Holographic Nambu Jona-Lasinio Interactions

NJL interactions are introduced into the D3/ probe D7 system using Witten's double trace operator prescription which includes the operator as a classical term in the effective potential. In the supersymmetric system they do not induce chiral symmetry breaking which we attribute to the flat effective potential with quark mass in the supersymmetric theory. If additional supersymmetry breaking is introduced then standard NJL behaviour is realized. In examples where chiral symmetry breaking is not preferred such as with a B field plus an IR cut off chiral condensation is triggered by the NJL interaction at a second order transition after a finite critical coupling. If the model already contains chiral symmetry breaking, for example in the B field case with no IR cut off, then the NJL interaction enhances the quark mass at all values of the NJL coupling. We also consider the system at finite temperature: the temperature discourages condensation but when combined with a magnetic field we find regions of parameter space where the NJL interaction triggers a first order chiral transition above a critical coupling.Comment: 7 pages, 6 figure

Can paraphrasing increase the amount and accuracy of reports from child eyewitnesses?

Young children’s descriptions of sexual abuse are often sparse thus creating the need for techniques that elicit lengthier accounts. ‘Paraphrasing’, or repeating information children have just disclosed, is a technique sometimes used by forensic interviewers to clarify or elicit information. (e.g., if a child stated “He touched me”, an interviewer could respond “He touched you?”). However, the effects of paraphrasing have yet to be scientifically assessed. The impact of different paraphrasing styles on young children’s reports was investigated. Overall, paraphrasing per se did not improve the length, richness, or accuracy of reports when compared to open-ended prompts such as “tell me more,” but some styles of paraphrasing were more beneficial than others. The results provide clear recommendations for investigative interviewers about how to use paraphrasing appropriately, and which practices can compromise the quality of children’s reports

Binding an event to its source at encoding improves children\u27s source monitoring

Children learn information from a variety of sources and often remember the content but forget the source. While the majority of research has focused on retrieval mechanisms for such difficulties, the present investigation examines whether the way in which sources are encoded influences future source monitoring. In Study 1, 86 children aged 3 to 8 years participated in two photography sessions on different days. Children were randomly assigned to either the Difference condition (they were asked to pay attention to differences between the two events), the Memory control condition (asked to pay attention with no reference to differences), or the No-Instruction control (no special instructions were given). One week later, during a structured interview about the photography session, the 3-4 year-olds in the No-Instruction condition were less accurate and responded more often with \u27don\u27t know\u27 than the 7-8 year-olds. However, the older children in the Difference condition made more source confusions than the younger children suggesting improved memory for content but not source. In Study 2, the Difference condition was replaced by a Difference-Tag condition where details were pointed out along with their source (i.e., tagging source to content). Ninety-four children aged 3 to 8 years participated. Children in the Difference-Tag condition made fewer source-monitoring errors than children in the Control condition. The results of these two studies together suggest that binding processes at encoding can lead to better source discrimination of experienced events at retrieval and may underlie the rapid development of source monitoring in this age range

E, B, \mu, T Phase Structure of the D3/D7 Holographic Dual

The large N_c N=4 gauge theory with quenched N=2 quark matter displays chiral symmetry breaking in the presence of a magnetic field. We previously studied the temperature and chemical potential phase structure of this theory in the grand canonical ensemble - here we, in addition, include the effect of an electric field which acts to counter chiral symmetry breaking by disassociating mesons. We compute using the gravity dual based on the D3/probe-D7 brane system. The theory displays two transition at one of which chiral symmetry is restored. At the other transition density switches on, the mesons of the theory become unstable and a current forms, making it a conductor-insulator transition. Through the temperature, electric field, chemical potential volume (at fixed magnetic field parallel to the electric field) these transitions can coincide or separate at critical points, and be first order or second order. We map out this full phase structure which provides varied computable examples relevant to strongly coupled gauge theories and potentially condensed matter systems.Comment: 20 pages, 7 figure

Holography of the Conformal Window

Inspired by the model of Jarvinen and Kiritsis, we present a simple holographic model for the on set of chiral symmetry breaking at the edge of the conformal window in QCD in the Veneziano limit. Our most naive model enforces the QCD two loop running coupling on a D3/D7 holographic brane system. The mass of the holographic field, describing the chiral condensate in the model, is driven below the BF bound when the running is sufficiently strong, triggering chiral symmetry breaking for N_f/N_c<2.9. This model though contains too great a remnant of supersymmetry and does not correctly encode the perturbative anomalous dimensions of QCD. In a second model we impose the QCD anomalous dimension result and find chiral symmetry breaking sets in for N_f/N_c=4 at a BKT-type phase transition. In this case the transition is triggered when the anomalous dimension of the mass operator \gamma_m=1.Comment: 10 pages, 2 figures, v2: minor corrections, improved Figure

Equivalence of two approaches for the inhomogeneous density in the canonical ensemble

In this article we show that the inhomogeneous density obtained from a density-functional theory of classical fluids in the canonical ensemble (CE), recently presented by White et al [Phys. Rev. Lett. 84 (2000) 1220], is equivalent to first order to the result of the series expansion of the CE inhomogeneous density introduced by Gonzalez et al [Phys. Rev. Lett. 79 (1997) 2466].Comment: 6 pages, RevTe

The use of paraphrasing in investigative interviews

Objective Young children’s descriptions of maltreatment are often sparse thus creating the need for techniques that elicit lengthier accounts. One technique that can be used by interviewers in an attempt to increase children’s reports is ‘paraphrasing’, or repeating information children have disclosed. Although we currently have a general understanding of how paraphrasing may influence children’s reports, we do not have a clear description of how paraphrasing is actually used in the field. Method The present study assessed the use of paraphrasing in 125 interviews of children aged 4 to 16 years conducted by police officers and social workers. All interviewer prompts were coded into four different categories of paraphrasing. All children’s reports were coded for the number of details in response to each paraphrasing statement. Results ‘Expansion paraphrasing’ (e.g., “you said he hit you. Tell me more about when he hit you”) was used significantly more often and elicited significantly more details, while ‘yes/no paraphrasing’ (e.g., “he hit you?”) resulted in shorter descriptions from children, compared to other paraphrasing styles. Further, interviewers more often distorted children’s words when using yes/no paraphrasing, and children rarely corrected interviewers when they paraphrased inaccurately. Conclusions and Practical Implications Investigative interviewers in this sample frequently used paraphrasing with children of all ages and, though children’s responses differed following the various styles of paraphrasing, the effects did not differ by the age of the child witness. The results suggest that paraphrasing affects the quality of statements by child witnesses. Implications for investigative interviewers will be discussed and recommendations offered for easy ways to use paraphrasing to increase the descriptiveness of children’s reports of their experiences

D3-D5 Holography with Flux

It is shown that the Berezinski-Kosterlitz-Thouless phase transition that has been found in D3-D5 brane systems with nonzero magnetic field and charge density can also be found by tuning an extra-dimensional magnetic flux. We find numerical solutions for the probe D5-brane embedding and discuss properties of the solutions. We also demonstrate that the nontrivial embeddings include those which can be regarded as spontaneously breaking chiral symmetry