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Eunoia, who is a grumpy, overeducated, facetious, multilingual ex-pat Scot, blatantly opinionated, old (1944-vintage), amateur cryptologist, computer consultant, atheist, flying instructor, bulldog-lover, Beetle-driver, textbook-writer, long-distance biker, geocacher and blogger 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 Faith does not give answers, it only prevents you doing any goddamn questioning. You are as atheist as he is. When you understand why you don't believe in all the other gods, you will know why he does not believe in yours :-) Oh, and he also has a neat English Bulldog called 'Kosmo'.

Some of my bikes

My Crypto Pages

My Maths Pages

Thursday, May 17, 2018

Dambusters' Day

75 years ago today, around 1 a.m., the 617 squadron of Lancaster bombers, under command of Guy Gibson, attacked the Möhne dam, the Sorpe dam and the Eder dam at night, intending to deprive the Ruhr valley munitions industry of both water and electricity supplies. The Möhne and Edersee Dams were breached, causing catastrophic flooding of the Ruhr valley and of villages in the Eder valley; the Sorpe Dam sustained only minor damage. Two hydroelectric power stations were destroyed and several more damaged, but Operation Chastise wasn't the complete success it was made out to be by Brit propaganda at the time and the post-WW2 movie.

As it happens, I now live in this area, just 60 kms east of the Möhne dam and 80 kms west of the Eder dam, hence my interest in today's anniversary.

The dams were protected by 2 lines of torpedo nets, so an aircraft could not just drop a torpedo into the lake to attack the dam. However, eccentric Brit boffin Barnes Wallis had developed a 4 ton bouncing bomb which was designed to skip OVER the torpedo nets. It was a pretty big cylinder, see photo below.

The bouncing bomb was mounted below the bomb bay of a Lancaster bomber - which had terrible aerodynamics anyway - on a rig which would spin it up to 500rpm so that it had sufficient back-spin to bounce across the surface of the water, see photo below.

Of the 19 bombers used, 5 didn't make it there. They were flying very low (under 100 feet) to avoid discovery; the actual attack had to be at sixty feet so the bombs would skip properly. Altitude assessment was by coincident fuselage-tip light-beams reflecting from the lake surface. Bomb-release was from 440 yards out, judged by a handheld Y-shaped wooden frame held to coincide with the dam's towers. The back-spinning bomb then bounced over the water, hopping over the torpedo nets (see sketch below), hit the dam and sank down along the wall whereupon a depth fuse triggered it at the designated depth (see sketch). Back-spin kept the bomb up against the dam wall.

Five of the bombs worked as designed and finally the dam was breached (see photo below). About 1600 civilians and POWs were drowned. Since 1977, Article 56 of the Geneva Conventions outlaws such attacks on dams to cause civilian loss of life.

Three bombs sufficed to breach the Eder dam. The Sorpe dam only had minor damage, and neither the Bever nor Lister dams were hit so the Ruhr valley was not deprived of electricity. Only eleven of the bombers returned.

There is a memorial in Nieheim to the 1600 drowned, about 4 miles from the Möhne dam.

Nowadays of course all the lakes are recreational areas where we go sailing upon, swimming in, geocaching at, or motorcycling around. The repaired Möhnesee dam shown in this aerial shot (with 617 squadron's short run-in approach path) is now 105 years old.

Monday, May 14, 2018

Jewish Birthdays

Seventy years ago today, the state of Israel was founded. David Ben-Gurion read their declaration of independence. So doubtless there will be many celebrations, particularly in Tel Aviv, Israel's party-center :-) Tel Aviv has great beaches and 1748 bars, cafes and restaurants - one per 231 inhabitants and its own Iron Dome. All that's missing is a US embassy, which Trump is moving to Jerusalem where the hospitals treat other nutters for "Jerusalem Syndrome" (people who believe they are people from the bible, such as Jesus or Moses etc).

So this blogpost is for my two outed jewish blogreaders, David (NY) and his namesake David (Tel Aviv). Have fun today!

The second birthday commemorated here is the 100th birthday of Richard Feynman, 1965 Nobel laureate, also of jewish descent, born May 11th, 1918 ; one of the ten greatest physicists of all time. I learned a lot of physics from his 3-volume textbook, The Feynman Lectures on Physics :-)

Comments (1)
David (Tel Aviv) wrote "We were celebrating yesterday already, because Netta Bar Zilai won the ESC - European Song Contest - for Israel :-)" I didn't think she was best. First off: since when is Israel in Europe? Many think it was a political fix, otherwise how come Germany didn't come last as usual ;-)

Friday, May 11, 2018

Facial Asymmetry

SWMBO has recently been investigating the phenomenon of facial asymmetry. She does this by taking a photo (shown here in the centre of this tryptich), then placing a virtual mirror vertically along the noseline. That way she has a "right" side which is a mirror image of the left side. And vice versa for the other side. So you can see what the subject would look like if their face were symmetrical.

So this photo above shows what I would look like if I were left-side symmetrical / unaltered photo / right-side symmetrical.

And this photo above shows what our dog would look like if he were left-side symmetrical / unaltered photo / right-side symmetrical.

Weird, huh?

Comments (1)
Liz wrote "That is amazing. Your left-sym dog would look so fierce. And you look completely different in each one." Yeah, it is kind of freaky!

Tuesday, May 8, 2018

Celle Old Town

When we drove through the town of Celle, we decided to take half an hour to photograph some of the old houses in the old town centre (13th-17th century). There were also some scurrilous statues.

The Celle airbase has a statue remembering the Berlin airlift. It is the start of a symbolic bridge. The other end is at Tempelhof airfield in Berlin.

Sunday, May 6, 2018

The 26 dimensional hypersphere surprise!

Having given Star Wars Day a miss for the commercialised nerdy mind-numbing crap it has become, let me blow your collective minds in a completely different way :-)

Draw a square box , four units to each side. Place four unit-radius circles inside it so they just touch one another. These are the black rings in my lousy sketch below. Now ask yourself : what is the size of the largest (red, below) circle you can draw which just touches those black rings?

Applying Pythagoras theorem to the semi-diagonal (green) line we see it is twice root-two units long. Subtracting the diameter (=2) of the unit radius circle, we can calculate the diameter of the central red circle as being root-two minus one = 0.4142...

Circles are spheres in two dimensions. Now let us consider the three dimensional case(sic!) by imagining four tennis balls in a box of side 4 units. Using Pythagoras twice - there are now 3 dimensions X,Y, and Z - we can calculate the diameter of the central red sphere as being root-THREE minus one = 0.732...

Now let us imagine the 4 dimensional box containing 8 unit-radius 4D-hyperspheres. What is the size of the largest (red) hypersphere you can draw which just touches the 8 unit-radius hyperspheres? Using Pythagoras again - there are now 4 dimensions - so we use it over 4 different directions, we can calculate the diameter of the central red hypersphere as being root-four minus one = 1.000

Generalising, for the case of N dimensions, the central (red) N dimensional hypersphere will have a diameter of root(N)-1 as we use Pythagoras theorem N-1 times each along a different dimension.

Indeed for the case of the 26 dimensional hypersphere, the radius will be root-26 minus 1 = 4.099...

So a central (red) 26 dimensional hypersphere will be BIGGER than the box which contains it!!! Does that blow your mind, or what???

Thursday, May 3, 2018

Pied Piper snapshots

Last week our driving route took us through the town of Hameln, the town where the Pied Piper story originated in 1284 AD, so I took the opportunity to take a couple of photos to show y'all.

This first photo shows the metal sculpture outside the (modern) town hall. It depicts the Pied Piper leading the children through the city wall and (permanently) out of town.

The street outside the town museum is paved with cobblestones; some however are little brass plates depicting the rats from the 1284 story.
The photo on the right shows a mannequin of the Pied Piper standing in the entrance to the museum, which is now in the old Leist house, built in 1585-1589 by Cord Tönnis for Gerd Leist.

We had a coffee in the old hall, now a cafe´, then drove on before the rain got us wet, so no photos from inside the museum.

Comments (1)
Liz asks "So does the Pied Piper have any historical basis?" Indeed it does, the story dates from the rats plague of 1284 in Hameln. See wikipedia here.

Recent Writings
Dambusters' Day
Jewish Birthdays
Facial Asymmetry
Celle Old Town
The 26 D hypersphere
Pied Piper snapshots
Gauss @ 241
Find the page :-)
Making up ;-)
Friday 13th
Bomb's away! :-)
Evacuation needed
Manifestations of god(s)
Mondrianesque Bulldog
Norwegian Bliss
Stone Age Megaliths
Bad Signs... ;-)
RIP Ralf Waldmann
Peak Flu ?
Indoor MC Trial
Where's Waldo?
Timetravellers' vocab.

Ain Bulldog Blog
All hat no cattle
Balloon Juice
Cop Car
Earth-Bound Misfit
Fail Blog
Finding life hard?
Greg Laden
Mostly Cajun
Not Always Right
Observing Hermann
On her Bike
Rants from t'Rookery
Reading in Reykjavík
Starts with a Bang
Yellowdog Grannie

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This Blog's Status is
Blog Dewey Decimal Classification : 153
FWIW, 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 ;-)
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