Saturday, November 17, 2012

Thermodynamics using Earth-centric Units

While the trend in science has been to point out the obvious fact that the Earth is not the center of the solar system or the universe, over the last few decades there has been a trend in the engineering community of trying to teach thermodynamics with an Earth-centric focus. The new quantity that has appeared in this Earth-centric thermodynamics is called exergy.

Exergy is defined as the maximum amount of useful work that can be generated by bring a non-equilibrium system into equilibrium with the Earth's environment, i.e. bringing the system to the same temperature, pressure and chemical composition of the Earth's environment. The Earth has an enormous amount of stored exergy (fossil and nuclear fuels) as well as an enormous amount of exergy supplied to it in the form of light from the Sun. In some ways, the definition of exergy is completely arbitrary because the amount of useful work that can be obtained in bring a system into equilibrium with Earth environment is always less than the amount of useful work that could be obtained by bringing a non-equilibrium system into equilibrium with a ~0 K vacuum. Exergy is a really useful engineering quantity, even though it has no scientific meaning (since somebody living on a planet with a different temperature and/or a different atmospheric pressure/composition would measure a different value of exergy for the same exact enclosed system.)

But since exergy is such a useful definition for power plant engineers, this begs the question: are there other ways that we can modify the way we teach thermodynamics so as it make thermodynamics easier to learn and to apply? (Note that this is also one of the reasons why I'm in favor of having a currency that keeps the average price of purchasing useful work a constant. It makes it significantly easier to teach and to learn thermo-economics, i.e. that currency represents your capability to purchase useful work.)

Monday, November 12, 2012

Death of Supersymmetry: Experimental Evidence against the Theory

Many of you may have already heard about the very recent evidence against the theory of supersymmetry (i.e. that there are massive super-particles for every particle found so far. In supersymmetry, for every boson there's a super-symmetric fermion, and vice versa. Supersymmetry is also an underlying component of most string theories.)
Here are links to a few articles in the public media regarding the latest evidence against supersymmetry:
BBC news article
New Scientist article

Here's a link to a recent article I wrote on the Death of Supersymmetry and String Theory. In the article, I mentioned that I would start adding more of the details about the experimental evidence against supersymmetry. Rather than just edit that article, I figured that I'd just make a new article and link to sites with the latest evidence against supersymmetry.

http://www.math.columbia.edu/~woit/wordpress/?p=5013
BBC news article from Nov 2011 on similar topic
http://www.math.columbia.edu/~woit/wordpress/?p=5272
http://www.math.columbia.edu/~woit/wordpress/?p=3937
http://www.math.columbia.edu/~woit/wordpress/?p=4171

Sunday, November 4, 2012

Summary of "Self-replicating economics"


Last week at work, I unfortunately had to sit through a presentation  by an economist outside our company who tried to give us a 'Crash Course in Economics for Engineers.'   Whoah!

Have you ever watched or sat through a presentation by an economist and had the thought jump into your head, "This person has just completely talked themselves into a circle. They started out the sentence explaining why inflation is good, and by the end of the sentence, they finished with how deflation raises the value of the dollar and, hence, deflation is good."  Note: it scares me when economists ignore the self-referential nature of economics calculations. In general, if you try to ignore self-reference, it will show up and make you look like a fool. (For example, thinking that government spending has a multiplier effect greater than one.) It's better to just include the self-reference into the calculation from the start. Physicists learned this years ago when they asked the question: what is the charge on a bare-naked electron if there were no vacuum polarization? Chemists had to ask this question when they were studying the collective bonding effects in polar liquids like water. In both cases, scientists resorted to renormalization theory to remove the infinities that would pop up. Every economist either needs to understand renormalization theory or needs to take a few courses in biology, i.e. the study of self-replication.

Here's what I supposedly "learned" in that presentation:
(1) The business cycle is cyclic, and the next peak will be in 2015.    (Don't worry. The business cycle is not predictable and is not sinusoidal.  Many people have shown this, but if you want proof that there is no such thing as a business cycle, check out my Frequency Analysis graph in one of my earlier posts. There is no one frequency that stands out above the rest, except the junk at low frequency due to the overall, non-cyclic trend of increasing GDP. So, don't believe anybody who predicts for you when the next GDP peak will be, based off of when the last peak was and based off of some seven/eight year cycle.)
(2) Economies fluctuate about a steady-state growth rate. Steady-state growth is the equilibrium point and oscillations about this point are nearly perfectly sinusoidal.   (Don't worry. This is false as well. There is no such thing as the 'steady-state growth rate.' And as mentioned above, oscillations in the real world occur at every conceivable frequency.)
(3) The economy is a closed system because the money just keeps on circulating, so there's no need for a Federal Reserve to keep printing money.   (There's at least one problem with these statement. First, the economy is not a closed cycle. It's like an ever expanding spiral in which useful work is used to make more useful work. Second, the amount of money in circulation should ideally increase as the spiral gets bigger and bigger, i.e. as we make more and more power plants. Money is simply a way of determining who gets to use what percent of the useful work being generated from power plants. Theoretically, it shouldn't matter how much money is in circulation, but in practice, most people prefer that the prices of items they buy remain constant or decrease with time, while at the same time, they prefer that the dollars in their bank accounts increase with time. Ideally, there would be a non-profit agency within the government that forces the Treasury to print or remove enough currency from circulation in order to maintain 0% to 2% inflation in the average price of useful work. Right now, that agency is Federal Reserve. But it isn't really a part of the government and it hasn't been doing a good job over the last six years because there are some confused economists on the Board of Governors who think that the Federal Reserve can decrease unemployment by printing money and giving that money to the government and Wall Street. While the Federal Reserve system in the US has some major flaws, these flaws could largely be fixed by adopting a rule-based system of when to print or remove money from circulation, as has done by many countries, including Germany before the euro.)

Given the fact that economics can be an extremely difficult to teach, the goal of this post is to summary the main points I've made over the last few years in the area of "self-replicating economics," i.e. the study of human-designed system that can self-replicate nearly-independent of biological systems. My hope is that economics can become a fairly easy subject to teach if instructors focus on examples of small, self-replicating systems.

For example, we have designed "oil/gas well, power plant, steel mill" systems that can self-replicate nearly independently of other systems. In other words, we can drill wells, build steel mills, build factories, build vehicles, build turbines, and build power plants in ways such that the whole system can self-replicate and grow. Unfortunately, the growth rate of this "oil/gas well, power plant, steel mill system" has been decreasing slowly over time (despite increases in technological know-how of the people designing the systems) because the increase in technical know-how has not off-set the increase in direct and indirect taxes on this system as well as the fact that the oil/gas we drill for is often at lower and lower depths and that the systems we design now are often more complicated in order to reduce the damage on biological self-replicating systems.

I think that it's important to focus on and teach all of the main components of a system that can self-replicate independently of other systems. In other words, if you are going to teach the subject of economics, don't focus just on small parts of the system, such as hamburgers and soda. People, hamburgers and soda don't represent a full system that can replicate. A full system might be:  traders, homes, clothing, police, politicians, cattle, goat, blacksmiths, farmers, civil servants, teachers, chefs, horses, etc... Since the smallest set of items in a self-replicating system that includes human is probably really large, it might make sense to start with simple mechanical systems that are complete and self-replicating. For example, in prior posts, I've discussed possible examples of human-designed self-replicating systems, such as a self-replicating wind turbine/factory systems and auxons, which are self-replicating solar panel/factory systems. It's easy to talk oneself into a circle if you don't study the entire self-replicating system. For something as large as the world economy, I understand that it is difficult to see what's really going on (i.e. self-replication), so what I normally try to do when teaching economics is to simplify the economy down into its main components so that one can see that economic growth is due to the fact that he have design "oil/gas well, power plant, steel mill, turbine factory, electronic equipment factory" systems that can self-replicate. Before we designed these thermo-mechanical systems, economic growth rates were pretty much confined to population growth rates (of plants and animals in the system.) The goal of the remainder of this post is to summarize what I call the field of "self-replicating economics," which is the study of complete, independent systems that can self-replicate and grow.