions to Mars.

"I disapprove of what you say, but I will defend to the death your right to say it"

Vocaloid has been covered on Slashdot before. It is one of the many impressive projects to have at least in part come out of the Music Technology Group at Institut Universitari de L'Audiovisual in Barcelona.

This is one of many impressive Music Technology groups in the world who is kind enough to provide us with open source software such as CLAM. Similarly there are some groups out there doing interesting things. Needless to say, I could link all day...

I am a graduate student in this field

http://www.york.ac.uk/admin/presspr/pressreleases/ broadbandhaps.htm

I think the more likely scenario is that they'll start charging you for a paper bill and offer to let you do it online for free.

That would seem to be the case, except that most of the Real World doesn't know .pdf from PCP, and will throw a fit if someone tells them they'll get charged extra for paying bills the way they've always done. Once again, Neo-Luddism is a Good Thing.

In the other direction, I *did* get a $5 credit from Citibank for switching to paperless. It was no problem -- I'd been paying online for more than a year before I decided to go for it. The only catch was that I had to stay paperless for ~6 months before you got the credit. It was a token amount -- less than 5% of what I was paying in interest (ouch!), but it's the thought that counts.

I went paperless with Verizon Wireless for a different reason -- I was getting 20+ pages of billing each month, and got tired of shredding it. Interestingly, the wireless co's seem to charge extra for "detailed billing" -- but cellular is "new tech", so there's no "way it was done before" to get in their way.

On the other hand, back a few years ago, I tried going paperless with a bill -- don't remember which. Back then, though, I didn't have a budget and racked up mucho late fees by forgetting to pay on time. Paperless is cool, but if there's *any* chance you'll forget to pay, avoid paperless like teh plague.

Maybe, but you could get Kermit on just about every platform under the sun.

Which was why it was great. Back in the early 80's it was the only thing I could get for all of my hardware. In some cases I had X & Y modem and in some cases, X, Y and Z. But the biggest reason why was that, almost twenty years ago, I used to it transfer software, data and my thesis to and from my trusty BBC Micro to York University's VAX mainframe via another BBC Micro that was connected to it. It was the only way I got data to and from the outside world.

How to Shoot Yourself In the Foot
Developer's Insight, December 1991 (approx version)

C: You shoot yourself in the foot.

C++: You accidently create a dozen instances of yourself and shoot them all in the foot. Providing emergency medical assistance is impossible since you can't tell which are bitwise copies and which are just pointing at others and saying "That's me, over there."

FORTRAN: You shoot yourself in each toe, iteratively, until you run out of toes, then you read in the next foot and repeat. If you run out of bullets, you continue anyway because you have no exception-handling facility.

Modula-2: After realizing that you can't actually accomplish anything in this language, you shoot yourself in the head.

COBOL: USEing a COLT 45 HANDGUN, AIM gun at LEG.FOOT, THEN place ARM.HAND.FINGER on HANDGUN.TRIGGER and SQUEEZE. THEN return HANDGUN to HOLSTER. CHECK whether shoelace needs to be retied.

Lisp: You shoot yourself in the appendage which holds the gun with which you shoot yourself in the appendage which holds the gun with which you shoot yourself in the appendage which holds...

BASIC: Shoot yourself in the foot with a water pistol. On big systems, continue until entire lower body is waterlogged.

Forth: Foot yourself in the shoot.

APL: You shoot yourself in the foot; then spend all day figuring out how to do it in fewer characters.

Pascal: The compiler won't let you shoot yourself in the foot.

Snobol: If you succeed, shoot yourself in the left foot. If you fail, shoot yourself in the right foot.

HyperTalk: Put the first bullet of the gun into foot left of leg of you. Answer the result.

Prolog: You tell your program you want to be shot in the foot. The program figures out how to do it, but the syntax doesn't allow it to explain.

370 JCL: You send your foot down to MIS with a 4000-page document explaining how you want it to be shot. Three years later, your foot comes back deep-fried.

It's mentioned on page 130 of Goedel, Escher, Bach: An Eternal Golden Braid..
"The proverbial German phenomenon of the "verb-at-the-end", about which droll tales of absent-minded professors who would begin a sentence, ramble on for an entire lecture, and then finish up by rattling off a string of verbs by which their audience, for whom the stack had long since lost its coherance, would be totally nonplussed, are told, is an excellent example of linguistic pushing and popping. The confusion among the audience that out-of-order popping from from the stack onto which the professor's verbs had been pushed, is amusing to imagine, could engender."

check out http://www-users.cs.york.ac.uk/~alistair/research/ dphil/jckh/altcomm.html Other whistle languages include articulation so that consonants interrupt the flow of the whistle. The people from Aas in the Pyrenees speak a Spanish-derived dialect which used to be adapted into a whistle language in a similar way to the Silbo Gomera whistle language used by shepherds high up in the mountains in the Canary Island of La Gomera (Classe 1957). Both languages share common traits: the Spanish linguistic framework, the method of whistling, the similar form of signals and the functional purpose of the signalling. http://www.google.com.au/search?hl=en&ie=UTF-8&oe= UTF-8&q=%2Bwhistling+%2Blanguage&btnG=Google+Searc h&meta=

Here are "Clarke's Three Laws", including "Any sufficiently advanced technology is indistinguishable from magic.". In "Magic", Asmiov was speculating on whether the reverse was true, but Asimov was hardly the first to reverse Clarke's quote.

I was at York University and it was great. Ah you don't mean this University of York do you! I find it interesting to my old university is relatively new considering the city is getting near to 2000 years old.

Reviews are here and here, e.g.

And here is a google search on here and the book.

Also fluoride is definitely a poison and is classified as such unless its use is medicinal, its addition to common drinking water therefore violates the Human Rights of citizens of the EU.

It's also interesting to note that the water companies in the UK only want to add it providing the goverment indemnifies them against any lawsuits that might result if it ever does get proven to be bad for people!

So I really don't think that was such a good analogy to use in the original article.