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تسجيل مستخدم جديدTime in Quantum Theory
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H. D. Zeh
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The concept of time as used in various applications and interpretations of quantum theory is briefly reviewed.
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Via the proper-time eigenstates (event states) instead of the proper-mass eigenstates (particle states), free-motion time-of-arrival theory for massive spin-1/2 particles is developed at the level of quantum field theory. The approach is based on a p
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The symmetry of quantum theory under time reversal has long been a subject of controversy because the transition probabilities given by Borns rule do not apply backward in time. Here, we resolve this problem within a rigorous operational probabilisti
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The standard formulation of quantum theory assumes a predefined notion of time. This is a major obstacle in the search for a quantum theory of gravity, where the causal structure of space-time is expected to be dynamical and fundamentally probabilist
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We apply the recently developed general theory of quantum time distributions arXiv:2010.07575 to find the distribution of arrival times at the detector. Even though the Hamiltonian in the absence of detector is hermitian, the time evolution of the sy
stem before detection involves dealing with a non-hermitian operator obtained from the projection of the hermitian Hamiltonian onto the region in front of the detector. Such a formalism eventually gives rise to a simple and physically sensible analytical expression for the arrival time distribution, for arbitrary wave packet moving in one spatial dimension with negligible distortion.
Quantum Theory, similar to Relativity Theory, requires a new concept of space-time, imposed by a universal constant. While velocity of light $c$ not being infinite calls for a redefinition of space-time on large and cosmological scales, quantization
of action in terms of a finite, i.e. non vanishing, universal constant $h$ requires a redefinition of space-time on very small scales. Most importantly, the classical notion of time, as one common continuous time variable and nature evolving continuously in time, has to be replaced by an infinite manifold of transition rates for discontinuous quantum transitions. The fundamental laws of quantum physics, commutation relations and quantum equations of motion, resulted from Max Borns recognition of the basic principle of quantum physics: {bf To each change in nature corresponds an integer number of quanta of action}. Action variables may only change by integer values of $h$, requiring all other physical quantities to change by discrete steps, quantum jumps. The mathematical implementation of this principle led to commutation relations and quantum equations of motion. The notion of point in space-time looses its physical significance; quantum uncertainties of time, position, just as any other physical quantity, are necessary consequences of quantization of action.
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