Fundamental limits on constraining primordial non-Gaussianity

Theoretical Physic

The reconstructed CMB lensing bispectrum

Weak gravitational lensing by the intervening large-scale structure (LSS) of the Universe is the leading non-linear effect on the anisotropies of the cosmic microwave background (CMB). The integrated line-of-sight mass that causes the distortion -- known as lensing convergence -- can be reconstructed from the lensed temperature and polarization anisotropies via estimators quadratic in the CMB modes, and its power spectrum has been measured from multiple CMB experiments. Sourced by the non-linear evolution of structure, the bispectrum of the lensing convergence provides additional information on late-time cosmological evolution complementary to the power spectrum. However, when trying to estimate the summary statistics of the reconstructed lensing convergence, a number of noise-biases are introduced, as previous studies have shown for the power spectrum. Here, we explore for the first time the noise-biases in measuring the bispectrum of the reconstructed lensing convergence. We compute the leading noise-biases in the flat-sky limit and compare our analytical results against simulations, finding excellent agreement. Our results are critical for future attempts to reconstruct the lensing convergence bispectrum with real CMB data

Differences in the Motor Coordination Abilities among Adolescent Gymnasts, Swimmers, and Ice Hockey Players

© 2017 Human Movement. Purpose. Motor coordination is proposed to be a relatively stable age-related construct, unlikely to be influenced by aligned experiential factors such as intensive sport-specific training. The purpose of the study is to investigate if there are differences in motor coordination abilities among young artistic gymnasts, swimmers, and ice hockey players. Methods. The participants of the study were 508 female and 258 male adolescents (age, M = 12.80, SD = 1.10) comprising artistic gymnasts (n = 463), swimmers (n = 70), and ice hockey players (n = 233). The KTK-test protocol was used to analyse their gross motor coordination abilities. Results. The results of the study demonstrated that gymnasts scored better than ice hockey players and swimmers in the test of walking backwards along a beam, and better than ice hockey players in total motor coordination, hopping over an obstacle, and the test of moving sideways on wooden boards. However, ice hockey players scored higher than swimmers and gymnasts in the test of jumping from side to side. Subsequently, swimmers obtained better results in the test of moving sideways on wooden boards as compared with ice hockey players. Conclusions. The study results indicate that intensive sport-specific training may extend young athletes′ motor coordination characteristics in the ability areas representative of the sport in which they engage

Teacher perspectives on language learning psychology

Research into the psychology of language learning has grown exponentially in the last decade, yet, teacher perspectives on the field have been surprisingly absent from this body of research. The present study was designed to address this gap. Drawing on a survey with 311 foreign language teachers working at different school levels in 3 European countries, and on individual, semi-structured interviews with 11 teachers, the study focuses on the psychological aspects of language learning which teachers felt were particularly important in their own settings. In particular, teachers’ beliefs, experiences and teaching strategies were explored. The data also revealed strong interconnections between language learning psychology constructs, differences across contexts, and a perceived link between learner and teacher psychology