Naturalness and the muon magnetic moment

We study a predictive model for explaining the apparent deviation of the muon anomalous magnetic moment from the Standard Model expectation. There are no new scalars and hence no new hierarchy puzzles beyond those associated with the Higgs; the only new particles at the TeV scale are vector-like singlet and doublet leptons. Interestingly, this simple model provides a calculable example violating the Wilsonian notion of naturalness: despite the absence of any symmetries prohibiting its generation, the coefficient of the naively leading dimension-six operator for (g − 2) vanishes at one-loop. While effective field theorists interpret this either as a surprising UV cancellation of power divergences, or as a delicate cancellation between matching UV and calculable IR corrections to (g − 2) from parametrically separated scales, there is a simple explanation in the full theory: the loop integrand is a total derivative of a function vanishing in both the deep UV and IR. The leading contribution to (g − 2) arises from dimension-eight operators, and thus the required masses of new fermions are lower than naively expected, with a sizeable portion of parameter space already covered by direct searches at the LHC. The viable parameter space free of fine-tuning for the muon mass will be fully covered by future direct LHC searches, and all of the parameter space can be probed by precision measurements at planned future lepton colliders.

Technical artifact drives apparent deviation from Hardy-Weinberg equilibrium at CCR5-∆32 and other variants in gnomAD

Following an earlier report suggesting increased mortality due to homozygosity at the CCR5-∆32 allele1, Wei and Nielsen recently suggested a deviation from Hardy-Weinberg Equilibrium (HWE) observed in public variant databases as additional supporting evidence for this hypothesis2. Here, we present a re-analysis of the primary data underlying this variant database and identify a pervasive genotyping artifact, especially present at long insertion and deletion polymorphisms. Specifically, very low levels of contamination can affect the variant calling likelihood models, leading to the misidentification of homozygous individuals as heterozygous, and thereby creating an apparent depletion of homozygous calls, which is especially prominent at large insertions and deletions. The deviation from HWE observed at CCR5-∆32 is a consequence of this specific genotyping error mode rather than a signature of selective pressure at this locus.

Tactile distance illusions reflect a coherent stretch of tactile space

Illusions of the perception of distance between two touches on the skin have been described since the classic work of Weber in the 19th century. The perceptual mechanisms underlying such spatial distortions, however, remain poorly understood. One potential interpretation is that the representational space of touch is related to the true structure of the skin by a geometrically simple stretch. If distortions of tactile distance perception reflect a simple stretch of tactile space, perceived distance should vary predictably as a function of the orientation of the stimulus on the skin, showing a sinusoidal pattern. Here, we tested this prediction by obtained judgments of perceived tactile distance for pairs of touches aligned with eight orientations on the skin. Across four experiments, the results were highly consistent with this prediction, showing no apparent deviation from a model of simple stretch of tactile space. Similar results were apparent on both the dorsum and palm of the hand, as well as the forehead. These results show that spatial distortions of touch are well characterized by a geometrically simple stretch of tactile space.

EFFECTS OF ELECTRODE RESISTANCE ON THE DIELECTRIC BEHAVIORS OF Au/BaxSr1−xTiO3/La1.1Sr0.9NiO4 CAPACITORS

BaxSr[Formula: see text]TiO3 ([Formula: see text]) (BST) thin films were prepared on La[Formula: see text]Sr[Formula: see text]NiO4 (LSNO)/SrTiO3 (STO) structure by combinatorial pulsed laser deposition (comb-PLD). The capacitances of the Au/BST/LSNO capacitors exhibited strong frequency dependence especially when the applied frequency was higher than 10[Formula: see text]kHz. On the basis of an equivalent circuit model, we presented a theoretical simulation of the relationships between capacitance and frequency for the capacitors with different electrode serial resistances. Based on the fitting results, the observed strong frequency dependence of the measured capacitance at high frequency in our study could be ascribed to the large serial resistance of 750 [Formula: see text] for oxide electrode LSNO. Further simulation studies found that large serial resistance (1000 [Formula: see text]) could result in an apparent deviation from the intrinsic dielectric properties especially at high frequencies ([Formula: see text]100[Formula: see text]kHz) for capacitors with capacitances above 1[Formula: see text]nF. Our results provide useful information for the design of all-oxide electronic devices.

Ecological speciation! Or the lack thereof?This Perspective is based on the author’s J.C. Stevenson Memorial Lecture delivered at the Canadian Conference for Fisheries Research in Halifax, Nova Scotia, January 2008.

Ecological speciation occurs when adaptation to different environments or resources causes the evolution of reproductive isolation. This process is now thought to be very important in the evolution of biological diversity. Indeed, support for ecological speciation is so often asserted in the literature that one can get the impression of ubiquity. Eager to ride on the coattails of this exciting work, my own research has investigated ecological speciation in guppies, sticklebacks, and Darwin’s finches. Much to my initial dismay, I failed to find simple and strong signatures of ecological speciation in the first two of these systems. Setting aside the possibility of personal incompetence, my apparent deviation from ubiquity might simply reflect an existing literature bias. This bias seems obvious in retrospect given that essentially all published studies of ecological speciation purport to be confirmatory, whereas many cases of divergent selection and adaptive divergence are associated with only weak to modest levels of reproductive isolation. In short, different populations can be arrayed along a continuum from panmixia to complete reproductive isolation. Variation along this continuum might profitably be used for studying factors, outlined herein, that can promote or constrain “progress” toward ecological speciation.

Fundamental Plane and Merger Scenario

The Fundamental Plane (FP) is one of the most important universal relations in early type galaxies because it contains valuable information about the formative and evolutionary process of galaxies (Djorgovski & Davis 1987, Dressler et al. 1987). The commonly used form of the scaling relation in the FP is described as Re = σAIB, where Re, σ, and I are effective radius, central velocity dispersion, and mean surface brightness of elliptical galaxies, respectively. The exponents A, B are considered to be 1.56 ± 0.07 and −0.94 ± 0.09 in the FP derived by K band photometry, respectively, and these values deviate significantly from the values A = 2.0 and B = −1.0 expected from virial theorem (Pahre et al. 1995; Djorgovski, Pahre, & de Carvalho 1996). This apparent deviation requires that the ratio of dynamical mass (M) to luminosity of elliptical galaxies (L) depends on M as M/L ∝ Mα (α = 0.12 ± 0.03 for K band). Possible interpretations for the required dependence of M/L on M are generally considered to be divided into the following two. One is that the required dependence of M/L on M results from the fact that the mean stellar age and metalicity of elliptical galaxies depend systematically on M. The other is that the required dependence reflects the M dependence of structural and kinematical properties of elliptical galaxies (“nonhomology”). Although we should not neglect the importance of stellar populations in generating the M dependence of the M/L (Renzini & Ciotti 1993), we here consider that the origin of the required M dependence of M/L is closely associated with the structural and kinematical properties dependent on M or L in elliptical galaxies.

The Functions of the Conjugations in Colloquial israeli Hebrew

The main purpose of this article is to show that the conjugations (binyanim) in Colloquial Israeli Hebrew, looked at from the point of view of their syntactic and semantic functions, form together a coherent, tightly organized system, in which each conjugation is characterized by a fixed configuration of semantic and syntactic properties. These properties are represented in terms of three concepts, defined and explained in §4: semantic value, semantic tie-up, and syntactic tie-up. There are many deviations from the regular pattern of the system, but relatively few of these are true exceptions. In the majority of cases either there is a rule which explains the apparent deviation, or the deviation should be considered unimportant in some definite sense.

POLARIZATION OF ELASTICALLY SCATTERED 1.33-MeV PHOTONS

Measurements have been made as a function of angle of the polarization of 1.33-MeV gamma rays elastically scattered by lead. The analysis of the experimental data included the contribution of the L-shell electrons to inelastic Compton scattering. The results show no apparent deviation from the polarizations expected on the basis of Rayleigh and Thomson scattering.