Philosophy

Small particles take indeterminate paths

Yesterday, in the New York Times, Brian Greene wrote a very helpful piece on quantum theory. Here's the best part:

The very idea that an electron, or a photon, or any other particle, travels along a single, definite trajectory from here to there is a quaint version of reality that quantum mechanics declares outmoded. Instead, the proponents of quantum theory claimed, reality consists of a haze of all possibilities - all trajectories - mutually commingling and simultaneously unfolding. And why don't we see this? According to the quantum doctrine, when we make a measurement or perform an observation, we force the myriad possibilities to ante up, snap out of the haze and settle on a single outcome. But between observations - when we are not looking - reality consists entirely of jostling possibilities. Quantum reality, in other words, remains ambiguous until measured. The reality of common perception is thus merely a definitive-looking veneer obscuring the internal workings of a highly uncertain cosmos.

Greene reassures the reader that this effect is only present with respect to very tiny particles. The question, "Is Fido in his doghouse?" has a definite answer.

Today, the New York Times reported that congressional outrage had killed a program to study the effects of pesticides on babies. The best part of that article:

A recruiting flier for the program, called the Children's Environmental Exposure Research Study, or Cheers, offered $970, a free camcorder, a bib and a T-shirt to parents whose infants or babies were exposed to pesticides if the parents completed the two-year study. The requirements for participation were living in Duval County, Fla., having a baby under 3 months old or 9 to 12 months old, and "spraying pesticides inside your home routinely."

To find out whether pesticides are harmful to babies, you have to encourage parents to keep using pesticides in their homes for two years, while repeatedly asking the question: "Are these chemicals damaging my baby?" I hope they gave them a really good camcorder, with 10X zoom.

As Greene says, the quantum effect is only manifest in really small things.