67,342 research outputs found
An Exact Solution for Quantum Tunneling in a Dissipative System
Applying a technique developed recently [1,2] for an harmonic oscillator
coupled to a bath of harmonic oscillators, we present an exact solution for the
tunneling problem in an Ohmic dissipative system with inverted harmonic
potential. The result shows that while the dissipation tends to suppress the
tunneling, the Brownian motion tends to enhance the tunneling. Whether the
tunneling rate increases or not would then depend on the initial conditions. We
give a specific formula to calculate the tunneling probability determined by
various parameters and the initial conditions.Comment: The reference 2 is changed to Phys. Lett. from Phys. Rev. Let
Voices from the diaspora: changing hierarchies and dynamics of Chinese multilingualism
The so-called Chinese diasporas, i.e. Chinese communities outside Greater China (China, Hong Kong, Macau, and Taiwan), have traditionally been dialect dominant; that is, the vast majority of Chinese immigrants are speakers of (especially Southern) dialects. Cantonese and Hokkien are two of the most prominent dialects. With globalization and the rise of China as a world politico-economic power, the national, standardized variety, Putonghua, is gaining particular prestige amongst the Chinese diasporas. For example, all the Cantonese schools for British Chinese children in the UK now also teach Putonghua, but none of the Putonghua schools teach Cantonese. Using ethnographic interviews with and participant observation of Chinese people of different generations in various diasporic communities, this paper examines the changing hierarchies of varieties of Chinese, the implications of such changes for the education and identity development of the young, and the constitution of a (speech) community in the post-modern era. It focuses on language attitude and linguistic practices (including literacy practices). It also investigates the tensions between the competing ideologies and discourses on national and ethnic identities, nationalism, community relations and cultural values
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