Title: Q & A: Observer Effect? | Department of Physics | University of Illinois at Urbana-Champaign
Headings: 
Q & A: Observer Effect?
Follow-Up #1: quantum
Follow-Up #2: observation and light
Follow-Up #3: measurement and consciousness?
Follow-Up #4: free-will?
Follow-Up #5: confusion between the uncertainty principle and the observer effect
Follow-Up #6: Quantum for the non-scientist
Follow-Up #7: Unconscious observers
Follow-Up #8: Bell's Inequalities and free will
Follow-Up #9: free will and quantum mechanics
Follow-Up #10: what collapses wavefunction?
Follow-Up #11: What causes quantum interference loss

Content: Q: As a follow up to the previous answer, I'd like to share something I found interesting. If one defines free will as something like "non-deterministic", one can prove from three simple axioms that if you wish to claim we (experimenters) have "free will", then we must conclude electrons have "free will" as well. http://en.wikipedia.org/wiki/Free_will_theorem  It is an interesting way to demonstrate the "measurement problem" in quantum mechanics, for in the traditional Copenhagen approach the evolution of a system is completely deterministic except for a measurement. If it turns out all of physics can be explained with the appropriate choice of lagrangian, can we really have the freewill to choose a random measurement? - Kevin M (age 29)
Urbana, IL, USA
A: Thanks for the interesting link. Just to expand on a point mentioned in passing in that article, there is a strong distinction between the indeterminacy described by the theorem and the traditional concept of free will. Readers should be forewarned that what follows somewhat spills over the edge of physics into philosophy. There are serious reasons (including the violation of the Bell Inequalities) to conclude that the sort of events described by quantum mechanics are "free" in the sense that no prior fact about the universe can tell us which outcome we will observe.