On the measurement problem, decoherence and the language of
Quantum Mechanics
ABSTRACT: We discuss in this talk the measurement problem in Quantum
Mechanics, and the question of whether or not decoherence provides a
solution to it. We point out that Quantum Mechanics is best understood
in a weakly objective language rather than in a strongly objective
realist one where things are described as they "really" are,
independently of observations. We show that arguments referring to
decoherence are of no help if it is insisted that nature must be
described in terms of a strongly objective description. Decoherence,
however, does provide an answer to the measurement problem if such an
insistence is dropped. We also examine the envariance formalism of
Zurek which derives the Born rule without the use of the density
operator, avoiding any circularity. We argue that in this case too,
only a weakly objective description can be given. Finally, we briefly
comment on some of the recent attempts within quantum cosmology that
attempt to provide a strongly objective description of decoherence.
