Black hole remnant in asymptotic Anti-de Sitter space

It is known that a solution of remnant were suggested for black hole ground state after surface gravity is corrected by loop quantum effect. On the other hand, a Schwarzschild black hole in asymptotic Anti-de Sitter space would tunnel into the thermal soliton solution known as the Hawking-Page phase transition. In this letter, we investigate the low temperature phase of three-dimensional BTZ black hole and four-dimensional AdS Schwarzschild black hole. We find that the thermal soliton is energetically favored than the remnant solution at low temperature in three dimensions, while Planck-size remnant is still possible in four dimensions. Though the BTZ remnant seems energetically disfavored, we argue that it is still possible to be found in the overcooled phase if strings were present and its implication is discussed.Comment: 13 pages, 5 figures, submitted versio

Holographic study on the jet quenching parameter in anisotropic systems

We first calculate the jet quenching parameter of an anisotropic plasma with a U(1) chemical potential via the AdS/CFT duality. The effects of charge, anisotropy parameter and quark motion direction on the jet quenching parameter are investigated. We then discuss the situation of anisotropic black brane in the IR region. We study both the jet quenching parameters along the longitudinal direction and transverse plane

Holographic QCD with Topologically Charged Domain-Wall/Membranes

We study the thermodynamical phase structures of holographic QCD with nontrivial topologically charged domain-wall/membranes which are originally related to the multiple $\theta$-vacua in the large $N_c$ limit. We realize the topologically charged membranes as the holographic D6-brane fluxes in the Sakai-Sugimoto model. The D6-brane fluxes couple to the probe D8-anti-D8 via Chern-Simon term, and act as the source for the baryonic current density of QCD. We find rich phase structures of the dual meson system by varying asymptotic separation of D8 and anti-D8. Especially, there can be a thermodynamically favored and stable phase of finite baryonic current density. This provides the supporting evidence for the discovery of the topologically charged membranes found in the lattice QCD calculations. We also find a crossover phase with the limiting baryonic current density and temperature which suggest a Hagedorn-like phase transition of meson dissociation.Comment: 23 pages, 19 figures;v2 typos corrected;v3 text improve

Mothers', preschool teachers', and speech-language pathologists' shared book reading with preschoolers in Taiwan

The purpose of this study was to explore mothers', preschool teachers', and speech-language pathologist's (SLP) shared book reading practices with preschoolers in Taiwan. Ten mothers, 10 preschool teachers, 10 SLPs and 30 preschoolers aged from 3 years 2 months old to 5 years 5 months old participated in this study. All participants were Taiwanese. Adults completed questionnaires about their shared book reading practices and participated in a shared book reading session with a preschool child using an unfamiliar book. The shared book reading between adult and child dyads were video and audio recorded. Mothers and preschool teachers read with typically developing children and SLPs read with children with specific language impairment. It was found that half of the mothers began to read to their children around one year of age. Most of the mothers read picture books with their child multiple times a week for 5 to 20 minutes in one book reading session. Also, mothers asked significantly more decontextualized questions than contextualized questions during shared book reading, with a large effect size. The mothers' level of education may be a factor associated with their greater use of decontextualized questions compared to contextualized questions. Most of the Taiwanese preschool teachers read with children multiple times a week for 10 to 20 minutes in one book reading session. The most often selected reading material was a picture book. There was no difference between the teachers' production of contextualized compared to decontexualized questions; however, a moderate effect size was present. The age of the child being read to and the level of teacher education may have affected the use of contextual questions, with more contextual questions being used with three year olds and by teachers with less education. A majority of the Taiwanese SLPs conducted shared book reading with children multiple times a week and each book reading session took 10 to 20 minutes for most of the SLPs. Picture books were most often selected by SLPs. No significant difference was present between SLPs' production of contextualized and decontextualized questions. However, a medium effect size was evident. Children's age might have influenced the SLPs' types of questions during shared book reading. SLPs tended to ask more contextualized questions than decontextualized questions when reading with 3 year olds compared to 4 and 5 year olds