Baryogenesis from dark matter

We consider the possibility that some primordial fields decay purely into the dark sector creating asymmetric dark matter. This asymmetry is subsequently transmuted into leptons and baryons. Within this paradigm we compute the amount of asymmetric dark matter created from the out of equilibrium decays of the primordial fields with CP violating Yukawa couplings. The dark matter asymmetry is then transferred to the visible sector by the asymmetry transfer equation and generates an excess of $B-L$. Baryogenesis occurs via sphaleron processes which conserve $B-L$ but violate $B+L$. A mechanism for the annihilation of the symmetric component of dark matter is also discussed. The model leads to multi-component dark matter consisting of both bosonic and fermionic components.Comment: 6 pages, 1 figur

Massive Supermultiplets in Four-Dimensional Superstring Theory

We extend the discussion of arXiv:1007.5254 on massive Regge excitations on the first mass level of four-dimensional superstring theory. For the lightest massive modes of the open string sector, universal supermultiplets common to all four-dimensional compactifications with N = 1, 2 and N = 4 spacetime supersymmetry are constructed respectively -- both their vertex operators and their supersymmetry variations. Massive spinor helicity methods shed light on the interplay between individual polarization states.Comment: 75 pages, 13 figure

Stringy explanation of b→sℓ+ℓ−b \to s \ell^+ \ell^- anomalies

We show that the recent anomalies in $b \to s \ell^+ \ell^-$ transitions observed by the LHCb collaboration can be accommodated within string motivated models with a low mass $Z^{\prime}$ gauge boson. Such $Z^{\prime}$ gauge boson can be obtained in compactifications with a low string scale. We consider a class of intersecting D-brane models, in which different families of quarks and leptons are simultaneously realized at different D-brane intersections. The explanation of $b \to s \ell^+ \ell^-$ anomalies via a stringy $Z^{\prime}$ sets important restrictions on these viable D-brane constructions.Comment: 18 pages, 13 figure

Enabling Potential Disruptive Innovation by Customer-Orientated Processes: The Case of Chinese Firms

The growing recognition of disruptive innovation as an important phenomenon in competitive strategy has led researchers to examine the question of how to promote disruptive innovation. The extant literature has studied on the organisational preconditions for disruptive innovation to arise, including resource allocation processes, organisational structure, organisational culture, and R&D and production processes. Much less attention has been paid to the role of customer-oriented processes in enabling disruptive innovation. In this research we develop propositions about how customer-oriented processes can foster disruptive innovation by using a set of case studies of Chinese firms. These findings have important implications for firms wishing to fuel disruptive innovations

Nonlinear Negative Refraction by Difference Frequency Generation

Negative refraction has attracted much interest for its promising capability in imaging applications. Such an effect can be implemented by negative index meta-materials, however, which are usually accompanied by high loss and demanding fabrication processes. Recently, alternative nonlinear approaches like phase conjugation and four wave mixing have shown advantages of low-loss and easy-to-implement, but associated problems like narrow accepting angles can still halt their practical applications. Here we demonstrate theoretically and experimentally a new scheme to realize negative refraction by nonlinear difference frequency generation with wide tunability, where a thin BBO slice serves as a negative refraction layer bending the input signal beam to the idler beam at a negative angle. Furthermore, we realize optical focusing effect using such nonlinear negative refraction, which may enable many potential applications in imaging science

The Dynamic of Assets and Liabilities of Foreignness

Researchers have recognized that foreign firms possess both advantages and costs in operating in host countries. The extant literature suggests that the liability of foreignness can be gradually overcome as a foreign subsidiary learns more about the host country environment and develops better connections to local business networks. Based on a longitudinal case study of the Chinese management software industry, however, we find that even over the long term foreign firms continue to face difficulties in accessing some important potential country-specific advantages to overcome liability of foreignness. We develop a framework to explain why and how local firms more successfully access country-specific advantages at home because of their local complementary knowledge, local relationships, and home-focused strategies and understand the dynamic of assets and liability of foreignness. These findings have important implications for the persistence of liability of foreignness and for established MNEs wishing to compete in emerging markets as well as helping to explain the emergence of strong competition from local firms in emerging economies