85 ways to tie a tie

My father taught me to tie a tie on my first day in high school. By the end of my first term, tying a tie had lodged itself in that part of my mind sometimes referred to as muscle memory. I don't know how I do it, I just do. It is the same type of memory that helps me touch type or drive a car.

Thomas Fink and Yong Mao, two Cambridge scientists, have shown that there are exactly 85 ways to tie a tie. Using Fink's encyclopaedia of knots I discovered that my father showed me how to tie knot number 31. That is an Li-Co-Ri-Lo-Ci-Ro-Li-Co-T for the mathematically inclined, or a Windsor knot as it is more commonly known.

According to Fink and Mao, the Windsor has some nice properties: (1) It consists of eight moves, not just three or four like some of its cousins; (2) It has three centre moves resulting in a wide knot; (3) It is nearly symmetrical. When the number of right moves are subtracted from the number of left moves, the result is one; (4) It is completely balanced. There is no switching back and forth between clockwise and counter-clockwise windings; (5) Finally, the Windsor's knotted status is negative. When it is loosened, removed over the head and the thin end pulled, it leaves no knot.

Two days to go till Christmas. What are the odds of getting a tie this year?

Only in Holland

Only in Holland do you get shooed out of the building at 4 pm on December 5th. After all, you should be back home celebrating Sinterklaas with your family.

The Clocktower

Last night I attended a party to celebrate the successful PhD defence of a colleague. The party was fun, the location was spectacular. It was held on the second story of a stylish old Philips building: de Klokkentoren (the Clocktower). De Klokkentoren is the 70 meter high eye-catcher of a former industrial complex in a part of Eindhoven called Strijp-S.

On my first trip to Eindhoven I distinctly remember seeing de Klokkentoren toward my left as I entered the "City of Lights" by train. Unfortunately, most of the architectural heritage of Strijp-S has since been or will soon be demolished. One can only hope that this does not prove to be as short-sighted as the systematic destruction of Brussels' Art Nouveau masterpieces during the 1960s. Once it's gone, it's gone.

On a positive note, it seems de Klokkentoren will not meet the same fate as the buildings that used to flank it. Apparently, it has been designated a national monument and will be refurbished for housing and commerce. Now, if only we could save the W-Hal.

Walking on the Moon

When I woke up this morning, an excerpt from an old song by The Police was washing through my head.

Giant steps are what you take
Walking on the moon
I hope my legs don't break
Walking on the moon

Imagine my surprise when I turned on my car radio: today is the 50th anniversary of the launching of Sputnik 1, the first artificial satellite to orbit the earth. This in turn sparked the space race, culminating with Neil Armstrong walking on the moon in 1969. And so - the pun is irresistible - we have come full circle.

Souss Africa, Sirty-seex; Eengland neel!

Concerning last night's rugby in Paris, I cannot say it better than this article on 24.com (from which this post's title was also borrowed):

"The South Africans were coldly focused, clinical in execution and unwaveringly composed as they set about blasting England’s sweet chariot right off the park."

I came to the same conclusion in the crowded Irish pub in Eindhoven where I watched the game. I was surrounded by enthusiastic green-and-gold brandishing Dutchmen. As the final whistle came closer, they loudly assured one another that "we" - "De Springbokken" - were about to win by an even greater margin than the 0-36 already on the scoreboard. What a match!

Room with a view - part 2

This morning I knelt down to tie my shoelace in our kitchen. Here you see photo of the view I had when I looked up. Yes, that is a shark and a squid poking out from our washing machine. (And no, this was not set up.) I could not help snickering: life certainly has changed. For the better.

Dead weight

"That's lovely, but do you really need it, little man?" my grandmother would say as I showed off the latest acquisition I had made with my pocket money. I would always reply "Come on grandma, the war has been over for decades!" (The second world war and the resulting economic slump also had a profound influence on the psyche of the war generation in South Africa.)

Yesterday, I spent some of my "pocket money" on a new wallet - the previous one having worn out. When I got home I took the contents from the old one to sift out those things I do not need or use. I was dumbfounded by how much dead weight I carry in the form of various customer cards. Every day I haul around this useless plastic due to unrealistic financial incentives. After all, my fiftieth loaf of bread is free! I could not think of one time I have profited from this. Away with this, I say!

Of course, dead weight is not only found in our wallets. Our lives and our homes are full of it. And all of this translates to dead trees. I refer here to the earth's finite resources that are being used up for no purpose other than window dressing. I am not suggesting that my new-found refusal to get coaxed into more plastic carrying customer-discount scams will have any significant influence on the environment. However, grandma was much more of a visionary than I realized.

My grandparents lived comfortably but frugally. Nothing was bought without an express purpose and without being absolutely necessary. Their home was not cluttered by dead weight. Before replacing something that had broken, they would first enquire whether it could be repaired. Case in point: long after the advent of autofocus SLR cameras, my grandfather was still shooting with a beautiful old Rolliflex. "There's nothing wrong with it, and besides, the picture quality is far superior."

After all this moralizing I realize that my grandmother would not have bought a new wallet in the first place. She would have had her old one repaired. Shame on me.

Room with a view

Earlier tonight I visited the website of a professor whose undergraduate courses I took a few years back. On it she has a link to the view from her office. Could there be a correlation between the lovely summer's day and the empty parking lot in front of the Department of Computer Science?

From my office I look out over the Eindhoven city centre. In the distance I can just see the beautiful old Philips light bulb factory, De Witte Dame. If I look carefully, between the trees I can also see Le Corbusier's Objet Mathématique, the last remnant of the Philips pavilion at the 1958 World Exposition in Brussels. Not the purple Jacaranda trees of my home town, but not bad either.

I recently visited a friend who used to share my office, and view, in Eindhoven. After graduation he got a position with a first-class research lab. His new office does not have any windows. So much for a room with a view.

Serious about recycling

When it comes to the environment, Belgians are quick to point out that their government enforces recycling by law. Apparently, Belgium is serious about recycling and will slap you with a fine if you are not.

I recycle because I subscribe to the idea of sustainability and not because I fear the Belgians. As I often do, this morning I set out early to our local recycling depot. Unfortunately, I was told that today they cannot accept paper. This is the fourth time this has happened. The following flashed through my mind. Get serious!

Independence day

Today India celebrates sixty years of independence from Britain. My son also set his first small step toward independence. This morning my wife and I took him to daycare for the first time. A great day for freedom? I am not sure. As I left my blue-eyed boy with strangers, I felt rather like a villain.

Travel, but not as we know it

The Back of Your Head

When I was a child, my mother had two mirrors inside opposing doors of her wardrobe. When you opened both doors at an angle of roughly 90° (facing each other), you could see what the back of your head looked like.

Even more intriguing was the Droste effect that resulted from the recursive bouncing back and forth of light between the mirrors. There were infinitely many me's getting progressively smaller! I also remember staring at my mother's tins of Royal baking powder. Each tin had a picture of an identical, but smaller tin on it. And on this tin, there was a picture of another tin. I remember squinting my eyes to see the picture on this third really tiny tin. Although I could not see it, I was convinced it must there.

These were my first encounters with recursion. I would meet it many times more. For instance, on the cover of Pink Floyd's album Ummagumma. (Apart from repeating, the band members also switch positions in every nested photo.) Of course, recursion is also found in computer science. Here it refers to the practice of defining a function such that its definition contains a call to the same function.

The past week I kept coming across programming problems for which recursion gives an elegant, easy to implement solution. Every time I do, I cannot help giving a little whoop. My colleagues assure me that this is very uncool. After all, we all have seen recursion many times before. I disagree. Every now and again, I think it is good to delight in opening that wardrobe to see what the back of your head looks like. Even if you have seen it many times before.

Walking the Dog - Part II

Apparently I am way out of touch. In a previous post, I wrote about the revelation I had regarding contemporary dog owners in European cities.

Yesterday, I was again doing my rounds in the neighbourhood park with my baby boy. On my way there a cyclist towing a doggy trailer flashed past. "Oh look, a cyclist towing a doggy trailer... Hold on, a cyclist towing what?!" This was no home-made effort either. No sir, this was a commercially made kennel-on-wheels. I put myself at ease by reasoning that if huskies have been pulling sleighs for hundreds of years, then this dog is just getting some justice for his northern cousins.

No sooner had I forgotten about the trailer encounter than one of those dog-in-a-baby-carriage-ladies appeared. Not being naïve enough to be thrown again by this sort of thing, I didn't winch. Only, it wasn't a baby carriage. Her canine companion was getting a free ride in a pushchair specially made for dogs. As with the trailer, there is a company out there that earns revenue making buggies for dogs. Fascinating. Right?

When I got home, I told my wife about my amazing discoveries. She said she had recently seen an television item about a dog boutique. In the very city we live in! Go figure, doggy couture. Here is a million dollar idea: a dog breed with a Burberry plaid or Yves Saint Laurent chequered coat.

Getting the Work Done

Last Friday my wife needed the car, so I worked from home. With me I had some source code for a research prototype that I had been working on. I got up bright and early, started up my C++ compiler and started "working".

There was just one problem, at home I have a different compiler than the one I use at the office. The source code that compiled without any problem at work now suddenly gave me linking errors. I quickly went through the list of usual suspects (circular inclusions of headers, outdated object files etc). To no avail. A few hours later I was still scratching (banging?) my head and loudly sighing in self-pity. (Of course, at least to some degree, by now it had also become an issue of pride and outsmarting the compiler.)

My wife came in and asked "what's wrong?"
"I'm not getting any work done," I said.
"What do you mean? You've been sitting there since 7 this morning."
I grunted in frustration, "Yeah, but I can't get it to compile and I can't find the problem."
"Well, you're still working."
"But I'm not getting any work done!"
"But honey, searching for and solving problems IS getting the work done."

I finally did solve the problem (with a workaround). But I'm still not convinced that dealing with different compiler idiosyncrasies is "getting the work done". Maybe I am just too impatient (another point my wife never fails to emphasize).

Scones

Last weekend I suddenly had an irresistible urge for scones. Having lost my mother's recipe, I googled "scone recipe". The first result was a link to BBC Food. Once again my favourite broadcasting corporation delivers!

About forty minutes later we were feasting on scones hot from the oven. The only minor issue was that we did not have any cream. As any scone lover would attest, scones are best enjoyed with jam and clotted/whipped cream (and washed down with tea).

The photo at the top left is of yesterday's (double) batch. This time I made sure that there was ample cream.

The Times they are A-Changin'

Well, the times certainly are changing. When he brought out a cover version of A Hard Rain's Gonna Fall, Brian Ferry did the world a terrible injustice by releasing what is in my opinion one of the worst Dylan covers to date. Fortunately, on his most recent album there is one of the best covers of The Times they are A-Changin' I have ever heard. I guess we'll call it quits then.

Skwish

A few weeks ago I bought myself... Wait! Let me start over. A few weeks ago I bought my son an awesome toy: a Skwish. The Skwish is based on the principle of tensegrity - a term first coined by Buckminster Fuller - and was designed by Tom Flemons, founder of Intension Designs.

The term tensegrity is a contraction of "tensional integrity" and refers to structures that get their strength by a clever (and often elegant) combination of tension and compression elements. Man, I can't wait to explain this to my boy when he gets older! This is what I will tell him:

The toy is made from wood and elastic cord. There are six wooden rods grouped into three pairs. The rods in every pair are parallel to each other and every pair is positioned orthogonally to every other pair in 3D. Elastic cord keeps the rods in position (tension). The rods, in turn, keep the cord from collapsing into a shapeless heap (compresion). This results in a structure that is quite agile; you can pull and twist it, but it will always rebound to its original shape.

Every rod is capped on both ends by two ellipses and is threaded trough another that is free to move over its length. This makes a nice sound that my son likes. The colours used for the rods and beads are not incidental either. Quick analysis shows that the designer uses the three primary (red, yellow, blue) and three secondary colours (green, violet, orange). Every pair of parallel rods and their spheres are coated in complimentary colours (pairs of opposite colours on the color wheel; red:green, yellow:violet, blue:orange).

I hope my son has as much fun with his Skwish as I did. As long as he knows that when he grows tired of it (how could he?!) it goes back on my shelf.

30 Cents

At work there are two quick ways for me to get a cup of coffee.

About five meters from my office door there is a coffee vending machine. You put 30 cents into the coin slot and about 15 seconds later it presents you with a cup of the most vile "coffee" I have ever tasted. The term "muddy water" comes to mind.

I can also run up two flights of stairs to the canteen on floor eight. There you take a paper cup, put it under a spout and press the button labelled "Koffie". About 10 seconds later you can take your cup and proceed to the cash register. Once you're there - provided you have correct change - you just plonk your 30 cents on the counter and yell "Doei!" Usually, you're answered with another "DOEI!" from somewhere in the back.

When I opt for the first, I usually regret it. When I opt for the second, I leave sipping my beverage feeling very satisfied. Perhaps because I grew up in a large city where no one ever trusted me to "just leave the money on the counter". (The coffee is not bad either.)

Mentors - Part III

My PhD adviser gave me the following word of advice today:

"You're a father now. That means at home, you're last in line. You're at the bottom of the pecking order. Get used to it."

I guess that is another quality of a mentor - when necessary, they can be brutally honest ;-)

Keith Tyson - Large Field Array

In two days' time Keith Tyson's installation Large Field Array will close at the De Pont museum in Tilburg. Fortunately, I was dragged there today by my PhD adviser.

Was it worth it? Absolutely! This is, without a doubt, one of the most fascinating art exhibits I have ever seen. The work consists of 300 individual pieces of art that occupies the floor and two walls of a rather large hall. The objects are placed 120 cm apart in a large grid and range from ultra-realistic sculptures to extremely detailed scale models. The position of a particular object is not random but as a function of its relation to others. Most of them fit inside a 60 x 60 x 60 cube, but some do not.

Of course, the idea is to coax the viewer into trying to make sense of this incredible complexity and diversity. The artist certainly succeeded: I saw elderly ladies get down on their knees to inspect things from up close. As for us, we did not stop darting between the different objects for three hours, and I suspect we could have stayed at it for weeks.