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Shizhong Mei

Publications and source records attributed to Shizhong Mei.

3 recordsLinked to original sources

A general theory of quantum measurements

A universal energy eigenvalue equation is proposed in this paper. It is proven that the unique set of eigenfunctions or preferred basis exists for any non-isolated sub-system. Applying the new eigenvalue equation to the relative motion of a hydrogen atom together with the derived relativistic Hamiltonian to quantify the impact of finite proton mass to the fine structure, correction to the fine structure is obtained as a result of the entanglement of the relative motion and the center-of-mass motion, which can be used to verify the correctness of the proposed eigenvalue equation. Applying the equation to the measurement of electron double-slit interference, it is analyzed that the photon packets with Lorentzian spectral lineshape, the domain and state density of the sub-system, and the energy of the incident electron together determines the spontaneous emission rate of the incident electron. Photons generated in this process excite electrons from the valence band to the conduction band of the detector. Corresponding to any emitted or absorbed photon, the sub-system is found to be uniquely determined by maximizing the transition rate. This new principle is valid for atoms too. Closed-form expressions are obtained for the transition rates and example numerical results show good correlation between calculation and the position measurement experiment. The discovered common mechanisms that determine the sub-systems, the preferred bases, and transition rates form the foundation of a new, general, and consistent theory of quantum measurement.

quant-ph

On the origin of preferred-basis and evolution pattern of wave function

The standard quantum mechanics assumes Schrödinger equation for regular evolution and wave function collapse for measurement. As shown in this paper, only particular collapse equation can continuously transition to Schrödinge equation. The collapse equation also adds some restriction to the preferred-basis. Under the assumptions that the preferred-basis depends on the whole system Hamiltonian but is not affected by the weights of the basis functions in the system wave function, a unique set of determination equations of the basis functions is derived from the collapse equation. The second order time derivative of the wave function is continuous at the end of the collapse. To make the derivative continuous at the beginning of the collapse, it is proved that the collapse equation has to contain a cyclic function with period twice the duration of the collapse, which leads to conditioned alternating Schrödinger evolution and collapse of equal duration.

quant-ph

To Explain Results of Position Measurement by Self-Induced Photon Emission and Absorption

It is proposed in this paper that without a measurement, the wave function of a system periodically transits to a bound energy eigenfunction or the complementary wave function that is orthogonal to all the bound energy eigenfunctions. Applying this assumption to analyze results of position measurement shows that when the wave function of the entangled incident object and a position detector is a linear combination of the bound energy eigenfunctions of the entangled system prior to collapses, the detection rate essentially equals the probability flux of the incident object entering the detector. When the wave function of the entangled incident object and a position detector is not a linear combination of the bound energy eigenfunctions of the entangled system, results of position measurement can also be explained by the proposed self-induced photon emission and absorption.

quant-ph