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Stu Savory's Blog
An auld Scot blogging in Germany
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Saturday, February 26, 2005
Grief Oor hoose, it is sae empty noo An' silent as the grave Ma hairt it greets an' weeps sae sair, An we ha'e naught tae doo.
Ma hairt is bare an' bleakit too Wednesday, February 23, 2005
Tuesday, February 22, 2005
Persona Non Grata'W' is coming to Germany to visit US troops here tomorrow. Probably the least liked person in the world, let's face it, even most Americans didn't vote for him (49% of those who voted plus all the non-voters). And now we've got to put up with the scaramouch. The inconvenience which that involves! Exaggerated security, lest someone top him ?Dubya must be one scared guy! : The whole route Dubya travels is being made into a one-way system, all around the cities of Frankfurt, Mainz and Wiesbaden; even the Autobahn closed on one side. So people can't get to work or get home properly. Opel is stopping car production in Rüsselsheim wednesday because they can't be sure all the production-line personnel get in to work. Well, Opel is owned by GM; I wonder if GM realise the loss (750 cars) is directly caused by Dubya? 100 busses along his route, trams and trains cancelled; it is said that Hitler made the trains run on time, Dubya can't even do that. Miserable failure! People who live on Dubya's route, e.g. between Wiesbaden-Erbenheim and the US airbase there must park their cars elsewhere and move their garbage cans behind their houses, lest there be a bomb hidden in one. Linde, Nestle´ closing for the day, Werner & Mertz GmbH too. The latter make shoe cream for guys like Dubya who polish their shoes (the German word is Wichser ;-). Rumour has it that even the mobile phone net will be turned off locally there, lest someone use it to trigger a bomb. Even the manhole covers are being welded down! A million people inconvenienced :-( I expect that Dubya will make a stump speech, or will he try honesty? "We have become a Nazi monster in the eyes of the whole world--a nation of bullies and bastards who would rather kill than live peacefully. We are not just Whores for power and oil, but killer whores with hate and fear in our hearts. We are human scum, and that is how history will judge us . . . No redeeming social value. Just whores. Get out of our way, or we'll kill you." No, that's not Dubya's stump speech. He's not reality-based. Nor are they my words. The quotation was written by American journalist Hunter S. Thompson who committed suicide yesterday, by putting a bullet through his own gonzo head :-( At least he will be sadly missed. Just in case you were curious about today's initial, the colour of 'W' is an unsavory braun :-( Monday, February 21, 2005
Getting chin deep into Chocolate Moose ;-)ObDogBlog : Over at Just My Opinion Jen tells us amusingly about her dog begging for food. So I told her that my bitch likes getting her chin into a Chocolate Moose. I bet she thought it was both impolite AND a spelling mistake, and the rest of you blogreaders probably did too ;-)
Sunday, February 20, 2005
Maths TroublesPoor old well-intentioned Gary Williams reported from Mathworld Headline News that the 42nd Mersenne Prime has (probably) been discovered. Unfortunately the HTML SUP and SUBs didn't transliterate correctly, so poor Gary showed the formulae wrongly. I sent him the HTML for an example correction (which renders correctly in Opera 7.54u2), but his comment box won't accept the formulae I tried to send, so I'm showing them here.Upon further inspection, it turns out that Gary's source, Wolfram Research's MathWorld even gets the mathematics wrong! :-( They omit to mention that the power factor of a Mersenne Prime is by definition itself prime and so even give a number of wrong examples N=15, 63 etc. A Mersenne prime is a Mersenne number, i.e., a number of the form M=2n-1 which is prime. In order for M=2n-1 to be prime, n must itself be prime, and not 15 (=3*5) or 63 (=3*3*7) as they gave as examples. For composite n with factors r and s, we have n = rs. Therefore, M=2n-1 is M=2rs-1 , which is a binomial which always has a factor 2s-1 and so is NOT prime (Q.E.D) But thanks for the heads-up anyway, Gary! Robin has maths troubles too, she writes "I wanted to place objects (let's say small circles) around the circumference of an ellipse so that all objects were equal in size and had their sides just touching one another. How do I know what size the smaller objects need to be?". Now it is obvious that this cannot be solved with just a straightedge and a compass (Euclid's toolkit), so I won't bore you with the proof thereof ;-) And David wants to know how far the Earth goes in 1 year (i.e. one orbit around the sun). Both of these questions imply knowing how to calculate the perimeter of an ellipse (all orbits are conic sections, closed orbits are ellipses, David). Unfortunately, although we know that p=pi*d for a circle,
There is no simple exact formula
for the perimeter of an ellipse :-(
There are simple formulae which are not accurate, and there are
accurate formulae which, however, are sadly not simple.
Way back in 1742 McLaurin was the first to give an accurate formula :-
Those same Mathworld folks give the approximate formula, which is up to 10% off. There is a much better review of exact vs. simple formulae given by Dr. Gérard P. Michon online so I won't write it up myself since his (longish) summary is much better :-) Friday, February 18, 2005
TGIF : Your Feedback during this weekLead InSarah (UK) tells me that the Brits have lost 30Kg Plutonium from Sellafield. Dividing by the critical mass of plutonium, I calculate that's enough for at least 7 A-bombs. Kinda iranic, huh ? Danger from Web-prowling paedophiles? :-( Bits for Bikers , Booklovers and Beta-function Bloggers : Maestro musicians : The Meme of Dorian Gray : Best of my Blog 2004 :
Wednesday, February 16, 2005
The Meme of Dorian GrayYesterday an old photo of me - one of only 3 childhood pics - fell off the wall. The glass broke and tore the photo :-( Remembering Oscar Wilde's narcissistic tale The Picture of Dorian Gray, I rushed to a mirror and yes, all of a sudden I've grown old, depraved and debauched ;-)Quoting Wilde from "Lady Windermere's Fan" : "Men become old, but they never become good." To cut a long story short, I went through our 25 analog photo albums looking for a replacement. Here's a dozen Dorian Gray snapshots taken through the past 60 years (mouseover for dates)
So I take this opportunity to start a new meme for you blogreaders. Post a similar gallery of photos of yourself taken at (say) 5 year intervals from birth up to today and see if your Dorian Gray portrait got torn too ;-) Mail me the permalink of your Dorian Gray post, put the permalink to this blog entry on your posting and I'll link back to your Dorian Gray post here. It'll be sort of like the Skyline Meme we did in september and october last year, but more egoceIntric*. Bloggers in the Dorian Gray meme
Bummer : I guess my parents didn't have a camera, I could only find those 3 B&W photos, and even later there are leaps of a whole decade. Only with the advent of digicams are there more photos, despite the fact that we have 25 photoalbums. All those analog photos are of other people and other places; I guess I was doing the photography which is why I was never in the shots. BTW: I'd scanned all the old photos years ago, so the torn one is not lost :-) Let me not forget to thank Claude over at Blogging in Paris; her blog-header actually triggered this idea; the Dorian Gray stuff I just made up when getting to the bottom of the page; a wild idea, but the serious-looking ego-photos show the importance of being earnest about this ;-) * Spelling Corrector Footnote : Words like egocentric should have an "I" in the middle ;-) Tuesday, February 15, 2005
Books recommended in my BlogPhillippa takes me to task because the webpages are very out of date on which I made book recommendations for English books [19/4/2003 :-( ] and for German books [6/2/2003 :-( ].My excuse is that I changed over to putting my book recommendations into the sidebar of this blog as cover photos. True, there were months without any such tips, but that's because I couldn't honestly recommend anything I'd read in that month; I left the gonzo stuff out. Let me compensate and save you clicking through 2 years of blog by showing the covers again here, a mouse-over will display the titles and authors. The order is roughly chronological and I've removed my links to amazon.de because most of you will go to your own bookstores.
I'll stop here at 50+, although I have about 6 to 7000 other books here at home too ;-) Monday, February 14, 2005
Valentine's day :-) :-) :-)
Valentine's day has become so commercialised that the EU have now issued an international icon for Valentine shops :-) But without all the commercial crap, I'd like to say thankyou to dear Cornelia, who has (for some reason) stayed with me now for 26 years. Love you, lass! There may be some perfect partners out there* who have never forgotten an anniversary, a birthday or Valentine's day. I which case let me tell you what it's like. It's like the house flooding 9 inches deep** in icy cold water, which you have to wade through barefoot, before climbing up a metal ladder*** to bore a hole in the ceiling for a hook to hold the noose to hang yourself by ;-) And while you're standing in the gathering dusk with wet bare feet on this metal ladder in the water using an electric drill whose worn cable droops through the water, she takes a shocking flash!!! photo, just to prove to eternal posterity what a complete idiot you are! Footnotes : Sunday, February 13, 2005
Sundry Sunday SinsWent to a folksingers' cafe´ in the nearby city friday and heard an old friend, scottish folksinger Paul Joses performing. Reminiscing together, we think it's been about a decade since we last did a gig together, so for old times sake we're planning to do a gig in nearby Lichtenau on 22nd October this year. This is sufficient advance warning for y'all to buy earplugs ;-) Paul's latest CD is named "Calling the Boatman". Apropos boatmen, I wonder which of their seven toasts the Royal Navy will use now that Charles and Camilla are getting knotted? They'd have a problem using the Saturday toast, eh? I think it's more likely to be the Wednesday toast :-)Today of course we are remembering the 60th anniversary of the fire-bombing of Dresden, revenge for Coventry. So have mushrooms for your first meal tomorrow, as Kurt Vonnegut (who is the author of inter alia the Dresden fire-bombing story Slaughterhouse Five) would have done if he'd used a spelling corrector (i.e. Breakfast of Champignons ;-) Whilst on the subject of war crimes, Donald Rumsfeld showed up in Munich yesterday. That's just 2 days after a German court declined to prosecute him for war crimes, claiming the weak excuse that "the US courts are responsible". More like irresponsible, I think. But I'm glad to read that more and more Americans see it the same way I do. Rumsfeld (and Rice, last week) are calling for more unity between the US and the EU. That's simple to achieve, Donny Boy, just withdraw all your troops worldwide into the lower 48 and make everyone happy :-) Saturday, February 12, 2005
New web laws pending in GermanyOur government is cracking down on spammers and phishers. New laws are being passed which e.g. make it a crime to manipulate mail-headers with a view to misleading the recipient. Also any advertising mail (spam) has to be identified as such [ADV]. Furthermore, all websites have to have an easily-found Impressum page which gives the real name and address of the owner. This is an anti-phishing measure and is trying to stop crooks from dealing anonymously. Blogs may not be anonymous!What is new is that all pages of a web-site (and a blog) have to contain a direct link to the Impressum page (it must be only 1 click away from anywhere on your site). The law applies to private sites too! The link must be labelled Impressum too, not 'contact' or 'about' or anything else. So, to comply with this I've just discovered that this website has 342 pages, ca. 60% in German, 40% in English, and I've had to update ALL of them to point to either the German or English Impressum page. Generally I've put the link in the bottom line of each page. Where the page has a menu of its own I've added the Impressum link into that menu. I've been cursing at these 2 hours of make-work, for which I could have used a few of Santa's little helpers (are Santa's helpers subordinate clauses?) and had to resist the temptation to start to polish all those old pages laying around ;-) I think some of them are so old they are even mentioned in my will (that's a dead give-away). I had to upload 342 pages as well, just as well I'm on broadband these days. The statistics about the 'natural' lifetime of various pages are now all shot, the search engines will have to catch up, and anyone hitting the 'what's new' button (bottom right) next week will be inundated by false impressions of activity:-( Nevertheless I think this new law is a good idea. It'll become an EU law too soon. I know that I do get annoyed at anonymous sites, such as are typical in the Near and Far East and in the US. I just wonder what the anonymous bloggers will do, hiding behind their pseudonyms? :-) Friday, February 11, 2005
Your comments this week
Not much mail this week, sparse commenting, probably due to the
quite excessively(?) geeky nature of my last three posts :-(
David & his UK classmates thanked me for wednesday's Playfair explanation with an enciphered message, which I cracked by guessing your probable word "thankyou", David. Since you asked, it took just over 20 minutes using pencil and paper only, no computers allowed. BTW you had a encoding error in line 4. Doug Alder (C) dreamt up a weak crypto algorithm in his sleep, so I wrote back 'explaining' how to break or strengthen it, to which poor Doug replied "You do realize, don't you, that I don't understand a damn thing you just wrote :-)" Ooops. Jean (C) asked about Euclid's original geometry, so I posted this for her/him. Bob Fairnie (Scotland) hae scrievet anent ma Burns Nicht poast: "If ye'd like tae register concairn anent the raicent foonderin o investment plans for the Burns Cottage an Museum, ye can sign an epetition tae be ludged wi the Scottish Pairlament. Gaun tae Burns Petition." Pierre (F) read monday's closing pun and sent me the animated gif on the top left of today's blog-posting, so I "could have a slide rule". Viewing your animated gif, Pierre, I have to complain that I spent a lot of money on a 3-D graphics card, but my otherwise-great 2-D-only picture-viewer (Irfanview) can only flip left-to-right and top-to-bottom but not back-to-front :-( He also suggests another do-it-yourself lazy solution to monday's apocryphal "clock-tower" anecdote. "The clock tower in your photo appears to be made of red brick (City is/was a redbrick university, right?) so trade the barometer for a good pair of binoculars and use them to count the number of bricks up the tower, then multiply by the brick size ;-)" C'est bric-college, Pierre ;-) Wednesday, February 9, 2005
The Playfair CipherYoung David and his schoolmates go to school in Edinburgh (Scotland). They asked me (again {oops, my bad}) to post something easy about the Playfair code, so here it is, boys.Back on December 22nd 2004 I showed you
how to break cryptograms. That is easy to do because one letter consistently replaces another.
Even if the blanks were omitted one could do what is called a frequency analysis. That means counting the relative
frequencies of the enciphered letters. The most frequent probably represents "E", the most frequent letter in the english language.
The relative ranking of the letters in English is "ETAOINSHRDLU...",
which, by the way, is not just by chance also the layout of the letters on a So we need to get away from the restriction that one letter consistently replaces another.
One way to do that is to use letter pairs. That way we get an
effective alphabet size of 26*26 = 676 symbols (letter pairs)
instead of just 26, thus making frequency analysis harder to do.
This is how the Playfair cipher works. Choose a keyword or (better)
a key phrase. Let's choose The white queen jazzes Alice almost daily.
Write this phrase in a 5 by 5 square (letting J and (say) Y be considered the same letter).
If a letter occurs more than once omit it all but the first time. Finally,
append any letters as yet unused. Thus we get :-
Now let's see how we encipher a message with this keysquare using
the historical example
"LTKENNEDYCOMMANDEDTHEPTONEZERONINE" (Lt. Kennedy commanded the
PT109, which was a type of patrol boat in WW2).
There are four rules used in encipherment of letter pairs :-
Now how are the letters encoded? Writing the ciphertext in beneath the plaintext, we get :- The receiver uses the same key-square to decipher the ciphertext.
He also uses the same four rules, except that "below" is replaced by
"above" in rule three, and "left" replaces "right" in rule four.
So ZE RT AR... becomes "LT KE NX..." . Finally the
superfluous Xs are stripped out by inspection and in the fifth pair he
has to decode the FU as either DY or DJ depending on context.
That was straightforward Playfair, but there are some
things one can do to make it more cryptologically secure.
We added the missing letters B F G K P R V X into the key-square in
alphabetical order. This is not a good idea (ordering is generally a bad idea).
Agree on some other rule to add them.
The main problem though is that adjacent plaintext letters
correlate in natural languages, so we need to get rid of the
correlation. One way to do this is called striation.
This means making plaintext-pairs which were well apart in the
original message, typically 5 or 6 letters apart. Writing the original message
in groups of 6 letters under one another we get
But yes, David, Playfair can be broken, particularly easily if you can
guess probable word(s) of the plaintext. Then it just 'falls apart' if
you are a practiced codebreaker :-)
Now a little history. I used JFK in the example because
he used Playfair in WW2. The boat he commanded, PT109, was rammed inadvertently(!)
in the night by the japanese destroyer "Amagiri", sliced in half, and sank.
Kennedy and his surviving crew swam to Plum Pudding Island.
From there they radioed the following message :-
Now a little more history. This cipher is attributed to the wrong person!
It was actually invented by the British inventor Charles
Wheatstone, he of the Wheatstone Bridge for measuring electrical resistances.
Lyon Playfair, the first Baron Playfair of St.Andrews, was a good
friend of his; they even looked very much alike (short and
bespectacled). Playfair had much better political contacts though, and
was able to demonstrate this system to Lord Palmerston (who was Home
Secretary at the time) and to Prince Albert (Queen Victoria's husband).
Although the Admiralty rejected it, the British Army used this cipher
in the Boer war and in WW1, referring to it as the Playfair cipher.
Given only pencil and paper and no computers, it is in its
striated form a pretty good cipher, as long as the messages are kept fairly short.
Finally David, I know you go to school in Edinburgh. There are
several steep steps and alleys leading up the hill to the castle.
If my memory serves me correctly, and it usually does, one of these
narrow passages is called the "Playfair Steps". Same man, David,
same man :-)
Now folks, go have fun with this cipher but don't use it
for real, 'cos I (and others) can break it!
Monday, February 7, 2005
Old Geeks [ with a B.Sc (Hons) in Physics ]
Physicists are geeky, especially we older ones.
Thirtynine years ago a number of us read Physics at City University
(London, UK) and we are now trying to contact all our classmates for a
40th graduation reunion next year. So get in touch, any classmates, mail me please!
Here's the ultimate geeky physics student story. The professor is good on theory, but short on practice. He set an exam question "Given a barometer, determine the height of City University's clock tower". He expects us to know that atmospheric pressure drops about 1 millbar every 26 feet of altitude at sea level. Thus a measured difference of 3 mb would show the tower to be 78 feet high. In practice, you can't read a barometer to better than ½ mb accuracy, implying +/- 13 feet on the measurement, or +/- 17%. We decided to show him some more accurate alternatives and criticise his theory-heaviness simultaneously ;-)
The photo at the top of this blog-entry belongs in the class of physics-memorabilia. It is a photo of the actual blackboard as used by Einstein in 1937 while lecturing at Oxford on relativity :-) And here's a question for the older geeks, like Frank Paynter, Joel Sax, Doug Alder or Betsy Devine : Have you noticed how nowadays these young geeks all wear slavering supercilious smiles whilst doing their calculations on the newest pocket-PCs? We older geeks never smiled or slavered or even use desktop calculators, we just did OUR calculations with sly drools :-) Friday, February 4, 2005
Your mails this week
Well I must have been doing something right in January because
blog traffic increased quite a bit, albeit with the usual strong
weekday variations. Don't know what the cause was though.
Last week there was quite a little feedback (and that was mostly
from regulars).
As regular blogreaders will know, on fridays I post your feedback
emails...
Anna Pashen has set up an Orkut group 'Slave Labor Graphics'. Jane points out that I've been screwing up the February permalinks. Ok now, Jane? Funny Canadian blogger Doug Alder liked my January posting about recursion and writes that his favourite example of this type of recursion is The Infinite Cat Project. Doug is also a Biker, and replied to tuesday's dedicated Biker Joke with this comment:- To your joke I would add one of the best bumper stickers I've ever seen was the word MOTORCYCLES in very large bright yellow type on a black background. Each letter was split in half and running down center between the halves, in a small font, was the phrase ( in white so it would stand out) - Biker in spe Rob writes "I would really enjoy rebuilding a bike"; well Rob, the guy to go to in north CA for parts and advice is builder Art Sirota (Palo Alto, AFAIK) whom I had the pleasure of meeting one whole day. He's the guy who wrote/sings "The Norton Songs"; go buy the CD! Theo could remember only the punchline of a joke The lady said 'Hell no! Get your own monkey!' and asked for any jokes with that punchline, so I sent him this topical one :- Hell no! Get
your own damn monkey!
US reporter lady talking to Iraqis at their polling station. She asks "Who are you gonna vote for?" An Iraqi replies "Can we vote for Bush?" ... you have the punchline already, Theo ;-) My friend Jimmy MacCarthy liked my short history of Scots poetry and replied in ilka leid :- I likit yer ain list o Scots poetry nae a bad collection at a' Ye'el hev tae print mair anither day! I wis gled aboot yon Hugh MacDiarmid wirds (MacDiarmid wis a great chiel) Lek yersel ma favourite poem is e 'The Drunk Man looks at the Thistle.' No wan in fifty kens a wurd Burns wrote But misapplied is abody's property, And gin there was his like alive the day They's be the last a kennin haund to gie - Croose London Scotties wi their braw shirt fronts And aa their fancy freens rejoicin That similah gatherings in Timbuctoo, Bagdad - and Hell, nae doot - are voicin Burns' sentiments o universal love, In pidgin English or in wild-fowl Scots, And toastin ane wha's nocht to them but an Excuse for faitherin Genius wi their thochts. O Burns hissel I lek 'A Parcel O' Rogues' Rebecca points me to some excellent book reviews (kinda long though)
by Tony Judt entitled
"Europe vs. America". These 3 online reviews are well worth
reading, and illustrate why we Europeans are troubled by the current US
administration (and
vice versa of course.) A whole number N is divisible
by any composite number C, iff it is divisible by
ALL of C's (perhaps powered) prime factors.
Anonymous from the US (left nameless for politeness sake) came searching (unsuccessfully) for "test of divisibility for 15". I only list divisibility tests for primes (below 50). 15 is a composite number; 15 has prime factors 3*5, so a number is divisible by 15 if it is divisible by 3 AND by 5. Get the idea? Another example : 28424 has prime factors 23*11*17*19, so a number is divisible by 28424 if it divisible by 19 AND by 17 AND by 11 AND by 8 ( = by 2 THREE times). All clear now? Young David reminds me that I promised to blog about The Playfair cipher. Sorry, will do, David. A UK blogreader Elisabeth ( not HM, surely?) claims over 50% of bloggers are on broadband now, so why don't I add more pictures? Well I'll be doing that this month, Liz, as you saw already. We'll see how it goes, if dialup readers complain, I'll go back to more text, that OK? Tuesday, February 1, 2005
Jinba IttaiToday's blog-entry is for the Bikers amongst us and for a californian friend playing with the idea of getting a motorcycle. It doesn't have to be a $150,000 dollar jet-engine powered 320 hp beast like Jay Leno's. In fact it's better to start with at most 50 hp, IMHO. I say that having been a Biker for 45 years and having dropped it thrice :-(The most important thing of course is to have good gear : helmet, boots, leathers, gloves etc, Clarification of today's headline : "Jinba Ittai" is a japanese expression which I would translate as 'Rider and steed melt into a single unit'. It is the secret of riding well. That and dedication. So here's Hans-Juergen's favourite joke about a dedicated Biker, cast away these ten years on a desert island. One day he sees something approaching his tiny island. He sees it's not a ship, nor a raft. It turns out to be a beautiful blonde in a figure-hugging neoprene scuba suit. She comes ashore, and eyeing his hungry eyes , says "How long since you've had a cigarette?" and takes a pack from a waterproof pocket on the left calf of her neoprene suit, proffering it. "Thanks, I haven't had a good smoke for over ten years", he replied gratefully. "And how long since you've had a good whisky?" she says, and takes a silver flask of pure single malt whisky from a waterproof pocket on the right calf of her neoprene suit, proffering it. "Wow! Thanks, I haven't had a good Scotch for over ten years", he replied, even more gratefully. "And how long since you've had some REAL FUN?" she says, slowly and lasciviously unzipping her neoprene suit all the way from her neck to her thigh. "Wow!" replied the dedicated Biker, "don't tell me you've got a motorcycle in that thing!" |
Dr. Stuart Savory, who is an overeducated, scottish multilingual Ex-Pat,
blatently opinionated, old (1944-vintage), amateur cryptologist,
computer consultant, flying instructor, bulldog-lover, Beetle-driver,
textbook-writer, long-distance biker, blogger and webmaster living
in the foothills south of the northern German plains. Not too shy to
reveal his true name or even whereabouts, he blogs his opinions, and
humour and rants irregularly. Stubbornly he clings to his beliefs,
e.g. that he's not really evil, or even anti-american, in spite of
Dubya's efforts to convince him that he should be. ;)
Political compass Economic L/R: -1.62 Liberty/Authority: -2.56 Blogs that I read Alembic Betsy Devine Blogging in Paris Bouillabaisse Doug Alder Easy Bake Coven Elaine Kalilily Frank Paynter Jeneane Sessum Jesus' General Joel Sax Just My Opinion La Vache Qui Lit Mad Kane Making Light Mandarin Design Mercurial Old fash. patriot People's Republic of Seabrook Rude Pundit Shelley Powers TFS Reluctant Wilson's Blogmanac Yule Heibel Now Reading
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