NCTS (South)


DATE2019-12-30

TIME12:10

PLACER49223, Second Physics Building , NCKU

FIELDQuantum Information Science

SPEAKER Prof. Shiang Yi Han(韓相宜) - 國立高雄大學應用物理學系

TITLE100 Years of Quantum Mechanics: Past, Present, and Future

ABSTRACTQuantum mechanics is the most precise description of the atomic world. However, its probability interpretation confuses physicists especially to those who believe that the causality dominants the entire universe. Some casual formulations of quantum mechanics arise with different perspectives such as the path integral, variational formulation, pilot-wave theory, and so on. Physicists dedicate to unifying classical mechanics and quantum mechanics for nearly 100 years even at the infancy of the quantum era. All speculations and deductions of deterministic quantum theories remain theoretical till the first observation of the average trajectories of single photons in a two-slit interferometer is achieved1. The weak measurement is applied to this experiment, which allows observable to lie outside the range of eigenvalues and may even be complex-valued2. The less constraint of the range can be regarded as the less influence caused by the measuring process, or maybe imply an existence of a complex space. In this talk, how a quantum particle move in a complex space under the optimal guidance law will be introduced 3. And how an ensemble of complex random trajectories of the quantum harmonic oscillator can interpret the correspondence principle in the classical and quantum mechanical limits will be demonstrated4. Some quantum phenomena and properties, including tunneling effect, zero-point energy, electron shell structure in hydrogen, and so on will be discussed. The potential extension future works will then be proposed, including the quantum control, quantum information, quantum cryptography. In particular, the prediction of the small perturbation of electron spin angular momentum is presented as the future experimental challenge. 1. S.Kocsis, B. Braverman, S. Ravets, and etal, Observing the average trajectories of single photons in a two-slit interferometer, Science 332, 1170-1173 (2011) 2. Y. Aharonov, D. Z. Albert, and L. Vaidman, How the result of measurement of a component of the spin of a spin-1/2 particle can turn out to be 100, Phys. Rev. Lett. 60, 1351-1354 (1993). 3. C. D. Yang, and L. L. Cheng, Optimal guidance law in quantum mechanics, Ann. of Phys, 338, 167-185 (2013). 4. C. D. Yang, and S. Y. Han, Trajectory interpretation of correspondence principle: solution of nodal issue, arXiv:1911.04747 (2019).