Real Time Analysis of Thermal Activation via Sphaleron Transitions

We study the process of thermal activation mediated by sphaleron transitions by analyzing the real-time dynamics of the decay out of equilibrium in a $1+1$ dimensional field theory with a metastable state. The situation considered is that of a rapid supercooling in which the system is trapped in a metastable state at a temperature larger than the mass of the quanta, but smaller than the energy to create a critical droplet. The initial density matrix is evolved in time and the nucleation rate (probability current at the saddle point) is computed. The nucleation rate is {\it time dependent}, vanishing at early times, reaching a maximum at a time $t \approx 1/m$ with $m$ the mass of quanta in the metastable state, and decreasing at long times as a consequence of unitarity. An estimate for the average number of particles of ``true vacuum'' produced as a function of time during the nucleation process is obtained.Comment: 26 pages 6 figures (available upon request), PITT-93-06, LATE

Expatriation in Chinese MNEs in Africa: an agenda for research

Despite increasing Chinese MNE activity in emerging countries, there is a paucity of studies and critical analysis of expatriate management in Emerging Market Multinational Enterprises (EMMNEs).This article provides a needed critical evaluation of the literature and research, and identifies an agenda for research. Chinese firms’ expatriation policies and practices should be viewed differently to those of Western firms. This has implications for policy regarding state MNEs in African countries, and individual Chinese MNE expatriation policies. There are potential synergies between Chinese and African cultural values, moderated by a low importance of the knowledge transfer role of Chinese expatriates. This may be moderated by the relational nature of career development including expatriate selection and a low emphasis on pre-departure training. The main contribution of this work is to inform empirical research at organizational level by making explicit differences in Chinese MNE engagement in Africa to Western MNEs, how this may influence differences in expatriate policy and practices, and why this may contribute a different perspective to the extant expatriation literature