Friday, July 9, 2010
The only problem we could solve exactly was the hydrogen atom. No matter,
we just built the universe out of hydrogen atoms, using quantum
electrodynamics (QED), and few approximations to take care of the other
stuff, it all worked great -- until now. A group led by R. Pohl at the Paul
Scherrer Institute in Switzerland has measured the Lamb shift in muonic
hydrogen, in which the electron has been replaced by a negative muon.
That should give a far more accurate measure of the proton width. The
problem is it doesn't agree with other methods of determining the proton
width. It's too early to speculate about what the problem might be, but I
find it reassuring that there are still foundational problems.
Last week we reported that Michael Mann, the Penn State University climate
scientist who played a key role in alerting the world to global warming,
was exonerated by the University in the climategate controversy that broke
in December http://bobpark.physics.umd.edu/WN09/wn121809.html .
Wednesday a British panel exonerated the members of the Climate Research Unit at East
Anglia University in the UK. However, the scientists had failed to uphold
the standards of openness on which the credibility and influence of science
is grounded. Everyone involved has now been held accountable for their
actions, except the unknown hackers who broke the law. They must have
imagined the e-mails would set off an explosion, but it was in the end a
barely audible "pop." So everyone has been cleared except the unknown
hackers that selectively leaked the climate scientists e-mails.
The action of San Francisco requiring radiation exposure warnings on cell
phones was justified as precautionary. That sounds reassuring, but wait
a minute: The precautionary principle states that, in the absence of a
scientific consensus the burden of proof that an action will not cause harm
to the public or to the environment falls on those taking the action. Im
inclined to think the first law of thermodynamics is a scientific
consensus, but some biologist keeps sending me angry letters saying
conservation of energy doesn't apply to biology. In a Comment to the London
Free Press last Friday the same biologist wrote: "Most importantly, the
mere fact that the cell phone booklets provide warnings to keep the device
at a certain distance from the body, is itself one of the strongest
indications that the radiation emitted is not totally harmless." So cell
phone makers, hoping to calm hysterical critics by adding a little space,
are now accused of knowing the terrible truth all along. Hmm, maybe it
doesn't pay to be too cautious.