| Causality |
|
| The real problem | |
|
Page 1 of 2 Because quantum-mechanical probabilities are assigned on the supposition that there is an outcome (or, what comes to the same, on the supposition that the probabilities of the possible outcomes of a measurement add up to 1), value-indicating events (such as the transition of a pointer from its neutral to a value-indicating position) lack causally sufficient conditions. Such events are unpredictable not in the "anemic" sense associated with the chaotic regime of a deterministic system, for there is no such thing as a deterministic system, nor are they unpredictable merely in the trivial sense that the outcome of a successful measurement cannot be predicted in general. Value-indicating events are unpredictable also in the sense that it is impossible to predict their occurrence. It is therefore beyond the scope of the quantum theory to provide sufficient conditions for the occurrence of a value-indicating event. If quantum theory is indeed the fundamental theoretical framework of physics — and neither are there empirical reasons to doubt it nor does anyone have the faintest ideas what could replace it — this means that value-indicating events are uncaused.
Transport VI by Eric J. Heller. The Transport series renders electron flow paths in a 'two dimensional electron gas'. Transport VI is based on the actual electron flow patterns for electrons riding over a bumpy landscape.
Differently put, since the quantum formalism is but a set of tools for calculating correlations between measurement outcomes — diachronic corrrelations between outcomes of measurements performed on the same system at differtent times as well as synchronic correlations between outcomes of measurements performed on different systems in spacelike relation — it presupposes the occurrence of measurement outcomes, and therefore it cannot account for them. By no means is this a shortcoming of the theory or any particular interpretation of the theory. It is the sober recognition of the impossibility of explaining why there is anything, rather than nothing at all. Every physical theory defines a set of nomologically possible worlds. No physical theory can tell us why, among all nomologically possible worlds, there is an actual world, or why the actual world is this rather than another nomologically possible world. In a classical many-body context, we identify the actual world by specifying a complete set of initial positions and momenta, or by specifying a complete set of final positions and momenta, or by specifying a complete set of initial and final positions. In quantum mechanics we identify the actual world by specifying all value-indicating events, along with the indicated values. Another point to be emphasized in this context is that no fundamental theory can be explained the way Kepler's laws of planetary motion can be explained, on the basis of a "more fundamental" theory — in this case Newton's law of gravity — inasmuch as "fundamental" lacks a comparative. (If there is a "more fundamental" theory, the "less fundamental" theory isn't fundamental at all.)
Moreover, the classical sleight-of-hand, which consisted in the transmogrification of a mathematical algorithm into a physical mechanism or process, no longer works. |
|
| < Prev | Next > |
|---|
