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Helfgott has not (yet) published his paper. The only thing I could find was an abstract, in Spanish. . He works at the University of Göttingen, and so probably knows basic German. Me speaking German, I'm going to gently ask him for his paper by email.

http://xxicla.dm.uba.ar/viewAb...

That's not the general case. I attend to the FIUBA, so obviously it's one with the highest rates of laptops per student. Everybody know that you don't leave a computer alone, but it's not that paranoiac shit that if you leave it alone it'll be stolen.

The reality is that as a student you have so much to loose (being expelled), that even if you are a thieve you wouldn't do it in your own house.
It's the same thing in the dangerous neighbourhoods. you don't steal from your neighbour because you could be fucked up.

As often seems to be the case with these news articles about teenage prodigies, this has been overhyped. It turns out that what he did is not new and is not a complete solution to the problem.
Parker, Am J Phys 45 (1977) 606 has a summary of the preexisting results. The expression immediately after equation 23 is the constant of the motion that Ray rediscovered.

A reddit user has a nice simple derivation: http://redd.it/u74no (Note that there is an error because he claims to have proved it in general, but it's only valid when v (the vertical velocity) is positive.)

For more on the history of the problem:

Synge and Griffith, Principles of Mechanics, p.~154 http://archive.org/details/principlesofmech031468mbp

Whittaker, A treatise on the analytical dynamics of particles and rigid bodies, p.~229 http://archive.org/details/treatisanalytdyn00whitrich

According to Whittaker this was first done by D'Alembert in 1744.

I've used Oregano on Ubuntu with not very many problems. My original reason for trying it out was that the academic demo for OrCAD wouldn't simulate circuits large enough for my projects at school. I've found that it duplicates most of the features we used in courses on OrCAD. Oregano

Inkscape is currently undergoing a Google Summer of code project to improve it's applicability for blueprints, which is why I mentioned it.

There's no interest in duplicating AutoCAD because it's a massive load of work. Somehow you've taken the idea that people not getting together and duplicating AutoCAD's massive infrastructure and lock-in for ignorance of Engineering principles and design. Autodesk can dig themselves out of the hole they're in; they have Linux experts on hand (to support Maya) to start digging themselves out with. I know tons of places that want Linux in their shop; but none want the first mover disadvantage of funding whatever replaces AutoCAD. They'll probably look at things like QCad with more lenient eyes than yourself.

I understand the need for engineering design tools; spice is a critical analysis tool, and at some point I'd love to see Oregano picked up under GSoC or some other academic project. Fedora has Electronic Lab spin that seems neat. I suppose at the end of the day, open source is written by those who need it can can write it, and EE's write code more often than architects.

Sure,
http://data.fas.harvard.edu/numerical_stability/g3 009.pdf
http://www.lfp.uba.ar/moreno/TErrores2004/MSExcel/ statproc.pdf

And you can always search google for more, excel is widely known for being mathematically inaccurate.

"though excel really is the best spreadsheet software that I have yet seen on any platform."

For some uses maybe, but certainly not for all. Excel is notorious among statisticians and scientists for awful accuracy and calculation bugs that have gone unfixed for several versions (1). For statistical analysis the answers Excel give are sometimes wrong by orders of magnitude. We're talking about completely ridiculous answers rather than simply inaccurate ones.

Plotting colourful graphs are cute enough, but getting the numbers right should be the first priority of any spreadsheet.

Gnumeric on the other hand has deservedly (2) developed a very good reputation for accuracy over the last years.

1. http://data.fas.harvard.edu/numerical_stability/g3 009.pdf
2. http://www.lfp.uba.ar/moreno/TErrores2004/MSExcel/ statproc.pdf

I quote from 2:
"(...) persons who wish to use Excel for statistical purposes should exercise extreme caution.
We note that persons who use the spreadsheet Gnumeric need not exercise such
caution."

And:
"One could argue that it is acceptable to use Excel for summary statistics, one-way ANOVA, linear regression, and some of the statistical distributions, but we are extremely
concerned about Microsoft's cavalier attitude toward accuracy."

About Gnumeric:
"It is interesting to observe that the open source Excel-clone called "Gnumeric" was such a good clone that it even had errors
similar to Excel. However, the developers of Gnumeric, who are part-time volunteers with no R&D budget, chose to deal with these errors in a different way: by implementing correct
fixes. See McCullough (2004a) for a discussion."

My college is still using ancient DOS versions of Orcad (because upgrades are too expensive for them)and an old B2 Logic (TTL logic simulator) that is pretty outdated. They get the job done though, when you just need to have basic circuit design and simulation programs. Honestly, GPL circuit simulators are pretty good, and free. I've been able to pretty much do everything that I need to do with Oregano http://arrakis.gforge.lug.fi.uba.ar/index.php , a front-end to GNU Cap and ngSpice.

As far as I remember 2 years ago in the UBA (University of Buenos Aires) two profesors discover how does that part of the bird brain works and reproduced it in a computer, with great repercution in the media (at least here in Argentina).
I'm looking for the article in any newspaper database to post it here...

Anyone employing Excel for any statistical calculations should get a nice chill from reading any of B.D McCullough's papers on Microsoft's egregious (and mostly uncorrected or corrected badly) errors in this area.

Click here for a link to one of his recent critiques entitled:

On the accuracy of statistical procedures in Microsoft Excel 2003

Here is a nice quote from the above paper:

"...persons who wish to use Excel for statistical purposes should exercise extreme caution...Persons desiring to conduct statistical analyses of data are advised not to use Excel 2003."

"Excel is like a bikini. What it reveals is suggestive, but what it conceals is vital." -- apologies to Aaron Levenstein

If I am reading things correctly it would seem, that both the "Squalid Staters" and Chaitin are coming from the same angle. Both reckon that any maths we can derive to describe the physical world are almost fluke, and that underlying everything is sheer randomness. Fascinating Stuff. Can anyone offer a more qualified comparison of these two areas?