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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 bitch 'Frieda'.

And her big son 'Kosmo'.

Some of my bikes

My Crypto Pages

My Maths Pages

Friday, April 29, 2016

## TBBT model atom is wrong :-(

Each episode of The Big Bang Theory (TBBT) is introduced musically accompanied by a picture, ostensibly of atoms. Normally, TBBT makes a special effort to get the science correct. So I've been disturbed subconciously by the introductory pictures (see their sketch on the left below) and now realise why. It is just plain WRONG!

The picture suggests 3 electrons orbiting a nucleus, each electron having a defined position. WRONG. Neither do we know where the electrons are (cf. Heisenberg), nor do they have such clearly defined orbits, let alone elliptical orbits! They have probability distributions for their positions.

If we are are going to draw such a diagram, the lines represent constant energy levels and hence the rings should be circular. Furthermore, all 3 can't be the same size. Only 2 electrons fit into the lowest ring (ground energy state), the third (the valence electron) will be at a higher energy level. So 2 rings should be shown, the inner having 2 electrons, the outer just one and it should be MUCH further out.

Furthermore the nucleus is shown as being elliptical too. Now since this is a lithium atom (3 electrons), the nucleus can have 7 radioisotopes, two of which (6Li and 7Li) are stable, 7Li being the one from the Big Bang. None of them have elliptical probability distributions. However, 11Li, which has a half-life of 8.6 ms, contains a core of 3 protons and 6 neutrons, and a halo of two independent and loosely bound neutrons. So they could have drawn that halo instead of a misleadingly elliptical nucleus.

Let's just turn a blind eye to the scale of the nucleus and the "orbits" , OK ;-)

This doesn't make the program less enjoyable; I just wanted to explain why the intro irritated the hell out of me until I realised what was wrong with it :-)

Cop Car (USA) wrote " Awwww, com'on, Stu. They are using pictograms, not photographs. Just as street sign pictograms bear no resemblance to real people or things, just as electronic diagrams bear no resemblance to the actual electronics, the pictogram that has been used to indicate an atom has never (and, truly, could not) resemble a real atom. P.S. That same pictogram is the one I used on my QSL cards back in 1955 when I was ostensibly studying to be a (then-termed) nuclear physicist." You know it's a pictogram, I know it's a pictogram, because we both know a smattering of nuclear physics. But I'm not sure that the average non-scientist in the street (think Otis Kline) realises that and may take the 'picture' verbatim :-( This post was just to help set them straight. And BTW, there's no reason why a pictogram cannot represent reality properly (or at least, a better approximation).

Wednesday, April 27, 2016

## First Bifocals :-)

For the first five decades of my life I didn't need glasses. For the next two I've needed distance glasses which also correct my astigmatism and (later) also reading glasses with a closer focus. The latter because the muscles in my old eyes could no longer refocus on shorter distances easily. This has been a bother when out motorcycling : when I stop to read a map or reprogram the satnav or use my phone, I needed to change from my distance glasses to my reading glasses, i.e. also removing gloves etc :-(

So try progressive lenses you suggest? No, progressive lenses are not so great for motorcyclists. Your head gets buffeted by the wind and so the part of the lens through which you look changes too as your head shakes, so things are often out of focus :-(

But I have a good friend Ina who is an optician. After listening to my problem description she made me this pair of bifocals. Special, because she ground the lenses with the line of separation a couple of millimetres lower than usual; it is usually aligned on the lower lid. But as it is, is better for me. Good field of view for normal riding and a small field of view for looking at the map, satnav, phone etc. So now I no longer need to change my glasses at navigation stops. The new bifocals fulfill their design specs (groan!) exactly how I wanted them.

There are a couple of downsides to bifocals in everyday use however. Going down stairs is unfocussed unless I really lower my head a lot. When walking the dogs, it is disturbing when they run through the line of separation. Also the field of view of the reading part of the lens is small, so I use my regular reading glasses still when using the computer because the screen subtends a larger angle than the bifocals' reading lens' parts.

But on the whole, I'm pleased. The ideal riding glasses. Thanks, Ina!

PS: Jokes about me now being able to see the speedo while riding, so no excuses any more, will be ignored ;-)

John Gall wrote "Having had bifocals for a bunch of years, I thought I'd mention an issue I've had. As you mentioned, the field of view is small. However, there are some prescriptions that allow the reading portion of the lens to be across the entire width of the lens - and not just the small acorn-shape of the majority. My vision degraded to the point that the full width bifocal was no longer available (lens became too thick is what I was told). You might ask your friend the optician if you're interested. Good luck with the new specs." Thanks John. Nice to hear from you again :-)
Cop Car (USA) wrote " I am so sorry that you don't live near me so that you could have availed yourself of the services provided by the optical shop that I've frequented since 1959. "Special, because she ground the lenses with the line of separation a couple of millimetres lower than usual." My optical shop people have provided that tailoring for years - since I first went to the graduated focus lenses in my early 50s. Otherwise, I got/get a crick in my neck from holding my head down to peer through the top part of the prescription when driving. I really like graduated lenses, but, understand how they aren't a cure-all. I own three sets of computer glasses, one set of reading glasses, and three sets of driving glass (of which, two are graduated.) I don't know how to throw away old frames. (I was prescribed my first pair of bifocals in early 1958! When we moved to Wichita a year later, my new eye doctor harrumphed that it was ridiculous to have bifocals at that age. I quit tripping on curbs when I stopped wearing bifocals.)" I carry the old distance glasses as a spare when riding, driving and flying (where it is required by law). Wichita? Then the Koch brothers live near you. Anything trickling down there yet? ;-)
Cop Car (USA) replied " Back in the days when I was active as a pilot, I was among the first in the USA to be granted a medical allowing me to wear contact lenses (with the proviso that I carry a spare set of eye glasses!) I had better peripheral vision with the contacts and much better depth perception (which made no sense to me but was the case). Peripheral vision is no longer an issue - I have none! I assume that my wearing "Coke bottle lenses" for glasses brought the Koch brothers to mind? One of the brothers has been reported as allowing that Ms Clinton might be preferred over Mr Trump. That's as political as I plan to get online!" Okay :-)
Hattie (Hawaii) wrote " Trifocals do OK for me. I've been very nearsighted since age 10 and still just take my glasses off to read. The middle distance can be tricky, and I always have to watch my step." OK :-)
Ed (USA) wrote "I don't need glasses, but I have an orange-tinted wrap-around pair of sunglasses for use on the Harley." Dust and insect protection, I assume.

Monday, April 25, 2016

## VERBOTEN !

North Carolina - a sexually fixated state in the USA - has deemed it necessary to regulate which toilets/bathrooms/rest-rooms their transgender people may use :-( I don't know how many transgender scandals caused this, but it's probably a smaller number than the Catholic priest abuses of children or even the number of scandals about Republican politicians soliciting gayly in various mens' rooms etc :-(

Here in Germany we have a different problem. Thanks to Angela Merkel's overly open asylum policy for refugees, we have an excessive (several million) number of refugees and asylum seekers. Some are genuine refugees from war-zones such as Syria who get protection under the Geneva convention. Some are economic refugees from e.g. Irak, others are opportunists from Tunisia, Libya etc who shouldn't have been let in in the first place.

Whatever. But it turns out that we have to educate them about what is and is NOT - mostly is NOT - acceptable behaviour in a public toilet/rest-room, to cure them of their filthy habits. And so official pictogram stickers like the one shown on the right here are now on display in public rest-rooms throughout the country :-(

How primitive do you have to be to need to be told :-

1. Do NOT peek through the keyholes of the ladies' toilets
2. Sit on the toilet, do NOT squat above it
3. NO gay anal sex in the rest-rooms
4. Do NOT urinate against the walls.
Mohammed wept!

Hattie (Hawaii) admonished "I'm sure they can be educated. We're all immigrunts. " Sure, I'm an immigrant here too; but I came with a basic knowledge of hygiene etc. A double-digit percentage of the refugees here cannot read or write, not even in Arabic. Talk about The Left Hand of Darkness! (Nod to Ursula LeGuin there :-).
John (UK) jokes "I can't tell from the pictogram whether the gay is farting or has wifi access at his rear ;-)" Methinks the arcs there are supposed to represent osculation oscillation ;-)
Ed (USA) "College boys here are not much better, see http://cheezburger.com/3328598016 :-(" Okay.
Jenny (Ibiza) laughed "Then there's this". Heh heh :-)
Petra (A) wrote "Thankyou for teaching me a new word : osculate. Now explain the Le Guin nod." OK. One the one hand I was making a snide remark about how desert people use their left hand to wipe their arses (no, they didn't have toilet paper either), using their right hand only for eating (no cutlery, so fingers in dishes). On the other hand I was referring to Le Guin's famous SF novel which teaches us about having to adapt to other, strange, cultures. Go read it, it IS good! Both interpretations are valid :-)
John (UK) "Even if there are 'rules', there will always still be arrogant people who ignore them!" Indeed. Take Donald Trump (please!) as an example. The annual check on his private jet had run out, but he used it for flying to campaign talks anyway. Now the FAA has grounded it, but he can still expect a 277,500 dollar fine and up to 3 years in jail :-)
Jenny (Ibiza) asked "I know that this is the symbol for hermaphrodite, , but what is the symbol for transgender then?" I don't know. Anyone know?
Brian (UK) answers Jenny "See here."
Cop Car wrote "I like the genderless symbol to which Brian led us!" Sort of rounds things off, doesn't it ;-)

Saturday, April 23, 2016

## In memory of The Bard

400years ago today is supposed to be the day William Shakespeare died (and Cervantes, FWIW).

In his memory, take out your King James' bible. Turn to Psalm 46. The 46th word from the beginning of Psalm 46 is "shake" and the 46th word from the end (omitting the liturgical mark "Selah") is "spear". Shakespeare was in King James' service during the preparation of the King James Bible, and was generally considered to be 46 years old in 1611 when the translation was completed.

Just a happy coincidence?

Biker Schorsch crows triumphantly "...And Vale is on Pole! :-)" For you non-bikers : MotoGP rider Valentino Rossi is on pole for sunday's race. Rossi's race number is 46 :-)

Friday, April 22, 2016

## Chimera via Gene Splicing

Recent advances in gene splicing technology and a breakthrough guidance App enable even amateurs like me to construct simple plant-based chimera. In particular, a 2015 breakthough allows scientists (and wannabees) to "breed" plants with characteristic features of animals by splicing their DNA into that of the plant. Politicians will now have to scramble to regulate animal/animal chimera production before someone splices a Trump/Cruz/Frankenstein monster together :-(

In my particular case I wanted to "breed" pansies with panda faces on them because I'm sure they'd sell like hot cakes :-) But I didn't have any panda DNA available, so I had to use the DNA from our bulldogs instead. The face is not quite as detailed as I had hoped, but I'm making progress, as you can see in the photo of a dog/pansy below.

I had originally scheduled this blogpost for the beginning of this month, but then realised that readers might take it for a belated April Fools' joke :-(

Which it is :-)

Jenny (Ibiza) asks "What a vibrant colour! Is the piccy photoshopped?" No, that's the original photo; colour comes probably from growing in the Purple Rain by the artist formerly known as Alive ;-)
Cop Car (USA) wrote " 1) Once again I thought you had lost your mind when I started reading "Chimera via Gene Splicing". Fortunately, this time, I did read through to the end. 2) I had missed seeing your posting about Potwin KS. What a hoot! 3) I thought you might wish to learn about horse gyroscopes: http://www.improbable.com/2016/04/22/introducing-the-horse-gyro-new-patent/#respond. " Coming up at the next rodeo : equine Lomcevaks!

Wednesday, April 20, 2016

## Filthy Food? :-(

I have just been reading the 2015 annual report by our state's food hygiene inspectors :-(

400 state food hygiene inspectors took 85,577 samples. A whole 10.8% of the samples did not meet legal requirements! Mostly this would be failure to declare ingredients which could e.g. be lethal to those with nut allergies. 30% of the milk samples taken were microbiologically unclean, 6% of the sausages. But a whopping 44% of the concentrates were inadequately labelled (undeclared ingredients) as were 42% of the baby-food samples taken :-(

54,000 restaurants, pubs, snack-bars, canteens and catering firms were checked for hygiene. 22.3% were non-compliant with foodstuff laws and ¾ of those had hygiene infringements. How filthy is the food we get served? :-(

In pilot projects in Duisberg and Bielefeld, restaurants were assigned a traffic-light style rating as a result of being inspected. 60-80% improved their ratings from 2014 as a result. There is now a proposal to REQUIRE food establishments to display their traffic-light rating next to the main entrance, but 70 such establishments in the Bielefeld area have put in legal objections to this (guess what colour their traffic lights were!). Apart from these 70, you can inspect the others' ratings via a smart-phone App prior to any proposed visit. It is also proposed to require 120 hours of hygiene training for jobs in the gastronomic industry. I think this is a good idea in view of this report :-)

Junk food everywhere, it seems :-(

Jenny (Ibiza) asks "Can't the inspectors just shut down the really unhygienic ones?" Yes. In Frankfurt (in the state of Hessen) 13 were shut down, 2 of those ON-THE-SPOT!! :-) I don't have the numbers for our state though. In our nearby city, 2 were shut down in 2015 afaik, 1 for hygiene reasons and the other for unpaid taxes (the Al Capone method).
John (UK) asks "Do you have a link to good food hygiene rules?" Yes indeed. Here's the UK Gov food hygiene site. Also I expect that Cop Car has some FEMA or disaster recovery resources about food hygiene. CC?
Ed (USA) asks "Where have you personally encountered bad hygiene?" 1) Mouldy jam for breakfast in a UK B&B, 2) bad sushi (Germany), 3) mould in a shower (US motel), 4) indescribable toilet (Slowakia), 5) mouse turds in the rice in a chinese restaurant (Spain), 6) the Ganges (India) with people still swimming in it . . . I could go on, but you (and I) don't really want to know:-(
Cop Car (USA) wrote " What's wrong with moldy/mouldy jam? You scrape off the mold/mould and eat the jam. Back in the days when we used to seal jars of jam with paraffin, there was very nearly always a ring of mold/mould encircling the paraffin. We thought nothing of it." And I was taught as a child to never eat anything mouldy (but I do eat gorgonzola).

Monday, April 18, 2016

## Potwin, Kansas :-(

Potwin, Kansas, is a small (about 7 blocks square) town, just north of the Interstate 96 and about 40 miles NE of where our favourite Derby blogger Cop Car lives. Potwin's main claim to fame is that it is at 38° N, 97° W. These are the coordinates which sloppy location service provider "Max Mind" thinks is the centre of the contiguous United States (instead of 39° 50' N, 98° 35' W which is where most everyone thinks it should be, just 680 metres from the cross roads labelled as the centre).

Why do I think "Max Mind" is doing sloppy work? They provide a service to convert IP addresses into real world addresses. This involves a lot of guessing! Sometimes they'll just return the address of the centre of the town where the IP address is allegedly located (but perhaps still charge the full fee?). Sometimes they just return the address of the centre of the state where the IP address is allegedly located (but perhaps still charge the full fee?). And sometimes they just return the address of what they think is the centre of the USA (but perhaps still charge the full fee?) :-( How sloppy is that?

And this last "US centre" address is the farm of 82 year old Joyce Taylor, who by now is pretty tired of getting all those traffic tickets, summonses, FBI-searches etc. etc. all thanks to the sloppy database of "Max Mind". Max(imum) Mindless might be a better name :-(

This crap has gone so far that the local sheriff (Kelly Herzett) has put up a sign there demanding (unfriendly?) visitors contact him first before proceeding since he knows full well that the dear old lady is innocent. Pressure on "Max Mind" has now made them change their "USA centre" coordinates to the middle of a nearby lake, so that hopefully any unfriendly visitors will end up there. That is at best a makeshift fix; why can't sloppy old "Max Mind" just return an error message if they can't deduce a real-world address from the IP-address? But then maybe they'd have to return the search fee? :-( At least that'd be honest. If I were Joyce Taylor, I'd sue 'em!

Ed (USA) jokes "It may be only a small town, but they'll get a lot of out-of-town participents if they ever hold a town lottery ;-)" I'll bet ;-)

Saturday, April 16, 2016

## Starshot as a Death Ray :-(

On tuesday I told you about the Starshot project aiming to get to Alpha Centauri via laser-powered lightsails. Now I got to thinking about that 100 GW Earth-based laser array kilometers across. What a danger to aviation and orbiting vehicles that laser beam would be!

Let's assume the laser array is a mile square. That's 5 seconds across at the speed of sound, so it would take an average airliner 7 or 8 seconds to cross. Being exposed to a 100 GigaWatt beam for 8 seconds might very well melt the aircraft or at least cook the occupants :-( The lasers could be on from the moment Centauri rises until it sets, sweeping an arc across the sky over this time period, so the danger path is well known and to be avoided!

But the best defense for an aircraft would be to keep the laser array below its horizon and so out of direct sight. Aircraft fly at up to 40,000 feet so their horizons are about 245 NM away (~450 km). So we are talking about a no-fly zone (=Prohibited Area) some 900 km across, the biggest ever in a non-war zone. That wouldn't help any orbiting vehicles however, so schedules would have to be developed to switch the laser array off when any spacecraft, satellite etc would be crossing the beam's path because the beam is still highly collimated and still powerful for a ways out there into space.

Of course, any birds flying into the beam are going to end up fried. Dust motes and moisture will scatter the beam which will heat the air along its path, giving rise (sic!) to strong thermals and air turbulence refracting the beam. The thermals will cause strong ground winds rushing in towards the beam array to replace the rising air, effectively sucking dust, sand etc into the beam. Laser light scattered by these particles would still be blindingly bright so the laser array could only be approached, even on the ground, when Centauri is below the horizon and so the beam turned off :-(

Methinks the Starshot team needs to look at these issues as well!

John (UK) opines "A laser beam so powerful might never make it out of the atmosphere, but might create a spectacular column of incandescent plasma in the attempt. I don't know enough physics to calculate this." Neither do I, but I guess the Starshot team did the maths already(?). I assume they would place the laser array on e.g. the Atacama desert, 14,000 feet altitude and very low humidity, so most of the atmosphere would be below it. This may mean that my calculation of the diameter of the prohibited airspace is an underestimate, it may be bigger, adding 400 kms (2* distance to a sealevel horizon from 14,000 feet) makes 1300 kms across :-(
Hattie (Hawaii) asks " Have you heard any suggetions that they might put that thing on the top of Mauna Kea?" No, but it's unlikely. Local opposition and it would spoil the seeing for all the telescopes already there.
Doug (Canada) wrote "By the time they get around to trying this the Chinese will have science colonies on the moon - something they are actively working towards at present. Why not build this on the moon where solar power is virtually unlimited and that puts it entirely out of harm's way?" I just did the maths, Doug. Extraterrestrial solar radiation is 1367 watts per square meter at 1 AU. Solar panel conversion efficiency is about 15-20%. So let's assume 200W/m2. We want 1011W for the laser array. So you are looking at a square solar panel array of 22.36 kms on the side. How unrealistic is it to build that on the moon?
Doug (Canada) replied "OK so instead of building on the moon's surface build it in space - the types of panels used in space (multi-junction) are different from those used on Earth - the multijunction cells have between 35 and 40% efficiency." Even so, the solar panels would have to be about 16 kms each side. And then there's the "slight" problem of reaction on the laser array as it fires, how would you keep that thing stable in space? It's only stable on the ground because it's got the whole planet/moon to push back on.
Avi Loeb wrote "Thank you for your interest in the Breakthrough Starshot Initiative. Right now the best way to get involved is to post input on the appropriate topic on our web site. Within a few months we will have a more comprehensive announcement soliciting participation." Thankyou, Avi.

Thursday, April 14, 2016

## Starshot (boldly go!!) :-)

Irish playwright Oscar Wilde once wrote "We are all [standing] in the gutter, but some of us are looking at the stars." [Lady Windermere's Fan (Lord Darlington, Act III)]

In this spirit Russian investor and science philanthropist Yuri Milner announced the ambitious project Starshot on tuesday with the moral support of Stephen Hawking. The program will be led by Pete Worden, the former director of NASA AMES Research Center, and advised by a committee of world-class scientists and engineers. The board will consist of Stephen Hawking, Yuri Milner, and Mark Zuckerberg. Ann Druyan, Freeman Dyson, Mae Jemison, Avi Loeb and Pete Worden also participated in the announcement.

Thousands of lightsailing nanocraft powered by 100 GW phased-array Earth-based lasers kilometers across will be accelerated up to 20% lightspeed, so taking only 20+ years to reach the triple star Alpha Centauri system. From there they should take photos and make other measurements and send the results back via laser beams to Earth (travel time 4+ years). With the spacecraft travelling at 0.2c it wouldn't surprise me if the photos of any planets in the Alpha Centauri system are a little blurred, after all the spaceships are only slowed (if at all) by the Alpha Centauri system's sunlight. Why thousands of these nanocraft? Well, some of them are probably going to hit interstellar dust or Centauran asteroid belts on the way :-(

While we're at it, we should send some of Hawking's DNA along for the ride, perhaps seeding another star system with intelligence :-)

Milner is financing R&D to the tune of 100 million \$, actually building anything on this scale will cost upwards of 5 billion \$, if and when the technology is developed. A valiant philanthropist, but neither he nor I will live to see any replies. But so inspiring to boldly go!!!

Avi Loeb replied to the DNA-transport idea " Good idea ... Indeed, using Nano-crafts is a possible approach to panspermia." Are we Moties perhaps?
Jenny (Ibiza) asks "What are Moties?" I was making a sly reference to the 1974 SF novel by Larry Niven and Jerry Pournelle The Mote in God's Eye about an alien arriving by light-sail. Well worth reading :-)

Tuesday, April 12, 2016

## Autonomous vehicle heuristics?

After reading a couple of diatribes about what self-driving Californian cars can and cannot do, I took a drive through the neighbouring village on a peaceful sunday (little traffic, few pedestrians) to see what potential problems there might be for autonomous vehicles (=AV) and if there were any heuristics I could supply which might help them.

The first photo (above) show the entrance from the north of the village, coming along a country road. Said road has no sidewalks, the asphalt road has ragged edges with no white lines, just grass on the verges. The autonomous vehicle would have to cope with such typical country roads here in Germany. The first sign, a yellow rectangle, defines where the village starts. This implies a speed limit of 50km/h (~30mph). It also implies a change of the authority responsible for road maintenance so generally there will be a change of surface quality (slippery when wet?). The second (triangular) sign warns there may be children running across the road; actually the maps available to the AV may show the kindergarten nearby??? The next triangular sign warns that the road is articifially narrowed (i.e. where the aforementioned children should cross the road). Notice the lane on the right has a lowered sidewalk implying vehicular traffic possible, and , since there were no signs to the contrary, right-before-left may have priority? Still no white line along the edge of the road, just a sidewalk. Subtle too, notice the 30km/h sign (photo top left) which implies a residential lane joining behind the hedge from the right. No priority sign, so right-before-left again?

Just after the road widens again, we get this view. The traffic island with the scraggly tree was put there to stop people from cutting the corners at the junction. The road now has a central white line (do not cross). The lowered kerb again implies there is vehicular access from a hidden lane on the right. The inverted triangle sign warns you to give way at the T-junction. The temporary sign warns of loose gravel, so the road beyond the junction has been recently resurfaced and therefore new road-markings may not have been painted on yet? Loose gravel is dangerous especially for 2-wheelers.

Turning west at the T-junction, after just 3 yards there is the pharmacy with its own row of parking spaces out front. Surely the AV's maps would have this marked? Note that weekdays unwitting drivers may be backing out of these parking slots, just 3 yards from the T-junction! And yes, the road was recently resurfaced (getting rid of the potholes) and no, the white lines haven't been repainted yet! BTW, do the autonomous vehicles steer around potholes and raised or sunken manhole covers? Bikers do, and some cars.

Twenty/thirty yards on a blue P-sign indicates that yes, the village does have a central parking facility, just into the dead-end (also signposted). Because it's a dead end, cars will have to back out if all the parking slots are taken, there is no room to turn around otherwise. The name of the street "Hukstweete" implies it is only wide enough for 2 people walking abreast. Would the AV's computer know this and deduce the no-turning heuristic? I doubt it. Note also the small playground for little kids along the side of the main street! Would the AV's computer recognise this and deduce the potential danger? I doubt that too.

Final photo. The green column on the right is a bus-stop. Rules for overtaking stopped busses differ from country to country in Europe. But since the AV knows where it is, it must know which rules apply. I wonder if the AV knows that there are places in the UK where you do NOT drive on the left (e.g. Savoy Court, in London)? The striped flag is just advertising the village bakery; this implies lots of early morning parking traffic. Again, the sidewalk parking slots mean the deparking traffic backs out into the main road :-( Fifty yards on, the road forks around the church. The diamond-shaped yellow sign (if the AV noticed that?) implies you have right of way over traffic emerging from the right of the church. And now the REALLY subtle heuristic. This was on a sunday. The church is flying flags. This implies the local Catholics (the religious majority here) are celebrating something. When Mass finishes they will pour out, line up in the road 4 or 6 abreast and march e.g. to the war memorial or graveyard or whatever. Blocking the road. Rules for overtaking marching columns, funeral processions etc, vary from state to state in this country. Does the AV know that?

In real time, it takes much less than a minute to drive this distance (it's a small village), so the AV needs to think fast. Note that there were no really difficult situations in this example, like road-works in progress etc.

I would appreciate it if you would mail any other heuristics you may have for an AV. I am also open to discussion about AV state of the art.

Jenny (Ibiza) asks "So why are bits crossed out?" Because I forgot the rule that says 'If you have to cross a sunken kerb, you do not have right of way, even if right-before-left', and only noticed it after publication :-(
Ed (USA) sent a link "The AV has to react to ALL signs, unlike these 11 foot 8 idiots :-(" Hilarious link, thanks Ed!
David (NY,NY) wrote "Here's a good heuristic :-)" Indeed :-)
Hattie (Hawaii) wrote "...And I like your take on driverless cars. Just the endlessly complex situation in a small area should be enough to demonstrate the difficulties. We have these very complex meat machines that handle this sort of situation well. Let's continue to use them instead." Apropos meat machines, go read Terry Bisson's 1990 SF story :-)
John (UK) wrote "Give us three everyday examples you think would be hard for a self-driving car." OK; 1) ferries, 2) feeding the parking meters, and 3) determining when it is dirty and so driving through the car wash.
Schorsch (D) added "4) following verbal and gesticular instructions of police officers ;-)" Oh yes ;-)

Saturday, April 9, 2016

## UK Supersonic Intercepts booming

Yesterday 2 Typhoon Eurofighters went supersonic as they were scrambled to intercept a business jet over Northampton, UK. Photo here. The business jet was on a flight from Cherbourg in France to Dublin in Ireland. A straight line would have it tracking over Cornwall and South Wales (e.g. the house of Welsh blogger Liz in Swansea). But following IFR routes put it over the Northampton area where it lost all radio contact, not replying to controllers' calls. 9/11 style fears quickly arose. So the Rapid Response Fighters were scrambled from RAF Coningsby, just 3 minutes away at Mach 2. They intercepted the jet and forced it down to land at Cardiff airport where its innocence was established by ground security forces.

Normal pilots' procedures in case of a loss of radio contact is to set your transponder to the "Loss of Comms" code, just one click away from the "I'm being hijacked" code (no, I won't tell you the codes), and then follow your clearance to your destination. Maybe in these days of terrorism the RAF is being supercareful?

Back in the 1960s, we would often scramble our EE Lightnings from bases in Scotland to intercept Russian TU95 Bears as they approached UK airspace. The EE Lightning was a great interceptor, faster than the Typhoon and with a better rate of climb and ceiling altitude, but with a shorter range and less armaments. The UK is still intercepting Bears on a regular basis :-(

People on the ground, no longer used to sonic booms as they were in the 60s, twittered in concern, asking what the big bangs were. One even twittered that her whole house shook. If that is the case, I suggest she have a serious talk with the builder who built her house!

We get sonic booms 3 or 4 times a year here. Usually when the fighters practising dogfighting lose track of their speed when pulling out of loops.

Sonic booms are the sound of freedom! Don't complain, you pants-wetters!

Jenny (Ibiza) complains "That's a terrible pun in today's header!" You think so? I thought it was bang on ;-)

Thursday, April 7, 2016

## Iron Annie turns 80 :-)

Lufthansa's beautifully restored Junkers 52/3m Trimotor - built in Dessau in 1936 - turned 80 yesterday. She still flies about 9000 paying passengers each summer; three years ago I had the fortune of being one for a 42 mile hop Ahden to Hamm. Wikipedia has an informative JU52 article.

Klaus (Alaska) sent a link, writing " They look pretty much alike ?" Not quite. The Ford Tin Goose is a highwing, the Junkers a low-wing plane with narrower landing gear. At Oshkosh in 1984 I inspected a tri-motor Stinson(?) ; it is lined with wood on the inside to give an impression of luxury. Here's my photo from 32 years ago, so excuse the quality :-)

Klaus (Alaska) replied "Sorry that I missed the big difference, high wing, low wing, looks like I'm getting old." That's still better than the alternative ;-)

Tuesday, April 5, 2016

## Vikings in America

Archeologist Sarah Parcak and her small team recently found evidence of another Viking settlement on the very western tip of Newfoundland (=Vinland). Details here.

Before 800 AD the Viking culture had spread north up the coast of Norway and SE into the Baltic and around Sweden. They had discovered Britain, Ireland, the French coast down as far as Brest. Around 800 AD they reached the Shetland Islands, in 860 the Faroes and 870 they reached and settled in Iceland. In 985 Eric the Red landed at Brattahlid on the southern fjordland coast of Greenland. Bjarni Herjolfsson sailed north up the coast of Labrador in 985/6 and then turned east again, landing in Greenland somewhat south of Eric's site. Leif Eriksson sailed up the western coast of Greenland in 1000 AD, turned west to Baffin Island (one settlement there) then followed the eastern coast of Labrador south until reaching Newfoundland. Evidence of a Viking settlement in L'Anse aux Meadows (on the northern shores of Newfoundland) was found there in 1960. Thorfin Karlsefni followed his route in 1005 AD, also reaching the northern Newfoundland settlement. So far, so good :-)

Now Sarah Parcak has taken an innovative approach. She pores over satellite photos looking for evidence of what had been buildings now under the surface of the ground. While this works well for stone buildings, remember the Vikings didn't use stone, but wood :-( Nevertheless she found evidence of iron-working (a smithy's hearth, afaik) and went there with her team for a dig. Success! They found another Newfoundland Viking settlement on a western headland (see the link I gave above for details).

So, America! You have to give up Columbus day and celebrate Leif Eriksson day (October 9th) instead :-) Anyway, Columbus never set foot in America, he just piddled about in the West Indies. And it was not until 1513 that Juan Ponce de Leon set foot on Florida becoming the first named European known to have done so. And Florida has had many ponces since ;-)

But the Vikings (probably Leif Eriksson and his hardy band of sailors) were the first Europeans to reach America :-) All praise to Odin! Wotan effort :-)

Schorsch (D) notes "There were Vikings on the Isle of Man, there was a settlement at Peel." Not only Peel; I've seen Viking runestone graves in the graveyard at Laxey. BTW: Lax is Norse for Salmon, so laxe (by the salmon) means river and laxey means by the river. If I remember correctly, there is one stone written in younger futhark which reads (my translation) [Here lies] Olaf [who] built the boat [that brought us here].
Ed (USA) asks "So where are they all now?" Much of the Viking's longer travels happened in the Medieval Warm Period (about 950 to 1250 AD) when the crops were plentiful and fishing was good. The last written records of the Norse Greenlanders are from a marriage in 1408. The Little Ice Age was from about 1300 to about 1850. Cold probably ruined the crops as those northern lands glaciated and the seas froze so there was less access to fish. So I suspect they died of starvation in the Little Ice Age. Remember, as late as 1780, New York Harbor froze, allowing people to walk from Manhattan to Staten Island :-)

Friday, April 1, 2016

## TBBT suppresses the F-bomb !

Punctually at the beginning of this month I have become aware that TBBT is deliberately suppressing details of the F-bomb :-(

Several of my regular readers I know are fans of The Big Bang Theory (TBBT), for those who aren't this is what makes it surprising : Theoretical physicist Sheldon Cooper, experimental physicist Leonard Hofstadter (not related, afaik, to the illustrious Douglas R. Hofstadter, author of that brilliant book "Gödel, Escher, Bach"), and astronaut/engineer Howard Wolowitz (foreword contributor to Dave Zobel's explanatory textbook) all have sufficient knowledge of nuclear physics to make their own F-bomb if they wanted to.

Even Penny, who lost her maiden name when she found out what "maiden" meant, could surely make an F-bomb ;-) Not sure about Raj & Amy, though.

I come to the conclusion today that TBBT deliberately avoids the F-bomb or even discussing it at all. I can only assume that this is political correctness gone wild: they are afraid that terrorists might watch the program and learn to make their own F-bomb! Such terrorists might be IS-Islamists attacking the local fried-egg and drinking establishment (a´ la "Egg Bar").

But it is common knowledge how to make an F-bomb. The name is taken from the chemical symbol of the first of its four component parts. The F-bomb is made from equal parts of fluorine (atomic number 9, atomic weight 19), uranium (92, 238), carbon (6, 12) and potassium (19, 39.1). These parts are assembled sequentially in less than a half-second in the sequence given above, usually accompanied by an acoustic shock wave.

In some countries it is difficult to obtain Uranium; Sheldon Cooper is know to have failed in his attempt in the USA. If this is so for you too, just use some lemon meringue pie instead, a useful approximation to yellow cake. Here in Germany we use Iodine (53, 126.9) instead of Uranium. The Irish have a variant using Iron (26, 55.8), Carbon and Potassium. Just as effective!

So if anyone attempts to tell you a tall story today, just lob an F-bomb at them, maybe adding one part of oxygen (8, 16) then two of fluorine. The F-bomb yield is of the order of megatons. No, sorry, that was Mrs.Wolowitz.
Otherwise : Bazinga! :-)

Cop Car repukes (sic!) me " You've really gone off of the deep end, my friend!" only to follow up 1 minute later with "How stupid of me not to have realized that, while I am still in March, you have launched into April!" April Fool! ;-)
Barbara (UK) also thinks "That's rude :-(" No it isn't, I never use the word, I merely reference it. The rest is your prudity :-)
Jenny (Ibiza) complains "It has taken me 2 hours to get the islamic pun. Brilliant!" Thankyou :-)
Dieter (A) opines "With all those buzzwords, I think you are just trolling the NSA's net-content surveillance bots!" Indeed, punctually on April 1st :-)
Schorsch (D) wrote "Microsoft's AI chatbot Tay which got trolled into going full Nazi within 24 hours should have been released on April 1st, not a few days earlier." I agree, it was hilarious while it lasted though. MS forgot to let Tay check allegations via e.g. Wikipedia, so that she could distinguish fact from fiction. A severe case of AI Trumpitis, IMHO :-(
Cop Car wrote "... It wasn't until late last night (my time) that I found that I had failed to scroll down to the last paragraph of your April Fools posting. Had I read that I MIGHT have caught on to why you were leading people down the garden path. Good one!" Dieter was the one who caught the deep April fool troll target ;-)
Ed (USA) wrote "...on april 1st I heard that transgender people can choose their own Jenner-tals ;-)" Groan!

-
Recent Writings
TBBT model atom wrong
First Bifocals :-)
VERBOTEN !
In memory of The Bard
Chimera via Gene Splicing
Filthy Food? :-(
Potwin, Kansas :-(
Starshot as a Death Ray
Starshot :-)
Autonomous vehicles
UK Supersonic Intercepts
Iron Annie turns 80
Vikings in America
TBBT & the F-bomb
North Korean SSM ;-)
Crap Abble :-(
A 4 line proof :-)
Bags of Fun :-)
St.Patrick's day :-)

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