Imablog

That’s the fancy schmancy word for solar power.

This month’s issue of Physics Today has (in addition to the blurb on social physics) a neat article on how to set up a small solar power system for your house to run things like the TV or other appliances. Even if you don’t have the skill to put one together yourself, the article is an interesting read that shows you what goes into a PV (photovoltaic) system and how they work. It’s not a comprehensive guide though, but is still very informative. The author emphasizes the fact that you don’t need to make your house fully dependent on solar (going off the grid). Even if the system you build only powers a few appliances, you have the satisfaction of being able to use power generated by the sun and not from some power plant somewhere.

From the article:

By offsetting electricity bills, properly sized grid-tie systems can recover the cost of installation in as little as 8 years in states with rebate programs—though 15 years is a more typical time frame. Small standalone PV systems will likely not recover installation costs at today’s energy rates: Many components are necessary or desirable whether the system is large or small, but they cost similar amounts in either case. Still, few PV owners are motivated by purely economic reasons. That couldn’t be more true for me. I opted to build a small standalone system to power my modest living room, which includes a TV, DVD/VCR, stereo, and lighting. My goal was to learn the ins and outs of a personal PV system, characterize performance, and experiment with various configurations. The sense of satisfaction I get when watching a movie or reading a book using stored solar energy is reward enough.

We physicists are getting into everything. Now, it seems there’s something called ‘social physics’. There must be something to it because so far this week I’ve come across two articles in this ‘social physics’ field.

The first paper is related to food, specifically the staying power of cultural and national dishes.

Abstract:

Food is an essential part of civilization, with a scope that ranges from the biological to the economic and cultural levels. Here, we study the statistics of ingredients and recipes taken from Brazilian, British, French and Medieval cookery books. We find universal distributions with scale invariant behaviour. We propose a copy-mutate process to model culinary evolution that fits our empirical data very well. We find a cultural `founder effect’ produced by the non-equilibrium dynamics of the model. Both the invariant and idiosyncratic aspects of culture are accounted for by our model, which may have applications in other kinds of evolutionary processes.

The second article from the July issue of Physics Today. It’s a more general news article about how social networks are starting to attract physicists and mathematicians.

From the article:

Researchers studying self-organizing social networks look at how links are formed between individuals, whether some individuals or nodes are better connected than others, and the collective action or behavior of the entire network. In the past social scientists relied on surveys and questionnaires, but on the Web “social behavior is self-documenting—it leaves traces behind,” says Microsoft research sociologist Marc Smith, who studies and designs improvements for social online applications.

Some condensed-matter physicists are drawn to social network modeling because it is similar to a many-body problem, says Huberman. Like spin-glass materials that have disordered and unpaired magnetic spins, individuals have conflicting interactions with their neighbors, and their uniqueness leads to disorder, says Université de Paris-Sud physicist Marc Mézard. It’s a patent from Mézard’s spin-glass theory work that is now paying off for Microsoft: He, Chayes, and collaborators are using that patent to solve optimization problems such as sending messages from one node to others, bypassing intermediates.

See, there’s physics in everything!