Investigating tip-of-the-tongue states in Norwegian-English bilinguals : Effects of word frequency, cognate status and noun type in word retrieval, in relation to the bilingual profile

Master´s thesis in English (EN501)The current study aimed to explore the effects of frequency, cognate status and noun type in tip-of-the-tongue occurrences in Norwegian-English bilinguals. In what manner the bilingual profile may exert influence on the matter was of additional interest. This study also attempted to relate results to the varying approaches presented by the weaker links hypothesis and the competition hypothesis. Stimuli sets were created consisting of target words controlled for the aforementioned manipulations and randomly dispersed throughout experiment blocks. Predictions were made based on language production models and results from similar studies performed previously. Upon completing bilingual profile questionnaires (LEAP-Q), participants were tested by being given definitions aiming to induce TOTs in both languages. In order to investigate the effect of difference in language profile on our findings, the results from the LEAP-Q factor analysis were included in the mixed effects model. Correctly predicted was that participants experienced greater TOT occurrences in their non-dominant language and showed higher TOT rates for low-frequency words. Participants of lower proficiency produced more TOTs, showing English proficiency to be the only factor to predict TOTs. Controversially, results showed that more TOTs were experienced for cognate words, specifically proper nouns. Future studies are required to further dissect the underlying retrieval processes pertaining to the tip-of-the-tongue states in bilinguals

Representation of the virtual space in extended systems – a correlation energy convergence study

We present an investigation of the convergence behaviour of the local second-order Møller-Plesset perturbation theory (MP2) correlation energy toward the canonical result for three insulating crystals with either projected atomic orbitals (PAOs) or various orthonormal representations of the virtual orbital space. Echoing recent results for finite molecular systems, we find that significantly fewer PAOs than localised orthonormal virtual orbitals are required to reproduce the canonical correlation energy. We find no clear-cut correlation between conventional measures of orbital locality and the ability of the representation to span the excitation space of local domains. We show that the PAOs of the reference unit cell span parts of the excitation space that can only be reached with distant local orthonormal virtual orbitals

An optimized chiral nucleon-nucleon interaction at next-to-next-to-leading order

We optimize the nucleon-nucleon interaction from chiral effective field theory at next-to-next- to-leading order. The resulting new chiral force NNLOopt yields \chi^2 \approx 1 per degree of freedom for laboratory energies below approximately 125 MeV. In the A = 3, 4 nucleon systems, the contributions of three-nucleon forces are smaller than for previous parametrizations of chiral interactions. We use NNLOopt to study properties of key nuclei and neutron matter, and demonstrate that many aspects of nuclear structure can be understood in terms of this nucleon-nucleon interaction, without explicitly invoking three-nucleon forces.Comment: 6 pages, 4 figure

Computational Nuclear Physics and Post Hartree-Fock Methods

We present a computational approach to infinite nuclear matter employing Hartree-Fock theory, many-body perturbation theory and coupled cluster theory. These lectures are closely linked with those of chapters 9, 10 and 11 and serve as input for the correlation functions employed in Monte Carlo calculations in chapter 9, the in-medium similarity renormalization group theory of dense fermionic systems of chapter 10 and the Green's function approach in chapter 11. We provide extensive code examples and benchmark calculations, allowing thereby an eventual reader to start writing her/his own codes. We start with an object-oriented serial code and end with discussions on strategies for porting the code to present and planned high-performance computing facilities.Comment: 82 pages, to appear in Lecture Notes in Physics (Springer), "An advanced course in computational nuclear physics: Bridging the scales from quarks to neutron stars", M. Hjorth-Jensen, M. P. Lombardo, U. van Kolck, Editor

Investigating tip-of-the-tongue states in Norwegian-English bilinguals : Effects of word frequency, cognate status and noun type in word retrieval, in relation to the bilingual profile

The current study aimed to explore the effects of frequency, cognate status and noun type in tip-of-the-tongue occurrences in Norwegian-English bilinguals. In what manner the bilingual profile may exert influence on the matter was of additional interest. This study also attempted to relate results to the varying approaches presented by the weaker links hypothesis and the competition hypothesis. Stimuli sets were created consisting of target words controlled for the aforementioned manipulations and randomly dispersed throughout experiment blocks. Predictions were made based on language production models and results from similar studies performed previously. Upon completing bilingual profile questionnaires (LEAP-Q), participants were tested by being given definitions aiming to induce TOTs in both languages. In order to investigate the effect of difference in language profile on our findings, the results from the LEAP-Q factor analysis were included in the mixed effects model. Correctly predicted was that participants experienced greater TOT occurrences in their non-dominant language and showed higher TOT rates for low-frequency words. Participants of lower proficiency produced more TOTs, showing English proficiency to be the only factor to predict TOTs. Controversially, results showed that more TOTs were experienced for cognate words, specifically proper nouns. Future studies are required to further dissect the underlying retrieval processes pertaining to the tip-of-the-tongue states in bilinguals