Posted: Oct 07, 2011 3:32 pm
by twistor59
Teuton wrote:"Was the world wave function waiting for millions of years until a single-celled creature appeared? Or did it have to wait a little longer for some more highly qualified measurer—with a Ph.D.?"

(Bell, J. S. "Quantum Mechanics for Cosmologists." In: J. S. Bell, Speakable and Unspeakable in Quantum Mechanics, 2nd ed., 117-138. Cambridge: Cambridge University Press, 2004. p. 117)


That quote is talking about the measurement process, sometimes misleadingly called "wavefunction collapse". The generally (but not universally) accepted modern view on this is that it takes place via the process of decoherence, and thus does not require an "observer". It just needs the system to be a bit leaky.