Mental state attribution and the gaze cueing effect

Theory of mind is said to be possessed by an individual if he or she is able to impute mental states to others. Recently, some authors have demonstrated that such mental state attributions can mediate the “gaze cueing” effect, in which observation of another individual shifts an observer’s attention. One question that follows from this work is whether such mental state attributions produce mandatory modulations of gaze cueing. Employing the basic gaze cueing paradigm, together with a technique commonly used to assess mental-state attribution in nonhuman animals, we manipulated whether the gazing agent could see the same thing as the participant (i.e., the target) or had this view obstructed by a physical barrier. We found robust gaze cueing effects, even when the observed agent in the display could not see the same thing as the participant. These results suggest that the attribution of “seeing” does not necessarily modulate the gaze cueing effect

A Case of Offspring Adoption in Free-ranging Polar Bears (Ursus Maritimus)

During a study of the reproductive ecology of polar bears (Ursus maritimus) in western Hudson Bay (Canada), we documented a case of litter adoption. In an eight-month period, a ten-year-old adult female lost a litter of two cubs-of-the-year and adopted three other cubs-of-the-year. This is the first reported case of natural offspring adoption in polar bears, and its significance as a reproductive strategy is unknown. Nevertheless, the observation raised questions regarding the social circumstances under which adoption may occur and the benefits or costs to maternal fitness in a solitary mammal such as the polar bear.Au cours d'une étude portant sur l'écologie de la reproduction des ours polaires (Ursus maritimus) dans la partie ouest de la baie d'Hudson (Canada), on a documenté un cas d'adoption de litière. Au cours d'une période de huit mois, une femelle adulte de dix ans a perdu sa litière de deux petits âgés de moins d'un an et adopté trois autres petits de l'année. Cet événement est le premier cas d'adoption naturelle que l'on ait rapporté chez l'ours polaire, et on n'en a pas encore mesuré l'importance en tant que stratégie de reproduction. L'observation soulève cependant des questions concernant les conditions sociales dans lesquelles peut se produire l'adoption et les avantages ou les coûts pour la santé maternelle chez un mammifère solitaire tel que l'ours polaire

The Quark-Photon Vertex and the Pion Charge Radius

The rainbow truncation of the quark Dyson-Schwinger equation is combined with the ladder Bethe-Salpeter equation for the dressed quark-photon vertex to study the low-momentum behavior of the pion electromagnetic form factor. With model gluon parameters previously fixed by the pion mass and decay constant, the pion charge radius $r_\pi$ is found to be in excellent agreement with the data. When the often-used Ball-Chiu Ansatz is used to construct the quark-photon vertex directly from the quark propagator, less than half of $r_\pi^2$ is generated. The remainder of $r^2_\pi$ is seen to be attributable to the presence of the $\rho$-pole in the solution of the ladder Bethe-Salpeter equation.Comment: 21 pages, 9 figure

Birkhoff type decompositions and the Baker-Campbell-Hausdorff recursion

We describe a unification of several apparently unrelated factorizations arisen from quantum field theory, vertex operator algebras, combinatorics and numerical methods in differential equations. The unification is given by a Birkhoff type decomposition that was obtained from the Baker-Campbell-Hausdorff formula in our study of the Hopf algebra approach of Connes and Kreimer to renormalization in perturbative quantum field theory. There we showed that the Birkhoff decomposition of Connes and Kreimer can be obtained from a certain Baker-Campbell-Hausdorff recursion formula in the presence of a Rota-Baxter operator. We will explain how the same decomposition generalizes the factorization of formal exponentials and uniformization for Lie algebras that arose in vertex operator algebra and conformal field theory, and the even-odd decomposition of combinatorial Hopf algebra characters as well as to the Lie algebra polar decomposition as used in the context of the approximation of matrix exponentials in ordinary differential equations.Comment: accepted for publication in Comm. in Math. Phy

Fokker-Planck equations and density of states in disordered quantum wires

We propose a general scheme to construct scaling equations for the density of states in disordered quantum wires for all ten pure Cartan symmetry classes. The anomalous behavior of the density of states near the Fermi level for the three chiral and four Bogoliubov-de Gennes universality classes is analysed in detail by means of a mapping to a scaling equation for the reflection from a quantum wire in the presence of an imaginary potential.Comment: 10 pages, 5 figures, revised versio

The Gribov-Zwanziger action in the presence of the gauge invariant, nonlocal mass operator Tr∫d4xFμν(D2)−1FμνTr \int d^4x F_{\mu\nu} (D^2)^{-1} F_{\mu\nu} in the Landau gauge

We prove that the nonlocal gauge invariant mass dimension two operator $F_{\mu\nu} (D^2)^{-1} F_{\mu\nu}$ can be consistently added to the Gribov-Zwanziger action, which implements the restriction of the path integral's domain of integration to the first Gribov region when the Landau gauge is considered. We identify a local polynomial action and prove the renormalizability to all orders of perturbation theory by employing the algebraic renormalization formalism. Furthermore, we also pay attention to the breaking of the BRST invariance, and to the consequences that this has for the Slavnov-Taylor identity.Comment: 30 page

Analysis of a quenched lattice-QCD dressed-quark propagator

Quenched lattice-QCD data on the dressed-quark Schwinger function can be correlated with dressed-gluon data via a rainbow gap equation so long as that equation's kernel possesses enhancement at infrared momenta above that exhibited by the gluon alone. The required enhancement can be ascribed to a dressing of the quark-gluon vertex. The solutions of the rainbow gap equation exhibit dynamical chiral symmetry breaking and are consistent with confinement. The gap equation and related, symmetry-preserving ladder Bethe-Salpeter equation yield estimates for chiral and physical pion observables that suggest these quantities are materially underestimated in the quenched theory: |<bar-q q>| by a factor of two and f_pi by 30%.Comment: 9 pages, LaTeX2e, REVTEX4, 6 figure

Observation of a New J(PC)=1(+-) Isoscalar State in the Reaction Pi- Proton -> Omega Eta Neutron at 18 GeV/c

Results are presented on a partial wave analysis of the Omega Eta final state produced in Pi- Proton interactions at 18 GeVc where Omega -> Pi+ Pi- Pi0, Pi0 -> 2 Gammas, and Eta -> 2 Gammas. We observe the previously unreported decay mode Omega(1650) -> Omega Eta and a new 1(+-) meson state h1(1595) with a mass M=1594(15)(+10)(-60) MeV/c^2 and a width Gamma=384(60)(+70)(-100) MeV/c^2. The h1(1595) state exhibits resonant-like phase motion relative to the Omega(1650).Comment: Submitted to Physics Letters B Eight total pages including 11 figures and 1 tabl

The radial curvature of an end that makes eigenvalues vanish in the essential spectrum II

Under the quadratic-decay-conditions of the radial curvatures of an end, we shall derive growth estimates of solutions to the eigenvalue equation and show the absence of eigenvalues.Comment: "$\ge$" in the conditions $(*_4)$ and $(*_5)$ should be replaced by "$>$". $\gamma \ge \frac{n-1}{2}(b-a)$ in the conclusion of Theorem 1.3 should be replaced by $\gamma > \frac{n-1}{2}(b-a)$; trivial miss-calculatio