From "Seven Attempts at Liquifying the Self" by N. Schultz in his Experiment in Private Self-Consciousness Heisenberg’s Uncertainty Principle is rightly seen as the first 20th Century result that puts an absolute limit on what can be measured, and, by implication, known about the world. The principle states that complementary variables such as the position and momentum of a particlecannot be simultaneously discerned to any arbitrary degree of precision. The principle is often illustrated with a standard thought experiment: in trying to observesmaller and smaller objects, the wavelength of the light used to"illuminate" the object must use a smaller and smaller wavelength, i.e. photons with larger and larger energy. This large energy then gives the particle to be sighted some momentum change that makes it impossible to determine the particle’s momentum. This explanation, referred to as the Gamma-Ray Microscope thought-experiment, is widely used at many educational levels. See the Discovery Education site for Grades 9-12, for example. A more interesting use of the illumination examplecan be found at the Fly in the Honey blog, posted by Mary (that’s all the info I can determine about the author other than I believe that sheis a teacher), where she claims to be very poor in math and science, yet is incredibly moved by the standard conclusion of the Uncertainty Principle: "the very act of observation changes the object being observed."

The Gamma-Ray Microscope thought-experiment, amythological story that began with Heisenberg himself, has been de-valued as a good example of the principle. It turns out that the world is much weirder than that pictured in the thought-experiment. (I will explain this in a future post.) Regardless, it does not diminish from the fundamental idea that observation affects the observed in fundamental ways that cannot be eliminated with more precise and careful instrumentation andmethodology.

On one hand this is a very deep concept; on the other it appears to be tautological, especially when both the experimenter and experimental subject are conscious agents.

The idea of observation implies an observer, and usually a conscious one. (For some, the consciousness of the observer is an essential component of the act of measurement in quantum physics - specifically in the notion of wavefunction collapse, a staple of the so-called Copenhagen Interpretation of quantum mechanics.) The object being observed is usually not conscious - except if you consider the feline consciousness of Schrödinger’s Cat (Click here for a recent poston Copenhagen and The Cat.) Yet what happens if the observed is conscious?Certainly knowing that one is being observed can cause a conscious or unconscious change in behavior.This is obvious. So the act of observation definitely changes the observed. What’s so earth-shattering here?

Onespecial trait ofconsciousness is the ability to function and analyze on meta-levels. Maybe Heisenberg’s Principle is more essential ona level that allows for consideration of the consciousness of the observed. Or maybe the way to get at the effects of the observed being conscious isto design an experiment that deliberately attempts to change the subject of the study through the act of observing.

A recent study by Steven Heine, a psychologist at the University of British Columbia, and colleagues has indirectly looked at this question via an intriguing experiment. In the study two groups of womenwere given difficult math tests. One group was toldof a theory that claimspositive math performance is genetic, with the controlling genes on the Y-chromosome, i.e. women aregenetically pre-disposed to do worse at math than males. The second group were told of a theory that the differing abilities of male and female mathematical performance was primarily based on their upbringing. Thus the two groups represented basic nature vs. nurture samples. The wicked twist to the experiment is that neither theory is true, so the women are being manipulated for the purpose of the study.

Amazingly, the women who were told of the genetic theory did poorer on the math exams! According to Heine the reason for this isbest explained by consideringthe "nurture" group:"apparently, hearing that personal experiences might cause poorer math performance among females enabled women to conclude that the stereotype might not apply to them."

So the Heisenberg Principle is much deeper than expected for conscious subjects, and much more interesting. Here we have a case of the subject being observed believing something about the conscious intentions of the observers, i.e.the women believed that the experimenters were testing out the theories of math differences in men and women. Just "knowing" what theory was being tested was enough to change their behavior (which in this case is being treated as equivalent to performance). Of course, the theories here weren’t reallyvalid theories, but the repercussions arehuge: Not only does the act of observation often change change the outcome of the experiment (with conscious subjects) - just knowing about the experiment, and what might be in the minds of the experimenters is enough to change the behavior of the subjects of the experiment!

Somewhere Heisenberg is spinning in his grave, although if we try to observe this he would most likely not be there….

Note: This post was inpired by Steven Heine’s Nov. 5, 2006 article in the Philadelphia Inquirer titled Scientific theory affects psyche.