Local Correlations in the Super Tonks-Girardeau Gas

We study the local correlations in the super Tonks-Girardeau gas, a highly excited, strongly correlated state obtained in quasi one-dimensional Bose gases by tuning the scattering length to large negative values using a confinement-induced resonance. Exploiting a connection with a relativistic field theory, we obtain results for the two-body and three-body local correlators at zero and finite temperature. At zero temperature our result for the three-body correlator agrees with the extension of the results of Cheianov et al. [Phys. Rev. A 73, 051604(R) (2006)], obtained for the ground-state of the repulsive Lieb-Liniger gas, to the super Tonks-Girardeau state. At finite temperature we obtain that the three-body correlator has a weak dependence on the temperature up to the degeneracy temperature. We also find that for temperatures larger than the degeneracy temperature the values of the three-body correlator for the super Tonks-Girardeau gas and the corresponding repulsive Lieb-Liniger gas are rather similar even for relatively small couplings

Specific learning difficulties in second language learning and teaching

Individual differences that have an impact on the processes and outcomes of second language (L2) learning have been thoroughly investigated; but, until recently, the study of language learners with additional needs was at the periphery of both second language acquisition (SLA) and language teaching pedagogy (e.g. Nijakowska, 2010; Kormos & Smith, 2012; Kormos, 2017). Specific learning difficulties (SLDs), which affect between 5 and 15% of the population (Drabble, 2013), often have an impact on how additional languages are acquired. Therefore, in order to create an inclusive language learning context and set up effective instructional programmes, it is essential to understand how children with SLDs develop their competence in additional languages

Investigating Executive Working Memory and Phonological Short-Term Memory in Relation to Fluency and Self-Repair Behavior in L2 Speech

This paper reports the findings of a study investigating the relationship of executive working memory (WM) and phonological short-term memory (PSTM) to fluency and self-repair behavior during an unrehearsed oral task performed by second language (L2) speakers of English at two levels of proficiency, elementary and lower intermediate. Correlational analyses revealed a negative relationship between executive WM and number of pauses in the lower intermediate L2 speakers. However, no reliable association was found in our sample between executive WM or PSTM and self-repair behavior in terms of either frequency or type of self-repair. Taken together, our findings suggest that while executive WM may enhance performance at the conceptualization and formulation stages of the speech production process, self-repair behavior in L2 speakers may depend on factors other than working memory

On Form Factors in nested Bethe Ansatz systems

We investigate form factors of local operators in the multi-component Quantum Non-linear Schr\"odinger model, a prototype theory solvable by the so-called nested Bethe Ansatz. We determine the analytic properties of the infinite volume form factors using the coordinate Bethe Ansatz solution and we establish a connection with the finite volume matrix elements. In the two-component models we derive a set of recursion relations for the "magnonic form factors", which are the matrix elements on the nested Bethe Ansatz states. In certain simple cases (involving states with only one spin-impurity) we obtain explicit solutions for the recursion relations.Comment: 34 pages, v2 (minor modifications

The role of modality and awareness in language learning

There is conflicting empirical evidence regarding the role of awareness in second language learning. Possible explanations for the contradictory results include the modality in the exposure and assessment phases of previous experiments. Our study investigated the acquisition of a novel determiner system under incidental exposure conditions and examined the effect of modality in both exposure and assessment phases. Animacy served as a hidden regularity in the determiners, which were embedded in sentences and presented to Chinese speakers of English either in auditory or in visual mode. Learning was assessed by a two-alternative forced-choice test either auditorily or in writing. Implicit and explicit knowledge were measured using retrospective verbal reports and source judgements. Bayesian analysis provided moderate evidence for above chance level learning. Significant learning effects were observed regardless of whether participants based their accuracy judgements on explicit or implicit knowledge. Bayesian analysis showed moderate evidence for above chance learning effects for aware participants. Generalized linear mixed-effects modeling revealed a small-size significant benefit of the auditory exposure modality over the written modality but indicated no significant effect of the modality of assessment or awareness. Our research underscores the importance of considering the role of modality of exposure in incidental second language learning contexts