Quantum mechanics permits nonlocality—both nonlocal correlations and nonlocal equations of motion—while respecting relativistic causality. Is quantum mechanics the unique theory that reconciles nonlocality and causality? We consider two models, going beyond quantum mechanics, of nonlocality: “superquantum” correlations, and nonlocal “jamming” of correlations. These models are consistent with so...

I am concerned with two views of quantum mechanics that John S. Bell called " unromantic " : spontaneous wave function collapse and Bohmian mechanics. I discuss some of their merits and report about recent progress concerning extensions to quantum field theory and relativity. In the last section, I speculate about an extension of Bohmian mechanics to quantum gravity.

In one-dimensional quantum mechanics, or the Sturm-Liouville theory, Crum’s theorem describes the relationship between the original and the associated Hamiltonian systems, which are iso-spectral except for the lowest energy state. Its counterpart in ‘discrete’ quantum mechanics is formulated algebraically, elucidating the basic structure of the discrete quantum mechanics, whose Schrödinger equa...

Quantum mechanics permits nonlocality—both nonlocal correlations and nonlocal equations of motion—while respecting relativistic causality. Is quantum mechanics the unique theory that reconciles nonlocality and causality? We consider two models, going beyond quantum mechanics, of nonlocality: “superquantum” correlations, and nonlocal “jamming” of correlations. These models are consistent with so...

[This paper is part of the Focused Collection on Upper Division Physics Courses.] Compared with introductory physics, relatively little is known about the development of expertise in advanced physics courses, especially in the case of quantum mechanics. Here, we describe a framework for understanding the patterns of student reasoning difficulties and how students develop expertise in quantum me...

Arguments have been raised that the system{observer cut of quantum mechanics can be shifted arbitrarily close to, or even into, the conscious observer. Here I show that this view leads to observable contradictions (despite our inability to control the phases of macroscopic states). For this purpose I modify and extend Schrr odinger's well{known superposition of a cat in its dead and alive state...

The measurement process for hidden–configuration formulations of quantum mechanics is analysed. It is shown how a satisfactory description of quantum measurement can be given in this framework. The unified treatment of hidden–configuration theories, including Bohmian mechanics and Nelson’s stochastic mechanics, helps in understanding the true reasons why the problem of quantum measurement can s...

Using classical statistics, Schrödinger equation in quantum mechanics is derived from complex space model[4]. Phase-space probability amplitude, that can be defined on classical point of view, has connections to probability amplitude in internal space and to wave function in quantum mechanics. In addition, the physical entity of wave function in quantum mechanics is confirmed once again.

The measurement process for hidden–configuration formulations of quantum mechanics is analysed. It is shown how a satisfactory description of quantum measurement can be given in this framework. The unified treatment of hidden–configuration theories, including Bohmian mechanics and Nelson’s stochastic mechanics, helps in understanding the true reasons why the problem of quantum measurement can s...