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Comment: Believe it or not... (Score 5, Informative) 101

by Landak (#40774065) Attached to: City Council Ordered To Stop CCTV In Taxi Cabs
The organisation doing the "telling off" here, the Information Commissioner's Office, is actually surprisingly good at these sorts of cases, on these sorts of scales. I know someone who was being followed by his landlord (by PIs -- looking for any breach of his tenancy agreement), and the ICO prosecuted all involved; a solicitor was disbarred and the landlord might face criminal prosecutions. In this case, the relatively small bit of government -- a city council, the smallest 'unit of democracy' in the UK -- being told off here has no choice but to take the ruling and stop taping everyone's conversation (and/or sexy fun time) in the back of a cab.

Quite why it is that the ICO can tell off Southampton Council for recording people routinely, and yet can do nothing about the fact that everyone's movements across and through London are routinely tracked, however, escapes me. There are more CCTV cameras in london per capita than anywhere else in the world; one need only walk around outside and be followed, tracked and dated whenever you're going anywhere. Automatic CCTV numberplate recognition algorithm will automatically fine you for stopping on a (double) yellow line for more than a minute, or for straying into a bus (or, now, unfortunately, "Games") lane, irrespective of whether or not you had any choice in the matter. I find it depressing that the specific extra-governmental regulatory body designed to stop these sorts of things is so powerless when it comes down to telling off people who actually are important.

+ - Light Table - a new IDE concept->

Submitted by omar.sahal
omar.sahal (687649) writes "Bret Victor (covered previously on slashdot) demoed the idea of instant feedback on your code. Victor's concept runs a little like a interpretor on your code, but in realtime. This allows the programer to instantly see what his programe is doing. Chris Granger has turned this novel idea into Light Table — a new IDE designed to make use of the Victor's insights.

Bret Victor — Inventing on Principle —
Update on the project —"

Link to Original Source

+ - A 3D-Printing Makeover: Restoring China's Forbidden City->

Submitted by jcho5
jcho5 (2602715) writes "China's 600-year-old Forbidden City is looking less forbidding these days. As part of a major restoration, the Chinese Palace museum will use 3D-Printers to re-manufacture and replicate many of the city's most precious and unique objects ( Yet another win for 3D-Printing."
Link to Original Source

Comment: Re:Same Question for Particle Physics (Score 1) 358

by Landak (#37235844) Attached to: Ask Slashdot: Math Curriculum To Understand General Relativity?
There's a wonderful book called "Quantum Field Theory In A Nutshell", by a guy called Zee. It's fantastic. It's also about the most concise introduction that I've found; you might also get a kick out of reading Feynman's doctoral thesis. In short, be prepared for a whole bunch of Lagrangians (or, more precisely, Lagrangian Densities) and proofs that you see once, scream loudly, and then forget about. I don't know how much understanding of quantum mechanics you have, but you need an awful lot of it, specifically Fermi's Golden Rule. Again, as a mathematician you'll find this easier than perhaps most. I can recommend this book as an introduction to quantum mechanics, which starts from a knowledge of linear vector spaces in the Dirac notation. After that, Zee (and many, many glasses of whisky) will get you the rest of the way (inasmuch as there is a 'way', or anything at the end of it). The Higgs mechanism in particular is beautiful. You don't need to remember your curvilinear coordinates very well, but Lie algebra is vital. The trouble with particle physics is that a lot of it is phenomenological -- you'll find High Energy Physics, by Donald Purkins a very good introduction to the experimental side of it, and that side is important. Good luck!

Comment: Roughly speaking, learn maths. (Score 1) 358

by Landak (#37235802) Attached to: Ask Slashdot: Math Curriculum To Understand General Relativity?
First off, you don't state how much knowledge of maths and physics you _actually_ have beforehand, This makes answering the question an awful lot harder -- a 'college course in calculus' could be evaluating simple derivatives, or it could be some nasty vector calc and differential equations. In the order that they come into my head, you need to understand _intimately_ vector calculus (leading to Einstein notation -- play with it and become comfortable with it!), methods of solving partial differential equations, multivariate calculus, and how to properly play with differentials (i.e. proofs that start with statements like "df(x, y) = \partial f / \partial x dx + \partial f / \partial y dy"). You'll also need to properly understand matrix algebra, and ideally what tensors are (hint: generalisations of matricies that follow certain properties). You should be able to prove vector identities in Einstein notation, and be quite comfortable manipulating 'hardcore maths'. Honestly, just go away and play with maths until you understand it fully, you understand where it comes from, and you can use it without thinking about it at all. After that, try and become familiar with special relativity. This will be hard. Feynman explains everything very well in his lectures, but he doesn't list any problems: the best way to learn physics is to derive a true statement (like the lorentz contractions) and go away and shove it in all sorts of different situations (i.e. answer problems with it). The book by French & Taylor is commonly well-received; there are many different textbooks. Find a good set of problems, and answer them. Then, when you understand modern Special Relativity, get a large GR book -- there are many; Gravitation, or "General Relativity for Physicists" is a good one -- and read it. _Think_ about it, and answer the problems at the end of every chapter. If your book doesn't have questions at the end of each chapter, go away, and get one that does. Make sure you do them, and if you don't get something, find out why. If you can't find out why, ask someone who can. Finally, a taught undergraduate level course in GR would be a fantastic introduction after a well-defined amount of knowledge has been acquired. The lecture notes from the course at my home institution can be found here.

Comment: Classics Online (Score 1) 228

by Landak (#33120726) Attached to: String Quartets On the Web?
Classics Online, owned by the decidedly non-RIAA Naxos label, is by far the best source I've ever found. Not only do they have *everything* from Anonymous Four onwards, but they're not Evil, don't have any DRM, give away a free track a week, and frequently have "samplers" of composers you'll never have heard of, where you get ~20 tracks for £2/$2. I'm not affiliated with them, but I am a rather satisfied customer.

Comment: Shiira (Score 1) 189

by Landak (#33020964) Attached to: Firefox Tab Candy Alpha
The OS X-only, Webkit based (japanese) browser, Shiira, has had this "tab-sposé" feature for years. It was written during a period when Safari "showed promise" but was nowhere near properly usable, but doesn't appear to be well maintained at the moment, which is (imo) something of a pity.

Comment: Re:Why haven't we evolved to see IR or microwave? (Score 1) 238

by Landak (#32850954) Attached to: Some Birds Can See Magnetic Fields
Evolution doesn't particularly care if something is good, just if it is "good enough". We've evolved to the great humbling oafs that we are now throughout a variety of intermediate stages -- but all of them have something in common: we've been on earth, and, it is believed, underwater. Let me just show you two graphs; one of the measured absorption coefficient of water (beware the axes: it's a semi-logarithmic plot), and, secondly, the absorption spectrum of the atmosphere. If you look at one and then the other, you'll see that the only window where both materials aren't as clear as the reason for Jar Jar Blink's conception is roughly the range ~300-~1000nm. This corresponds to what we dub "the visible spectrum" and is the part of the EM spectrum where the vast majority of life on earth is either pigmented or sees -- where "the sun is brightest", as most of the light from the sky is reaching the environment in which organisms live (aquatic or not). It also roughly corresponds with the peak of the Sun's blackbody spectrum. When you consider that we can measure light from all over the universe coming to us in wavelengths ranging from the tens of metres to less than a tenth of a fermi [femtometer], you have to concede that we really are a product of our environment. Oh -- and IANAL, IANABiologist, but I am a biophysicist :-).

Comment: How long will Digital Britain last? (Score 5, Interesting) 130

by Landak (#32290980) Attached to: London's Mayor Promises London-Wide Wireless For 2012 Olympics
To the joy of nerds everywhere in the UK, it seems like the Digital Britain bill might not last very long with the current Government.

Whether or not Cameron and the conservatives can splinter away from Murdoch enough to let this happen remains to be seen, but I am currently naive enough to be genuinely optimistic about the results of having liberals in power for the first time in over a century.

Comment: Musicians (Score 4, Interesting) 257

by Landak (#31880592) Attached to: Research Suggests Brain Has a 2-Task Limit for Multitasking
What about professional musicians, who have to concentrate on far many more things than two at once? Organists, in addition to playing anything up to five keyboard manuals with their hands and one with their feet (simultaneously reading anything up to twelve lines of music, though in practice usually never more than five), have to listen to a choir and/or congregation, watch a conductor, and read the music, all at the same time. Some of them can even sing competently one line whilst doing so!

Whilst I can accept that it is very difficult to consciously concentrate on more than two things at once, somehow some people can train their subconscious into doing so -- when sight-reading music, I experience a lovely sensation, almost as if my brain is being "split" down the middle -- if I concentrate for too long, I start to develop a headache and feel exceptionally exhausted. It is a most wonderful feeling, and nothing else in the world quite comes close (although doing some rewarding mathematics isn't far behind). I would not be surprised if it were possible to find many more examples of people concentrating on more than two things at once, "simply" through getting other bits of their brain to do the dirty work. Juggling on a unicycle while jumping over a skipping rope, anyone?

+ - iPhone Could Be Banned in Europe-> 1

Submitted by
Pieroxy writes "After numerous reports of iPhones exploding in Europe, the authorities have warned Apple that they could just ban the phone from the European market. While this sounds a little far fetched for a handful of "explosion" reports, the message is clear. What is more pitiful about this whole story is that most if not all of the explosions cases are clearly fakes. How could an iPhone explode enough to break its glass plate, but not enough to actually damage the screen? (Yes, some people claimed an explosion while they still had a functional device)"
Link to Original Source

At the source of every error which is blamed on the computer you will find at least two human errors, including the error of blaming it on the computer.