Geek stuff – Page 112 – a sibilant intake of breath

Mnemonics for Pi

The people who memorize thousands of digits of pi generally strike me as more inhuman than impressive – not at such tasks does the normal human mind excel. Nonetheless, being able to recall ten digits or so might allow you to win bets at geekier parties and, if that can be achieved painlessly, it may be worth doing.

Probably the best way to do so is with mnemonic techniques. You can get fifteen digits by using the number of letters in each word of the following phrase:

How I want a drink, alcoholic of course, after the heavy lectures involving quantum mechanics!

Many other examples, including an entire sonnet, are on the Wikipedia page for Piphilology.

The Dark Knight

Ordinarily, comic book movies are an exercise in the aggressive non-suspension of disbelief, for me. Whether internally criticizing absurd physics or ludicrous plot points, I generally entertain myself more despite them than through them. The Dark Knight was an exception.

I posit two major reasons for this. Firstly, it is a result of the character of the Batman universe. It exists at a larger scale than many fictional or comic universes and, as such, has more freedom to establish its own rules and expectations. It is much more Lord of the Rings than Spiderman, despite greater superficial similarities with the former. Gotham City simply differs enough from our world to make it a clear allegory, rather than reality with implausible supernatural additions and equally implausible smoothing over of plot progression (How do characters put things in place to appear at the middle of chaotic chase scenes? How does the Joker recruit and train people? Why can everyone use unfamiliar equipment instantly? Etc.) It takes a pretty good film to suppress such questions in my mind, and this one manages it notably well.

The second is simply that the acting and presentation are quite compelling. The over-the-top action sequences are less asinine than in many smasher films, and there are some decent character and thematic issues addressed. Probably more importantly, the film has a powerful aesthetic – one that even a fairly reluctant appreciator of alternative universes can respect. Where the later X-Men films felt tacky and emotionally overdone, the gritty and chaotic Batman style remains stubbornly consistent.

Of course, Batman’s moral code remains ludicrous. Simply refraining from actually killing people immediately and with your own hand seems like a bizarre form of self-limitation, when you are perfectly happy to set off massive explosions and otherwise indirectly kill large numbers of people. The film isn’t entirely divorced from point-scoring on contemporary political issues (such as the security value of mass surveillance), but it wears such garments in an accessory fashion, rather than serving as a vehicle for polemic.

On a side note, the film demonstrates the degree to which Hong Kong is itself an alternate universe, at least as viewed from the air. The place looks like Ghost in the Shell made flesh, and provides an almost visceral reminder of the rise of Asia – one that the upcoming Beijing Olympics will doubtless reinforce.

The only question on renewables is when

One of the most active debates within the environmental community is how much of our energy we should be getting from renewable sources in the near to medium-term. There are those who assert that it is too scarce or intermittent to provide more than a small share, thus making things like nuclear fission and carbon capture and storage necessary. Then, there are those who assert that with more efficiency and a better grid, we can move to a renewable-dominated grid within the next few decades.

Ultimately, it seems important to remember that the only real questions on renewables are ‘which ones’ and ‘when.’ By definition, we cannot keep using any other kind of power indefinitely. Furthermore, there is good reason to believe that renewables will soon be a more desirable option overall, even when fuel scarcity and climate change are not taken into account. Both questions have their technical sides: the relative appeal of different options depends on technology, funding issues, and physical circumstances. Both questions also raise issues of preferences and fairness.

Yes, there is a danger of moving too quickly and suffering from early adoption problems and the later emergence of superior technology. There is also, of course, a danger of falling behind and suffering from dependence upon energy sources in decline. Striking the right balance requires good engineering, good policy-making, and the vision to build a better world.

Knickbein

During the Second World War, the German air force used a system called Knickbein to guide bombers to targets in Britain. Essentially, it consisted of a two radio beams which the planes could fly, allowing them to drop bombs on blacked out cities, deal with bad weather, and otherwise manoeuvre accurately. The beam to one side broadcasts ‘dot’ signals, while the other sends ‘dash’ signals. Hearing a continuous tone means you are in the middle. Hearing one or the other tells you to divert your course somewhat. Intersecting beams over targets told pilots where to drop their ordinance:

Estimates of the accuracy of the Knickebein suggested that it was capable of putting a 300 m x 300 m box around an intended target, which when saturated with bombs from a mere 40 aircraft would put the bombs down on average 17 metres apart.

The beams were 400-500 metres wide and were in operation (at a frequency of 31.5 Hz) as of 1940.

The British came up with progressively more sophisticated means of blocking the technology. Operation ‘Headache’ sought to jam the beams using radio chatter, itself produced using “modified hospital electro-diathermy units used for cauterising wounds.” Later, more sophisticated approaches were employed. According to David Khan, the British were eventually able to ‘bend’ the guidance beams using transmitters of their own, causing bombers to “unload most of their high explosive… into empty fields and the Channel.” A jamming system used against the more advanced Y-Geraet system in 1941 apparently prevented 80% of bombers employing it from dropping their bombs at all, as they were prevented from getting accurate ranging signals.

No doubt, dramatically more advanced systems and countermeasures exist today, in spite of the existence of cheap and accurate satellite-based positioning technology.

Who are you really talking to?

Bruce Schneier has an interesting post about man-in-the-middle attacks. These are situations in which party A and party B are trying to exchange sensitive information privately (for instance, credit card numbers or orders for moving hostages) without realizing that party E is in between them, pretending to be party A to party B, and vice versa.

The attack model has been mentioned here before in the context of cellular phones. It is rather more interesting in the context of the Betancourt rescue from the FARC.

Dyed panels for concentrating solar

A team from MIT may have developed a cost-effective solar collector system for buildings. It consists of panes of glass coated with particular dyes. Each pane collects light in a specific range of wavelengths and delivers it to a relatively small area of solar cells. As such, the technology would replace some relatively expensive photovoltaic components with cheaper glass ones. It would also do away with the need for moving sun-tracking mirrors.

As with many human innovations, there is a natural precedent. Photosynthetic pigments in chloroplasts help to capture the light used in photosynthesis. They too differ in colour depending on the peak wavelength being targeted, thus explaining why you can have your algae in red, brown, yellow-green, etc.

Getting VOIP phone numbers

Voice over internet protocol (VOIP) is a way of sending and receiving telephone calls over your internet connection. At its best, it means not having to deal with local fixed-line telephone providers at all. It is also cheaper and more versatile than a conventional phone and offers possibilities not normally available, such as having local numbers all over the world that you can access from any internet connection, as well as things like having your voicemail messages emailed to you.

Those waiting for SkypeIn to be available in Canada do have at least one option of comparable price:

Get a router with SIP based VOIP functionality. (For example, the Thomson ST780 sold by Teksavvy.)
Get Canadian Direct Inward Dialing (DID) numbers from someone like Voip.ms. These cost $2 per month each, and are available for a great many different areas. You can also get numbers in the US, UK, or elsewhere. Many numbers can be used seamlessly with the same phone and voicemail system.
Get a free account with MySIPswitch.com.
Have that free service configured by someone who actually understands how it works (not me).
Configure the DIDs to point to MySIPswitch
Configure your router
Plug a phone into your router. It will now receive calls from any of your DID numbers, and can also place calls anywhere in the world at low rates.

Sure, a pre-packaged system of the Skype or Vonage variety would requires less tinkering. That said, the approach above works right now, and costs very little to boot.

Improv everywhere

The internet creates the possibility of organizing amusing mass pranks. Improv everywhere (who have done some funny things in the past) came up with a clever idea employing twins and subway cars.

Both of my brothers did improv of the more conventional on-the-stage variety. These sorts of surreal social experiments don’t require creative skill on the part of the performers, though they do produce entertaining bafflement among passers-by.

Mutating Scrabble

As it stands, I think that Scrabble favours spatial and numerical abilities a bit too strongly, while not doing as much as it could to highlight and exhibit vocabulary and anagramming skill. In response, I propose two minor rule changes, one fairly trivial and one much more game-changing.

First, when a player has a word challenged, it is necessary that they be able to provide a correct definition for it, as well. If the word is in the chosen dictionary and they are right about what it means, it remains on the board and the challenger misses a turn. If the word placer fails either test, they must take back the tiles and forfeit their turn.

Secondly, double and triple word and letter scores are disregarded. This makes creating long words with rare letters more valued than normal.

A fair bit of experimentation will be required to determine whether these rules actually improve the game in the manner desired. Thankfully, there should be a fair bit of scope for that, since Emily and I are now equipped with a board.

Bletchley Park today

Bletchley Park, the English manor where codebreaking was undertaken during the Second World War, has been falling into disrepair due to lack of funds. This seems especially ungrateful, given the extremely important role the signals intelligence developed there played in the war. In particular, the decipherments helped to clear the Atlantic of U-boats, keep the United Kingdom supplied, and eventually shift the people and equipment required for D-Day and the retaking of the continent.

Work done at Bletchley was also important in relation to the emergence of modern computers. If there are historical sites worth preserving, this is surely one of them. Thankfully, the Heritage Lottery fund now seems likely to provide funding.

The fact that the codebreaking work done at Bletchley was not publicly announced until the 1970s makes it doubly important to tell the story well now. For decades, people who worked there had to respond with awkward silence when asked how they contributed to the war effort. Their extraordinary contribution deserves to be well marked today.