Friday, September 25, 2009
Last week, Senate hearings were held asking whether cell phones cause brain cancer. Brian Walsh, writing for Time, described the outcome as "inconclusive." A
collective groan rose from the nation's physicists. "Not again?" It's been almost 17 years since David Reynard, whose wife died from brain cancer, was on
Larry King Live. Reynard was suing the cell phone industry. He said his wife, "held it against her head, and talked on it all the time." That was enough for
Larry King.
However, all known cancer agent act by breaking chemical bonds, producing mutant strands of DNA. It would be like suing me for hitting someone with a rock thrown
across the Potomac River. George Washington is said to have thrown a silver dollar across the Potomac. I can't throw that far, and microwave photons can't break
chemical bonds. Not until you get up to the near ultraviolet, about 10,000 times more energetic than microwaves, are photons capable of causing cancer
http://jnci.oxfordjournals.org/cgi/content/full/93/3/166 .
It seemed to many of us that the culture police must have outlawed any mention of Earth's ultimate problem. The word "population" is now rarely mentioned by the
media. This week in Nature, the population problem is given a new name. "A Safe Operating Space for Humanity" is the Feature in today's issue. It's an edited
summary of a longer paper available at the Stockholm Resilience Centre. The study was led by Johan Rockstrom. To facilitate debate and discussion, Nature is
simultaneously publishing a number of linked commentaries from independent experts. It may be the most important project Nature has ever undertaken. Numerical
boundaries to human activity beyond which our planet would risk not recovering are:
anthropogenic climate change, ozone depletion, ocean acidification, biodiversity, freshwater, the global nitrogen and phosphorus cycles, and change in land use.
In the case of anthropogenic climate change and human modification of the nitrogen cycle we may already have crossed the boundary. It could be argued that the
boundaries are simply surrogates for the overriding problem of reducing human population.
According to NPR, Iraqi authorities have spent millions of dollars to outfit checkpoints with handheld devices that point to explosive materials. Many U.S.
officials scoff that it's about as reliable as dowsing for water, but others think dowsing works too. In fact, the Pentagon has bought a few
http://bobpark.physics.umd.edu/WN98/wn092598.html .
The Augustine summary was mostly advice on living within your budget. The summary advises extending the life of the ISS, but not because any important discoveries
are likely. Rather, as the Economist put it, "spending a quarter of a century building something and then scuttling it looks bad, even if the science that's
been done on board could be written up on the back of a postage stamp."
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