Galactic cycles might cause mass extinctions

University of Kansas Professor of physics and astronomy Adrian Melott has written a fascinating and accessible piece in Seed magazine noting a correlation between the oscillation of our solar system and an apparent 62-million year cycle of mass extinctions visible in the fossil record. Evidence seems to indicate that, as the solar system 'bobs' up into the Galactic north of the Milky Way's disk plane, it's bombarded with extra cosmic rays originating from the local supercluster. Cosmic rays can contribute to mutation (usually deadly - superheroes notwithstanding), as well as degrading of the ozone layer - both nasty effects which could, just conceivably, trigger mass extinctions on a (cosmologically) regular basis.

In case you were wondering...

about the time lapse between the last entry and the one previous, the last month of the school year is ever a time of frolicsome (and not-so-) chaos. My dear blog suffered massively from neglect as I spent my time in such pursuits as grading large piles of end-of-year papers and projects, meeting bureaucratic deadlines, and so forth. Now that I've got the opportunity to spend time somewhere with wireless internet and no firewall, I intend happily to blog away once more, so that you, dear readers, may be informed about the fascinating tidbits of classical literature, philosophy, technology, and popular culture which I happen to dredge up from trawling the web.

Fishily yours,

Dr. P.

Networking and its critics, ancient and modern

The following is an excerpt from an article that ran in the Boston Globe on June 14, adapted from Duncan Watts in the Harvard Business Review. He's making the point that the more complex a system becomes, the less predictable - and sustainable - it is, and that this is an inherent feature of its very complexity:

It may be true, in fact, that complex networks such as financial systems face an inescapable trade-off - between size and efficiency on one hand, and global stability on the other. Once they have been assembled, in other words, globally interconnected and integrated financial networks just may be too complex to prevent crises like the current one from reoccurring.

It is interesting to recall and compare Aristotle's criterion of the polis eusunoptos in both the Politics and Nicomachean Ethics - the ideal city should be able to be 'taken in at one glance' - at least, not too big to be wieldy. Aristotle not only considered an obvious target - the monstrous Babylon, in which, anecdotally, one part of the city did not know it had been conquered in war until some days had passed - but even criticized Socrates for proposing a city with 5000 male citizens.