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Eunoia
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Oh, and after the death of his old dog, Kosmo, he also has a new bulldog puppy, Clara, since September 2018 :-)
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Thursday, May 28, 2020
Homeschooling Maths : Root(2) is crazy!During this Coronavirus lockdown, parents are having to homeschool their children, sometimes in areas where they are not qualified to do so. Friends of mine are struggling to tutor their teenager in maths, claiming they were "bad at maths" themselves in school and ever since. So I offered to do the homework with the parents alone, so that they could then help the teenager do the homework. And thereby hangs this tale :-)First thing I did was to get them to self-estimate their maths abilities on Pergelator's chart :- 
They thought they might manage some algebra, but nothing more complicated. This is probably true of most parents???? The dad said he didn't even understand the homework question , claiming it said Prove that Root(2) is crazy. Neither did I, so I asked to see the homework question. It actually read Prove that Root(2) is irrational :-) So I explained that irrational did not mean crazy in this maths context, but meant that root(2) could not be expressed as a ratio, i.e. a fraction like a/b where a and b are whole numbers. Now the easiest way to do this is to assume the opposite and show that this assumption (root(2) is rational) is self-contradictory and thus wrong. So we write a/b=root(2) as the irreducible fraction (or fraction in lowest terms, simplest form or reduced fraction)
which is a fraction in which the numerator and denominator are integers that have no other common divisors than 1, so both a and b cannot be even, one of them must be odd. Now because a is even, we can rewrite it as a = 2*c. So 2*c/b=root(2). Square both sides, getting 4*c2/b2 = 2. Multiplying each side by b2, we get 4*c2 = 2 * b2, and so b2 is an even number, and thus b is an even number (as is a) too. But one of a or b must be odd, as we showed above. So the assumption (root(2) is rational) is self-contradictory and thus wrong. Q.E.D. :-) We went through this a couple of times until they could reproduce the proof reliably and were quite pleased with themselves that they could do an algebraic proof after all those years after leaving school themselves :-) And yes, I do expect teenagers to be able to produce that proof themselves. Now for some historical background, dating back to before 520 BC. Hippasus of Metapontum was a philosopher attending the school of Pythagaros. Pythagoreans preached that all numbers could be expressed as the ratio of integers, but Hippasus of Metapontum drew a square (of side 1) and looked at the diagonal in the square (root(2)). He used the proof I just showed you to discover irrational numbers. This so shocked the Pythagoreans that Hippasus was later "drowned at sea". History does not record whether this was an accident, suicide or murder for his discovery! Whatever. Root(2) is so crazy it could get you killed back then :-( Comments (2) 
Monday, May 25, 2020
Told you so!Just a week ago in this blog I opined that here (in Germany) we are reopening too soon and that this was likely to cause new Covid Infections. Sadly, I was right.In a restaurant in the state of Lower Saxony on 15th May, guests held a closed private party, disobeying all the separation and hygiene rules to be applied in restaurants. Now 18 are confirmed as infected and 118 have been put in quarantine. The landlord is likely to be fined 25,000 Euros. The restaurant has been shut down again. In Frankfurt in the state of Hessen, Christians (Baptists) crowded into their church, sang hymns loudly, thus spraying the virus around them. 107 are now infected with Coronavirus. So the Blood of the Lamb didn't work, despite what Mike Pence thinks! Way to go, Xians! A school head has publicly said that he/she thinks it would be better if all the children had to repeat a year's schooling than even one child die avoidably from Coronavirus. Nevertheless, politicians insist the schools be reopened. We'll see how that turns out :-( Now the governor (minister-president) of the state of Thuringen has decided to remove ALL restrictions (such as wearing masks in public and the 1.5 meter separation rule) claiming he is down to 133 infections per 100,000 residents. Stupidity indeed. I expect a reopening catastrophy there! Shit happens when politicians, not scientists, decide :-(
Thirsty, May 21, 2020
Fathers' Day EditionBack on the 10th of May, we had Mothers' Day here in Germany, an overly commercialised thankyou-day when the moms got a present, e.g. a new handbag.Now today, we celebrate Fathers' Day here in Germany, where young males (mostly singles) go in large groups on a hike, dragging a handcart filled with crates of beer and schnaps (=shots). Due to Corona (the virus, not the beer) this year the groups should be gone, so the beer brewers have introduced handbags for men, Fathers' Day edition :-) 
A dozen different bottles, each ⅓ liter. That's 8 pints. I'd be smashed out of my mind! Comments (3) 
Monday, May 18, 2020
Reopening too soon! Change my mind?Coronavirus is changing the world. In our country we were first shown this graph and told that strict measures were needed to flatten the curve so that our health system did not become overloaded. The measures included 1.5 meter social distancing, wearing masks when out, shutting schools, churches, large sports events, demos etc. They worked, because people followed the new rules, so the health system did not become overloaded. Other countries were less rigorous and so less fortunate.
So we are now on the green curve. Flatter but much longer. We have robust data from the outbreaks in China and Italy, that shows the backside of the mortality curve declines slowly, with deaths persisting for months. So we are probably just past the peak of that green curve here in Germany. USA and UK are still on the rising side of the curve, UK maybe peaking. But now unwary people are protesting and disobeying the shutdown. Politicians want to reopen the country asap, in my opinion far too quickly :-( 
I wish the politicians were more careful and not causing a second wave of infections by reopening far too early. They should listen to the scientists like Dr.Fauci in the USA. 
This shipwreck (below) is the impression I have of e.g. Trump's daft rapid-reopening policy. The white House has daily testing, frequent temperature checks, and daily environment disinfections. And still: Trump's valet was infected, as was Pence's press secretary, Ivanka's assistant and a dozen secret service personnel. 
Many politicians want to "save the economy" and so are reopening far too fast because they think it's all over and recovered patients cannot be reinfected (NOT proven!). Currently we have an infection rate R hovering around one, I'd like to see it consistently less than ½ over at least a month. Personally I think we will have a second and maybe third wave as suggested in the sketch below. These later waves will be bigger and will go on for longer. Note that I can't put calibrated scales on either axis, but you get the gist. 
Now shops are reopening, cafe´s too, restaurants and pubs. I regard this as highly dangerous. I only shop (masked) for comestibles/vittles etc twice a week, buying non-comestibles online. No sitting in cafes, restaurants or pubs, just take-out food maybe once a week. Nobody needs to see spectator sports live, just watch the soccer etc on TV. I'll be staying home even if barbers, physotherapists etc are open again. I'll wait until hospitals are reopened for visitors again, because then I'll know it's a scientist's decision, not an ignorant pro-capitalism politician greedy for popularity! This Peanuts cartoon summarises my present opinion succinctly :-) 
So, do you also think we are reopening too soon? Try to change my mind! Comments (5)
Friday, May 15, 2020
Out of the blue, nice hearing from you :-) ...Coronavirus is having some nice side-effects : e.g. people are more helpful and others are remembering old friends. I've emailed several to check on how they are coping in the shutdowns in their countries, and I've been getting emails out of the blue too. Thanks to all of you.First off was Gerald (D), a geocacher friend from years ago. He'd been in a second-hand bookstore where he found a copy of a (crappy) novel I wrote thirty years ago. So he bought it and sent it to me for me to sign it, which I did before returning it to him :-) So now he has two signed books :-) Then Iwan (RU) wrote that he'd be AFK (away from keyboard) and not blogreading for the next few months. He's leaving his Moscow apartment and going to live in a Datscha in the Urals (800 miles away) to avoid getting Covid-19, he wrote. I replied "Good luck if you need any medical help way out there" Out into the wild blue yonder in those backwoods. Methinks we're unlikely to meet again :-( This week, Lyn (UK) wrote to check on how we were coping in the shutdown. I've known Lyn for over fifty years now, but haven't seen her for a decade since my last trip to Oxford (for John's meeting of our old university friends). Paul (D) sent a photo of the Domiracer he is restoring; looks good! Now let's make this a shout-out to all those with whom I have lost touch : should you read this or have it forwarded to you, drop me a line to the email address below, it's nice to hear from old friends :-) Comments (1)
Monday, May 11, 2020
Good Golly, Miss Molly
Now Little Richard (a euphemism for the opposite?, which was deemed too blatant at the time) has died of cancer at 87. Thanks man, for inventing rock-and-roll! On his way down below, he will doubtless be accompanied by a chorus all shouting " A wop bop a loo lop a lop bam boo" ;-) Comments (1)
Tuesday, May 5, 2020
Learning from The Stig
The Stig's primary role was
setting lap times for cars being tested on the show, plus he would also instruct celebrity guests,
off-camera, for the show's "Star in a Reasonably Priced Car" segment. So when I saw his 2014 book, I picked up a copy and have been reading it with much pleasure. Anecdotes, often hilarious, and much driving instruction, some of which was new to me. Learner drivers in the UK get just 18 hours of instruction (for comparison, a Starbucks Barista gets 20). It's more here in Germany and less in the USA, I'm told. So this book picks up with more advanced stuff, explained better than in your run-of-the-mill driving school. The Stig's main emphasis is on smoothness, achieved by situational awareness, allowing you to anticipate ahead of time what is going to happen next. I wish I could have had this book 58 years ago! He also describes different ways of doing things, so I've been trying them out in my 1985 oldtimer, a Porsche 944, but it is difficult to break old habits, even if there are better was of doing things (e.g. I don't usually heel-and-toe). Besides being The Stig, Ben Collins does Hollywood car chases such as driving as Bond in Skyfall, Batman in The Dark Knight Rises etc. He also raced in The Le Mans 24 hour race, NASCAR, Touring Car world series etc. So yes, he is a well qualified driver AND an amusing author, despite the style-breaks :-) I just have one bone to pick, and that's with the publisher. In places, some of the book is printed in light orange on white background, which makes it difficult to read. Black on white, yes. White or orange on black, yes. But light orange on a white background is a big NO! NO! imho. I can recommend this book to other petrolheads, such as Liz Hinds' husband, who also has an old 944 , and old friend Peter (UK) who has a Porsche Boxster S and Gian in Switzerland with his old Morgan :-) Size? 288 pp. Price is about 15 Euros. ISBN is 9787-1447272847. Publisher : Panmacmillan, London,UK. Written in English, sometimes colloquial. Comments (2)
Saturday, May 2, 2020
R.I.P Wolfgang "Bulli" KloisIt is with sadness that I report the death of an old friend, Wolfgang "Bulli" Klois, who died last tuesday (28/4/2020), aged 75. He and I both worked at Nixdorf Computer AG for a quarter of a century, where he was i.a. responsible for the 8890 machine, a smaller clone of the IBM 370.
Bulli and I were friends for over 45 years. It was he who first took me parachuting, a hobby I did NOT adopt :-) However we spent many happy years hang-gliding together. The photo above shows him landing my "Adler" (=Eagle) in the winter of 76/77 after a flight from the Ettelsberg in Willingen. We've flown from the Teide volcano on Teneriffa, in the hills behind Santa Monica, and in the Alps. Later our interests diverged : I learned to fly regular GA planes, becoming a flying instructor. Bulli went into ultralights, flying around the local area. Each claimed to have had more fun :-) Now Bulli has taken that final flight, ascending as far as possible. He was 75, just two weeks younger than I am. He certainly earned his wings :-) So here am I, still stuck down here, but waving hallo in his photo taken in 1976. 
May you enjoy eternity, Wolfgang, surfing those heavenly cumulus clouds!
Comments (1)
Link to the previous month's blog.
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Recent Writings
Homeschooling Maths Told you so! Fathers' Day Edition Reopening too soon!!! Out of the blue... Good Golly, Miss Molly Learning from The Stig R.I.P Wolfgang Klois Logistic collapse soon? A story for Legba Coping with Eejitz No spit, Sherlock! Easter cancelled ;-) Sudoku challenge Summertime... Measuring Earth's size No more threesomes! The Whisky Museum Shutdown in Germany PI day Bike Shop Open Days Clairvoyance? Getting to 365.2425 days Our nearest neighbour Palindromic numbers Blogroll Ain Bulldog Blog All hat no cattle Badtux... Balloon Juice Billions of Versions... Cop Car Digby's Hullabaloo Earth-Bound Misfit Fail Blog Finding life hard? Greg Laden Hackwhackers Infidel753 Mockpaperscissors Mostly Cajun Observing Hermann Pergelator Starts with a Bang Yellowdog Grannie Archive 2020: Jan Feb Mar Apr Archive 2019: Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Archive 2018: Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Archive 2017: Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Archive 2016: Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Archive 2015: Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Archive 2014: Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec This blog is getting really unmanagable, so I've taken the first 12 years' archives offline. My blog, my random decision. Tough shit; YOLO. Link Disclaimer ENGLISH : I am not responsible for the contents or form of any external page to which this website links. I specifically do not adopt their content, nor do I make it mine. DEUTSCH : F?r alle Seiten, die auf dieser Website verlinkt sind, m?chte ich betonen, dass ich keinerlei Einfluss auf deren Gestaltung und Inhalte habe. Deshalb distanziere ich mich ausdr?cklich von allen Inhalten aller gelinkten Seiten und mache mir ihren Inhalt nicht zu eigen. This Blog's Status is 
Blog Dewey Decimal Classification : 153FWIW, 153 is a triangular number, meaning that you can arrange 153 items into an equilateral triangle (with 17 items on a side). It is also one of the six known truncated triangular numbers, because 1 and 15 are triangular numbers as well. It is a hexagonal number, meaning that you can distribute 153 points evenly at the corners and along the sides of a hexagon. It is the smallest 3-narcissistic number. This means it?s the sum of the cubes of its digits. It is the sum of the first five positive factorials. Yup, this is a 153-type blog. QED ;-) Books I've written
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