23 May 2016

Tatoo obsession in Sweden

Swedes have a huge obsession with tatoos:
Tatoos have become so commonplace in Sweden that Stockholm is now believed to be home to the world's most inked population outside of tribal societies. [Source]

I wrote about this in an earlier post because one of the first things I noticed in Sweden was that shops that carry magazines and newspapers have many more publications devoted to tatoos than to news. Sometimes one cannot find newspapers (other than trash tabloids) but there are surely several (sometimes dozens) tatoos magazines always available.  I tested this today at the main airport in Stockholm. I asked, at Pressbyrån, if they have any newspapers. They pointed out Expressen  to me.  I said,  "that's a tabloid,  do you have any regular newspaper?" They pointed out Aftonbladet to me.  I replied that this is also junk press.  "Any serious newspapers?" No.  None.  And yet they had several magazines on tattoo.

It's very hard to find newspapers at the main airport of Stockholm.  As for foreign press,  forget it,  there is none.  But tatoos are everywhere.  There is even a tatoo parlor at the Stockholm airport:
And they're proud about it: it's the first airport in the world to have a tatoo shop. (Caveat: there's nothing decent to eat at Stockholm airport,  but there's a place where you can get a tatoo.) I guess it's important to some to get their tattoo before they fly.

I observed these peculiarities long time ago.  But I didn't know that Sweden has as many tatoos per capita as in tribal societies.

N.B. See my old  posting on 3 Swedish fetishes:

15 February 2016

Maps lie more than one usually thinks

I performed the following experiment with students of mathematics. I showed them a map of Russia on google and took a point very far to the east (Uelen, a village in the Chukotsky District next to the Bering Sea) and a point very far to the west (Venekyulya, a region in the Leningrad Oblast, at the border with Estonia). The distance between Uelen and Venekyulya is, roughly, the largest distance between two points in Russia, which is about 6000 km. I asked the students to draw a path between Uelen and Venekyulya whose length is 6000 km. Some drew the path P1 shown below which is a straight line between Uelen and Venekyulya on the google map. Others, realizing that the map is a projection of a sphere, drew path P2, slightly curved upwards.
When I showed them the actual path (see below), they were all surprised. They thought it was wrong. How can it be that the "straight line path" is so much curved upwards? Well, that's because the distortion of the map increases very rapidly when we move away from the equator.
If I had shown them the actual map, on a sphere, then they would have known what to do: they would have drawn an arc between Uelen and Venekyulya that is part of the unique great circle between them, that is, the circle centered at the Earth's center and containing Uelen and Venekyulya. This arc almost (but not quite) passes from the North Pole. To see this, we need to look at the Earth downwards from the North Pole. The picture then becomes clear and the apparent contradiction is resolved.
(Credits for this image go to https://www.jasondavies.com/maps/rotate/)
The moral of this is that we should never believe what we see. (In fact, we should never believe in anything.) Only when we have further evidence, provided by experiment, measurements, or mathematical proof should we "believe" what we see. But then the verb "believe" becomes irrelevant; at this point, we know, we do not believe. We may believe something, temporarily, until further evidence, or we may believe something because someone else we trust has done the work for us. But we should never believe something because our eyes saw it, or because a teacher once told us, or because the government or administration says so, or because a religious, for example, book writes.

One thing that bothers me with some students (and some teachers) of mathematics is that they may be comfortable with the geometry of a 5-dimensional hyperbolic space because they may have seen it in class, passed an exam on it, or doing research on it, but may be uncomfortable with down-to-Earth [sic] geometry, including knowing 2-3 proofs of the Pythagorean theorem. O tempora o mores!

1 February 2016

Nobel peace prize for Greek islanders

Earlier this year, Vanessa Redgrave praised Greek islanders for helping  refugees arriving en masse in Aegean islands such as Kos. It was suggested that the Nobel peace prize be given to Greek islanders who "since the very beginning of the refugee crisis, fishermen, housewives, pensioners, teachers -- ordinary residents of the Greek islands and other volunteers have opened their homes and hearts to save refugee children, men and women fleeing war and terror."

And now, there is a petition on the internet  about this. A petition launched by a Avaaz is asking for the Nobel Peace Prize to be awarded to these unsung heroes

Greece does not have the means to police its borders. It's in a deep financial crisis, instigated by previous corrupt governments in cooperation with the European Union lenders who turned the blind eye when "checking" obviously fake balance sheets. Nevertheless, at the individual level, and despite the rise of neo-Nazis, many Greek islanders are indeed doing as much as they can--and more--to aid the refugees, at least those who arrive alive.

In the opposite direction, EU gives Greece warning to fix border 'neglect'. Easier said than done, of course. There is no money. Greece is cutting down on police forces because they can't pay them.

The Nobel peace prize would be a good gesture but we should keep in mind that this prize is quite controversial: it has been given to people and organizations supporting violence, to others who have been directly responsible for the deaths of hundreds or thousands, to corrupt people, and has been largely politically motivated, i.e., a Nobel peace prize award is often given as a statement of whom the world should consider as proponent of peace, not the one who actually is. Here are some very controversial Nobel peace prizes:
2012: European Union (really?)
2010: Liu Xiaobo (who, basically, is a voice of American-style democracy, including support of US-initiated wars)
2009: Barack Obama (who me? he said, but he accepted it)
2004: Wangari Maathai (who claims that AIDS was invented by first-world scientist in order to depopulate Africa)
1997:  Jody Williams (for her work in banning anti-personnel landmines but isn't it Dyno-Nobel who makes landmines?)
1994: Yasser Arafat, Shimon Peres, and Yitzhak Rabin (could that be a political statement? duh!)
1989: The Dalai Lama (paid directly by the CIA in the 60s)
1979: Mother Teresa (who let people die as they would go faster to paradise; read Hitchen's "The Missionary Position")
1973: Henry Kissinger (probably, the most ridulous peace prize ever given; again, read Hitchen's "Trial of Henry Kissinger")

To summarize, Greek islanders will welcome the prize even though it's a controversial thing. At the same time, EU should make up its mind: support the islanders get the prize or punish them for not doing enough. At the minimum, they should be helped. Those people in Kos who risk their lives to help half-dead immigrants are not the ones who stole public money and led to the crisis. Those who did are still enjoying their loot.

31 January 2016


A well-designed quote conveys interesting and often powerful ideas and makes one think for a time disproportionately longer than the length of the quote.

I have decided to add a quotes collection on my page. I try to restrict to quotes pertaining to Academia, but I can't promise I won't divert.

Anyway, here is a quote that impressed me today:
  • Most [people] discover that they have often be working in the affine plane without realizing that it could be so designated. (H.S.M. Coxeter)
Coxeter is the Grand Man of classical geometry who lived in the 20th century. Some of his books should be compulsory in middle/high school education. Alas, exactly the opposite is happening: to my total dismay I learned that Swedish schoolchildren never learn why the angle bisectors of a triangle pass through the same point. Instead, I was told, a Stockholm school made computer games a mandatory course. Not designing computer games, mind you, but playing them. No wonder that university students have no clue that there is a proof of the Pythagorean theorem. Yes, they can state it (and so can the greengrocer) but not only do they not know a proof, but--what's worse--they're not even aware that a proof is needed.

Back to the affine plane, however, even under ideal schooling circumstances, what makes the affine plane so elusive is the quick passage from Euclidean geometry to coordinate geometry (thanks Descartes!). Typically (I guess not any more), a schoolchild would learn a lot of Euclidean geometry in school but then pass on quickly to linear algebra in his/her first-year university course. The affine (and so goes for the projective) plane, responsible for a lot of elementary mathematics, would go by very quickly, if at all.

Pondering the Coxeter quote carefully is, perhaps, all is needed in order that the affine plane be re-surfaced from the stack of one's toolset.

30 January 2016

Violence in Sweden

There are a lot of things happening in Sweden that makes everyone who is not Swedish feel very uncomfortable.

The most recent of them is the attack to immigrants by about 100 masked people in central Stockholm. Although it appears that Sweden is welcoming immigrants it is rather clear to someone who lives here that a large fraction of people do not like them. The attacks that took place today are not the first. They happen, perhaps at a smaller scale, almost weekly. But it is a policy in Sweden that violence should not be reported. Central Stockholm and Uppsala, as well as many other Swedish towns, are accommodating immigrants from many countries, including Syria, Afghanistan, Romania, etc. One sees them on the streets. You can't go to a supermarket without seeing beggars often staying outside in the cold. Many people "help" them by giving them tips but even this is hard because the Swedish government adopted the policy of discouraging people from using cash, the intention being to force everyone use credit cards. Some beggars are now carrying credit card readers so they can accept credit card donations from people. But many people would rather not see anyone who looks darker than them. And since they cannot express their opinion openly, they put on a mask and beat street people up.

I know some people who work for the Uppsala city council who tell me that the phenomenon of attacking Syrian refuges camps is not uncommon. "I've never heard anything about it", I said. "You won't", they replied, "because the attacks are not reported." Apparently, only when something leaks out one finds out officially. Otherwise, it's hard to know what's going on. A few weeks ago there was this mass sexual attack in Cologne, Germany, from the other side: that is, by migrant people. Someone I know in Uppsala told me, around the beginning of the year, that similar things have been taking place in Sweden. "I can't believe it", I said. Again, the answer was "they are not reported". And, indeed, 2 weeks ago something leaked out. There were sexual attacks, by migrant youths but police did not make the information public. When the BBC found out they questioned the chief of the Swedish police who admitted that information is not released.

It happens both ways. Regardless of whether Swedes attack immigrants or the other way around, one cannot always find out: these attacks often don't make the news. Not by negligence; but by design.

In 2013, the now infamous Stockholm riots took place. A relatively high proportion of immigrants and second-generation immigrant residents, including a substantial number from Somalia, Eritrea, Afghanistan and Iraq instigated a mini-revolution by burning cars, throwing bricks, vandalizing, etc. Somehow, this was thought to be against the image that Sweden is portraying towards the outside world so it was not reported. When it leaked out, police declared it was terrorist groups. Although one may call such acts terrorism, it's not the kind that take place elsewhere. Apparently, the revolting migrants were expressing their frustration for their segregation and attacked innocent, of course, people. Just like in Paris suburbs a few years ago, at a smaller scale. As for segregation, it is rather obvious that many people who don't like typical Swedes are being kept apart. There is a neighborhood in Uppsala, Gottsunda, where they put immigrants. When we first moved to Sweden and were looking to buy a house we were explicitly warned not to go to Gottsunda. Such racist comments I thought existed only in Texas (and had experienced them). But Sweden, in some sense, is even more racist.

Back in 2011, when we had just moved to Sweden, there was this infamous mass killing in Norway by that human monster called Anders Breivik. The day after the killings, several people in Sweden started posting on Swedish newspaper sites, anonymously, their support for Breivik. I remember I got a call from Stockholm and was told to take a look at what they were saying. With the help of Google Translate, I read several of their comments and was appalled and scared. Good to know, however, I thought, that many people around me in Sweden support Breivik and would kill those whom they consider responsible for supporting immigrants. But my thought was quickly overturned: the Swedish newspapers decided to censor the readers' comments by deleting them and by closing their sites for a couple of days. They also created filters and other gadgets so that readers can't post anonymously (and, who knows, censor those who expressed their sympathy for Breivik).

Taking the train to and from Stockholm, one encounters some sad angry youth in neo-Nazi uniforms and tattoos: SS tattoos on their shaved heads. The reaction of passengers is to ignore them. I think they are scared, but I can't tell because they don't discuss it. I met Nazi demonstrations in Uppsala a few times. In 2010 or 11 there was this riot at the center of Uppsala by a bunch of angry young Nazis with pictures of blond men chasing black people. I approached one of them and asked him what's up. He said "we're against immigrants because they steal our jobs". I replied that "I'm an immigrant too and have the job of a professor in the University." I think I was aggressive and the young Nazi got scared. He replied  "it's only black immigrants we don't like. White Europeans are OK." "But I'm American", I said. He looks at me and says "It's OK, Americans are white Europeans." I didn't finish my sentence when a cop approached me and told me to get away.

And then, sometime later, we saw more riots of neo-Nazis, probably from the so-called "sverige demokraterna" party. The funny thing was that they had asked support of Greek Nazis from the equivalent "golden dawn" Nazi party. They brought them to Sweden for support!

The times are very fearsome. There is violence from all sides and it's rather clear that violence will escalate. I'd rather know than be in darkness. So I don't appreciate the censorship of information in Sweden. The Police view is that they should not "disturb" people by revealing that there was violence, rapes, murders, etc. But not all agree. It is silly and irrational not to know the truth. Take, for instance, the pre-war Jewry in Germany. Many of them were in denial that something bad would happen to them. Would it not have been better if they knew so they could get out while the could? When they finally found out what the true intentions of the Nazis were it was too late.

P.S. The latest response by Swedish government: Deport 80 thousand immigrants.  Previous response (4 weeks ago: fence borders.)


What measure theory is about

It's about counting, but when things get too large.
Put otherwise, it's about addition of positive numbers, but when these numbers are far too many.

The principle of dynamic programming

max_{x,y} [f(x) + g(x,y)] = max_x [f(x) + max_y g(x,y)]

The bottom line

Nuestras horas son minutos cuando esperamos saber y siglos cuando sabemos lo que se puede aprender.
(Our hours are minutes when we wait to learn and centuries when we know what is to be learnt.) --António Machado

Αγεωμέτρητος μηδείς εισίτω.
(Those who do not know geometry may not enter.) --Plato

Sapere Aude! Habe Muth, dich deines eigenen Verstandes zu bedienen!
(Dare to know! Have courage to use your own reason!) --Kant