Quantum Mechanics and the Real World

Valia Allori, Detlef D uuml rr, Shelly Goldstein +1 more

Classical physics is about real objects, like apples falling from trees, whose motion is governed by Newtonian laws. In standard quantum mechanics only the wavefunctions or the results of measurements exist, and to answer the question of how the classical world can be part of the quantum world is a rather formidable task. However, this is not the case for Bohmian mechanics which, like classical mechanics, is a theory about real objects. In Bohmian terms, the problem of the classical limit becomes very simple: when do the Bohmian trajectories look Newtonian?

Cătălin Silviu Nuțu, Tiberiu Axinte

The paper is providing a different approach to real-world systems, such as micro and macro systems of our real life, where the man has little or no influence on the system, either not knowing the rules of the respective system or not knowing the input of the system, being thus mainly only spectator of the system’s output. In such a system, the input of the system and the laws ruling the system could be only “guessed”, based on intuition or previous knowledge of the analyzer of the respective system. But, as we will see in the paper, it exists also another, more theoretical and hence scientific way to approach the matter of the real-world systems, and this approach is mostly based on the theory related to Schrödinger’s equation and the wave function associated with it and quantum mechanics as well. The main results of the paper are regarding the utilization of the Schrödinger’s equation and related theory but also of the Quantum mechanics, in modeling real-life and real-world systems.

Bryce Seligman DeWitt

Peter J. Lewis

Abstract This chapter considers the worry that, rather than there being no description of the microworld available, there may be several competing descriptions. The problematic role of measurement in standard quantum mechanics is explained. Three leading approaches for responding to the measurement problem are laid out—spontaneous collapse theories, hidden variable theories, and many-worlds theories. This is a prima facie example of underdetermination: Several incompatible descriptions of the world are consistent with the phenomena. However, it has been argued that there is no real underdetermination here, because the former two approaches reduce to the many-worlds approach. This argument is shown to rest on unresolved questions concerning the empirical adequacy of the many-worlds approach. So at present the underdetermination remains, but it is argued that it presents no real barrier to deriving metaphysical conclusions from quantum mechanics.

O. Penrose