Dark Light Higgs

We study a limit of the nearly-Peccei-Quinn-symmetric Next-to-Minimal Supersymmetric Standard Model possessing novel Higgs and dark matter (DM) properties. In this scenario, there naturally co-exist three light singlet-like particles: a scalar, a pseudoscalar, and a singlino-like DM candidate, all with masses of order 0.1-10 GeV. The decay of a Standard Model-like Higgs boson to pairs of the light scalars or pseudoscalars is generically suppressed, avoiding constraints from collider searches for these channels. For a certain parameter window annihilation into the light pseudoscalar and exchange of the light scalar with nucleons allow the singlino to achieve the correct relic density and a large direct detection cross section consistent with the CoGeNT and DAMA/LIBRA preferred region simultaneously. This parameter space is consistent with experimental constraints from LEP, the Tevatron, and Upsilon- and flavor physics.Comment: 4 pages, 4 figures, final version for Phys. Rev. Let

Entanglement Entropy in Timelike Slices: a Free Fermion Study

We define the entanglement entropy of a quantum state in a discrete set of points in an arbitrary spacetime slice, and give the explicit formula for free fermions. We investigate timelike (causal) slices specifically. For 1D lattice free fermions, we calculated the time-direction entanglement entropy in a set of times $t_n=n\tau$ ($1\le n\le K$) on the same site, and identified a stabilizing transition at $\tau=\tau_0=2\pi/E_0$, where $E_0$ is the energy range of single-fermion spectrum. At zero temperature, the time-like entanglement entropy of the lattice fermion with $\tau<\tau_0$ resembles the Cardy formula for one flavor of chiral fermion. For generic slices, the entanglement entropy shows a clear transition between spacelike and timelike slices. We conjecture $\tau_0$ is the upper bound of time period for consecutive local observations to retrieve information from a quantum state, and conjecture a similar $\tau_0$ exists in interacting models

Understanding the Barrier of Elder’s Adoption of B2C Online Commerce: Comparison Between Different Product Types and Ages

With the coming of aging society, the market for elderly people will become more and more important. The elder will become an important potential market for business. Therefore, understand elder’s adoption of online commerce is becoming a critical issue in MIS field. The purpose of this study is attempted to understand the barrier of elder’s adoption of B2C online commerce. Additionally, we compared the results across different product types and ages. Survey study was employed in this study. The main result discovered that the barriers affecting user adoption of B2C online commerce would differ with the variation of age range and product type. For the elder, risk barrier and image barrier dominate the decisions for tangible products, while value barrier and risk barrier dominate for the intangible products. This research result can become a practical reference. For both academic and business, this study has a certain contribution in the development of electronic commerce

Talent Demand and Urban Development in City A

The introduction of talent programs is one of the key programs in many cities in recent years. In order to “encourage and enrich the people and innovate the city”, cities such as Beijing, Shanghai, Wuhan, Chengdu, Xi’an and Shenzhen are using various attractive policies to compete for talents. Based on this, this paper uses BP neural network and analytic hierarchy process to model and analyze the talent demand of A-City and the development of the city.

Time dependent lyotropic chromonic textures in PDMS-based microfluidic confinements

Nematic and columnar phases of lyotropic chromonic liquid crystals (LCLCs) have been long studied for their fundamental and applied prospects in material science and medical diagnostics. LCLC phases represent different self-assembled states of disc-shaped molecules, held together by noncovalent interactions that lead to highly sensitive concentration and temperature dependent properties. Yet, microscale insights into confined LCLCs, specifically in the context of confinement geometry and surface properties, are lacking. Here, we report the emergence of time dependent textures in static disodium chromoglycate (DSCG) solutions, confined in PDMS-based microfluidic devices. We use a combination of soft lithography, surface characterization and polarized optical imaging to generate and analyze the confinement-induced LCLC textures, and demonstrate that over time, herringbone and spherulite textures emerge due to spontaneous nematic (N) to columnar M-phase transition, propagating from the LCLC-PDMS interface into the LCLC bulk. By varying the confinement geometry, anchoring conditions and the initial DSCG concentration, we can systematically tune the temporal dynamics of the N to M-phase transition and textural behaviour of the confined LCLC. Since static molecular states register the initial conditions for LC flows, the time dependent boundary and bulk conditions reported here suggest that the local surface-mediated dynamics could be central in understanding LCLC flows, and in turn, the associated transport properties of this versatile material