19 February 2015

Coulomb's law

About a year ago, I discovered a very interesting short video by Richard Feynman responding to the question of what happens when we hold two magnets next to one another. His answer was brilliant.

Recently, I came across a video from the 50s where a physicist is conducting experiments trying to explain electrostatics and, more precisely, Coulomb's force. What is very interesting is that he doesn't merely present facts, but also argues, from various points of view, trying to convince the listener that the force must depend on the distance r between two charges as a linear function of 1/r2 (and linearly on each charge). The argument, especially towards the end, is not dissimilar from that of a mathematician who is trying to explain Potential Theory and Laplace's equation. In the end (skip to 17'22'' if you wish), we realize, with a bit of thinking, that a lot of the things we see in the experiment are merely outcomes of geometry and the fact that we live in a 3 dimensional space (this is an experimental observation that works well!) where distances obey the Pythagorean theorem.

I found out that the physicist is Eric Rogers. The video was intended to be for secondary schools. These days, one can find students of electrical engineering who do not understand electrostatics, students of mathematics who do not understand what potential theory has to do with physics, and educators (they are called pedagogues--and, as I have explained, they form a modern type of plague) who insist that education is independent of the discipline. Not that there aren't universities that teach properly and students who understand a lot, but this species (those who strive to understand and, hence, to explain) is becoming rarer and rarer.

18 February 2015

Another very interesting statement by Yanis Varoufakis

Asked about his view on Economics, he said:
‘I found it such a morose subject, so bone crushingly boring, so much reliant on third rate mathematics. Why study inane metamorphoses of third rate mathematics when I could study first rate, aesthetically pleasing, ideologically unproblematic mathematics? So I immediately transferred to the School of Mathematics.’
Well, of course, I couldn't agree more. I'm not too familiar with economics departments, but I am familiar with what's going on (in Europe and in the US) in many "applied" departments of the kind that, whereas they require mathematics for their existence, they don't teach mathematics. Rather, they transform mathematics into a boring, stupidly taught, subject that it becomes a joke. Whole departments exist and survive on the promise to the students that "everything is easy" and that "they won't have to suffer" but all they have to do is "pay the fees and get a degree". It is the case in computer science, in statistics, in engineering, in business and I'm sure it is the same in economics. And when they graduate and realize they have learned nonsense, many of them start wondering why. I've seen their emails, I've heard them speak, in at least 2 continents.

The situation suits well, for the time being, not just the students who just want to get a piece of paper (a degree), but also those professors who don't want to do work hard. They assume that what they themselves learned in their college days is sufficient for the years to come. After a while, they learn some mantras by heart and just recite them. Without too much thinking. Many many teachers act like this. And, of course, the students who want to ask the why and the how will find their courses morose. The situation is also convenient for European university administrators who, a few years ago, came up with an insane theory that all universities should be offering equivalent education, no matter where they are located or who is hired by the universities. It's a self-sustaining situation. I used to think that, certainly, teachers know the subject they are teaching. I've been proven wrong time and again.

Now, having said that, it seems to me that the education policy of the government that Varoufakis is representing is not doing much sensible for universities. Rather, they seem to be resorting to the tactics of pleasing the masses. For their own reasons.

4 February 2015

Some very rational quotes from the new finance minister of Greece, Yanis Varoufakis

The idiosyncratic ways of the new minister, Yanis Varoufakis, have freaked some out. Several people are concerned with the fact that he's not wearing a tie or that he rides his bike. But he has made some extremely rational points. Time will show whether he will live by them or whether these are temporary caprices (I hope not).
Even in universities where I've lived all my life, I've always believed that  any colleague of mine who wanted to be head of department or dean should be disqualified immediately because you should only be doing this reluctantly as a public service. (See here.)
 How absolutely right! Why would anyone want to be an administrator puzzles me. Isn't there anything more interesting to do than speaking to the bureaucrats? For example, have you never wanted to have some free time to learn something new (e.g., constructive set theory)?
My greatest fear, now that I have tossed my hat in the ring, is that I may turn into a politician. As an antidote to that virus I intend to write my resignation  letter and keep it in my inside pocket, ready to submit it the moment I sense signs of losing the commitment to speak truth to power. (See here.)
This should be the rational response of anyone taking on unpleasant jobs, jobs in which lies are more important than anything else.
When one enters politics there is a very distinct danger that one may become a politician and that danger freaks me out because when I'm having a discussion with a normal person the whole point  is to learn from them and hopefully for them to learn from me, but when two politicians talk, the whole point is to undermine one another and to learn absolutely nothing from one another. If that happens to me please shoot me. (See here.)
To learn? What an idea! I've never heard this concept from a politician. Indeed, typically, politicians, especially in Greece, have been interested in stealing money, in ensuring a big pension, in ensuring their re-election. But never to learn or teach. What a novel thing to hear from a ... minister of finance!

P.S. And I just remembered this article I wrote 3.5 years ago regarding crises and bankruptcies in recent history.

18 December 2014

Dying in Sweden during the summer is not advisable

One thing that happens every summer in Sweden, especially after the so-called mid-summer day, is that the country closes down. It is very hard to do anything during the summer, from fixing your car to seeing a doctor.

But even dying is not advisable during the summer.

Why? Because there is nobody around to bury the dead body.

Here is the story: three years ago, the (Swedish) husband of a woman (whom we know) died suddenly in the middle of the summer by a wasp sting. This was very unfortunate and very sad. Very unexpected also. Indeed, some people may die from insect venom anaphylaxis (severe allergic reaction). These fatal allergic reactions frequently, but not always, occur in people who have had a previous allergic reaction to the same type of insect.

Once the first shock passes, the dead person's wife tried to arrange for a funeral.  Funeral offices abound in Sweden and, as I explained in an earlier posting, they have a very different look than in other countries because they display their products (coffins, urns for ashes, etc.) in their windows. In the previous posting, I also analyzed the concept of a funeral office magazine which is issued at the hefty price of 9.50 USD. We receive it for free. And I described its contents. Therefore, funeral offices exist and are very well-organized. They even produce software for the management of death-related operations. (See my previous posting.)

However, they apparently all (or almost all) close down during the summer, so much so, that the unfortunate woman could not find any funeral office in Stockholm or in a nearby area in order to bury her husband. She searched and searched and nothing was available. Instead, she was told to wait until September, to have the body frozen until they reopen in September and resume business as usual. To be accurate, I believe that there are some funeral offices open but they work at a very low pace during the summer so they're fully booked. Hence the waiting time.

It appears, therefore, that dying during the summer should be avoided in Sweden. Or, if one expects to die, he or she should make a reservation with a funeral office a few months in advance. Perhaps this is why the funeral office magazines are being sent out: as a reminder to reserve a spot should you plan to die during the summer.

14 December 2014

Funeral office magazine sent to us for free

Back in 2011, I noticed that some funeral offices in Sweden are very different from funeral offices in any other country I'm aware of. That is,  funeral offices here advertise their products: coffins, cremation urns, etc.

Another interesting thing is that funeral offices produce magazines. For four years now, we've been receiving, at home, magazines from funeral offices, at least biannually. The latest magazine just arrived a couple of days ago and is a special issue for the Christmas season. It is called memento:
Translation: Top left: from the funeral office.  Title: The Nordic essence; mythical creatures from the graveyard. Bottom right: Price 70 Swedish Crowns (approximately 9.50 US dollars)
So, I guess, we are lucky! We get the magazine for free and don't have to pay.

Let's take a look at what's inside. It advertises coffins of special elegance. A picture (bottom right) shows the craftsmanship going into the material on which the dead body will rest, while another picture (top right) shows a path converging to infinity (of presumably metaphysical/religious significance)--the interpretation is left open for the reader.
A new age coffin, the path to eternity, and craftsmanship of the coffin's velvet interior
It also advertises hearses, that is, automobiles carrying the coffin with the dead body to the burial place. This particular company prides itself in being "a new generation of building concepts" and, in addition, offers extra long hearses. As this chart shows, Swedes are typically tall (and taller than in the past), so funeral offices with long hearses are doing better businesses. Interestingly, however, the taller a Swedish man is the less likely he will commit suicide, according to this paper.
Translation: Extra long hearses have been designed to facilitate your working day. High comfort and smart solutions provide a good working environment
The main story of the magazine is about mythical creatures that one can encounter in Swedish cemeteries. They look like this
They are called "myling" and are ghosts of children who died before they had a chance to be baptized.

The magazine also contains an article about death and art, photographs from graveyards, and an article about cancer
Death art
A photographer who sees death all the time
Dead bodies as art
Translation: Much remains even if the cancer is gone.
Interpretation: So be ready to die, we'll take care of you
and an ad about a computer program, "eulogica", for managing death operations:
Software for the management of death operations

Persons portrayed in this magazine often have their look of dead on their faces. This lady seems to be smiling at us in a very sinister manner
He he he ...
while this one's face is almost grey (I don't know if the color can be accurately reproduced, but it's true--welcome to take a look at my copy of the funeral magazine), as if she's about to die or just resurrected from the dead, like Lazarus.
Translation: We help you [so that when you die you won't have to carry your own coffin]

And, of course, since we're so close to the Festive Season, there is even a Santa Claus acting like everybody else around: typing away on his computer.
Translation: Merry Christmas and Happy New Year
This time of the year, there is just darkness around. We never have sunlight (5 hours in total during November). And there are no lights either. Strangely enough, lots of public places dim their lights down when darkness hits. I don't go to restaurants because I have trouble reading the menu--it is so dark.In general, it feels as if we're playing along with Bengt Ekerot in Ingmar Bergman's Seventh Seal:
If you ever wondered what Bergman's films mean, you haven't spent much time in Sweden
Fortunately, nobody committed suicide this year (as opposed to last year) at the university.


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