If anything, it tacitly suggests such pre-existence of a well-defined p since, after all, one could have chosen to measure it first instead of x. In particular, it does not say whether there actually was any pre-existing value of p to be disturbed in the first place. This widespread explanation, which perfectly abides by the orthodoxy of the Copenhagen interpretation, unfortunately obscures a more fundamental question. All too often, it is explained away by invoking a (presumed) disturbance caused by the measurement process whereby, say, the retrieval of x collapses the wave function, and therefore irrevocably corrupts any pre-existing information that it could have contained about p. However, physically-or rather, ontologically-the uncertainty principle is much more perplexing. The more one variable is well-defined, the more is its transform spread out, and hence ill-defined, in the conjugate domain. Mathematically, the principle is rather straightforward to explain, particularly in the wave function representation, where complementary variables can be visualized as Fourier transforms of one another. One learns, for instance, that a particle's position cannot be measured together with its momentum. One of the very first principles taught in undergraduate quantum mechanics is the uncertainty principle.
0 kommentar(er)
