Knowing and Making

Niklas Blanchard seems to have a sideline as a graphic artist alongside his prolific blogging. He's been working on a series of unauthorised logos for blogs, covers for Scott Sumner's book and similar bits of miscellany. I was flattered to discover that I'm one of his targets beneficiaries, with this galactic tribute  to my liquidity-trap-believing, Krugman-sympathising, physics-quoting bleeding-heart liberal blogging habits. It's very nice if a bit twisted! Click through and have a look. Certainly more appealing than my previous  surprise compliment. Update : Now with official permission to embed the image:

I'd like to write a full article on each of today's links, but I may never get around to it. In the meantime, you may have your own conclusions to draw: Tim Haab has a good defence of economics as a mathematical discipline. While the particular maths we have to use will evolve, as we incorporate more psychology, theory of organisations and financial institutions into the orthodoxy, economics will and should still use lots of mathematics - because that's the only way we can build and apply successful models. In this review of Create Your Own Economy , Henry Farrell starts to build an argument that the internal mental orderings which add value to our own lives, can also add value to other people's. My own review (not out yet) touches on the converse idea - can ready-made (or at least part-cooked) mental orderings be provided to us as a service? A mini-Easterlin paradox from Stephanie Flanders : as a country, are we more interested in comparative measures of GDP (against ...

On Radio 4 this morning is an amazing programme exploring some really deep and technical issues about quantum theory and the nature of reality in physics. Amazingly in that they are brave enough to broadcast it at a time more associated with The Archers . Amazing in that the level of discussion is one that would challenge most physics and philosophy graduates, and they let it loose on a mainstream audience. I'm impressed. But then I read Robert Peston's latest post about China , and it became even more resonant. That old question is asked: who or what is to blame? In particular, was the financial crisis caused by excessive borrowing by Westerners or excessive lending by China? The thing is, of course, that neither of those things could happen without the other. That makes it impossible to really debate whether saving caused lending or vice versa, let alone which one caused the financial crisis. And that's where I am reminded of the methods of quantum physics and how we sol...

Those unfamiliar with theoretical physics may not have come across one of the most beautiful derivations in all of science: the results of statistical thermodynamics . I would like to introduce them to more people, not just because they are an intellectual tour de force in themselves, but because they hold very interesting lessons for economists. In short, these results extrapolate from some very simple rules about low-level structure and statistics to derive powerful results about the behaviour of the whole system. This is also a common theme of economics. General equilibrium results start from basic assumptions about rational market agents and efficient prices, and derive a result about the efficiency of the whole economy. The problem is that if the original assumptions are wrong, the results are wrong. And experiments show that the assumptions are indeed wrong. Economics has two possible directions from here. It can change the assumptions and recalculate the consequences. An appeal...

The Telegraph thinks America produces enough electricity to power one lightbulb for every 30 citizens. Huh? This article (about a powerful laser) says it produces "...energy equivalent to 1,000 times the amount produced by America's national grid, or more than 10 billion times more than an ordinary household lightbulb." A bit of simple arithmetic indicates that the national grid can power 10 million light bulbs. Which, with 300 million people, means it must be pretty dark most nights. Actually, the laser has a power of 500 trillion watts - which means nearly 10 trillion  60-watt lightbulbs. But if you let loose on science stories journalists with no instinct for arithmetic... The crucial question that goes unanswered by the article is, of course: will it create a black hole that could destroy the Earth? I say we should shut down all scientific research until we are sure. As Brad DeLong might say: " Why, oh why, oh why... "

Jonathan Amos at the BBC has an article about a car that's planned to achieve a speed of 1000 mph: "...at its maximum velocity, the pressure of air bearing down on its carbon fibre and titanium bodywork will exceed 12 tonnes per square metre." Wow, that sounds pretty heavy. But normal atmospheric pressure on a square metre of your ordinary Ford Fiesta, or indeed your skin (if you have a square metre of that) is about 10 tonnes! Careful in copying what the press releases say - it may not be as exciting as it sounds.