760 research outputs found

    Do people's first names match their faces?

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    We often feel that people’s first names suit their faces in some way. Evidence has already shown that we share common stereotypes about how people with particular names should look. Here, we investigate whether there is any accuracy to these beliefs. Simply, can we match people’s names to their faces? Across two experiments, we tested whether American (Experiment 1) and British participants (Experiment 2) were able to match the first names of strangers with photographs of their faces. Although Experiment 1 provided some initial support for accuracy in female participants, we were unable to replicate this result in Experiment 2. Therefore, we find no overall evidence to suggest that particular names and faces are associated with each other

    Forgetting faces over a week: investigating self-reported face recognition ability and personality

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    Background Although face recognition is now well studied, few researchers have considered the nature of forgetting over longer time periods. Here, I investigated how newly learned faces were recognised over the course of one week. In addition, I considered whether self-reported face recognition ability, as well as Big Five personality dimensions, were able to predict actual performance in a recognition task. Methods In this experiment (N = 570), faces were learned through short video interviews, and these identities were later presented in a recognition test (using previously unseen images) after no delay, six hours, twelve hours, one day, or seven days. Results The majority of forgetting took place within the first 24 hours, with no significant decrease after that timepoint. Further, self-reported face recognition abilities were moderately predictive of performance, while extraversion showed a small, negative association with performance. In both cases, these associations remained consistent across delay conditions. Discussion The current work begins to address important questions regarding face recognition using longitudinal, real-world time intervals, focussing on participant insight into their own abilities, and the process of forgetting more generally

    Static wormholes on the brane inspired by Kaluza-Klein gravity

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    We use static solutions of 5-dimensional Kaluza-Klein gravity to generate several classes of static, spherically symmetric spacetimes which are analytic solutions to the equation (4)R=0^{(4)}R = 0, where (4)R^{(4)}R is the four-dimensional Ricci scalar. In the Randall & Sundrum scenario they can be interpreted as vacuum solutions on the brane. The solutions contain the Schwarzschild black hole, and generate new families of traversable Lorenzian wormholes as well as nakedly singular spacetimes. They generalize a number of previously known solutions in the literature, e.g., the temporal and spatial Schwarzschild solutions of braneworld theory as well as the class of self-dual Lorenzian wormholes. A major departure of our solutions from Lorenzian wormholes {\it a la} Morris and Thorne is that, for certain values of the parameters of the solutions, they contain three spherical surfaces (instead of one) which are extremal and have finite area. Two of them have the same size, meet the "flare-out" requirements, and show the typical violation of the energy conditions that characterizes a wormhole throat. The other extremal sphere is "flaring-in" in the sense that its sectional area is a local maximum and the weak, null and dominant energy conditions are satisfied in its neighborhood. After bouncing back at this second surface a traveler crosses into another space which is the double of the one she/he started in. Another interesting feature is that the size of the throat can be less than the Schwarzschild radius 2M2 M, which no longer defines the horizon, i.e., to a distant observer a particle or light falling down crosses the Schwarzschild radius in a finite time

    Stephani-Schutz quantum cosmology

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    We study the Stephani quantum cosmological model in the presence of a cosmological constant in radiation dominated Universe. In the present work the Schutz's variational formalism which recovers the notion of time is applied. This gives rise to Wheeler-DeWitt equations which can be cast in the form of Schr\"odinger equations for the scale factor. We find their eigenvalues and eigenfunctions by using the Spectral Method. Then we use the eigenfunctions in order to construct wave packets and evaluate the time-dependent expectation value of the scale factor, which is found to oscillate between non-zero finite maximum and minimum values. Since the expectation value of the scale factor never tends to the singular point, we have an initial indication that this model may not have singularities at the quantum level.Comment: 6 pages, 4 figures, 1 table, to appear in PL

    Hyper-realistic Face Masks in a Live Passport-Checking Task

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    Hyper-realistic face masks have been used as disguises in at least one border crossing and in numerous criminal cases. Experimental tests using these masks have shown that viewers accept them as real faces under a range of conditions. Here, we tested mask detection in a live identity verification task. Fifty-four visitors at the London Science Museum viewed a mask wearer at close range (2 m) as part of a mock passport check. They then answered a series of questions designed to assess mask detection, while the masked traveller was still in view. In the identity matching task, 8% of viewers accepted the mask as matching a real photo of someone else, and 82% accepted the match between masked person and masked photo. When asked if there was any reason to detain the traveller, only 13% of viewers mentioned a mask. A further 11% picked disguise from a list of suggested reasons. Even after reading about mask-related fraud, 10% of viewers judged that the traveller was not wearing a mask. Overall, mask detection was poor and was not predicted by unfamiliar face matching performance. We conclude that hyper-realistic face masks could go undetected during live identity checks

    Geodesic motions in extraordinary string geometry

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    The geodesic properties of the extraordinary vacuum string solution in (4+1) dimensions are analyzed by using Hamilton-Jacobi method. The geodesic motions show distinct properties from those of the static one. Especially, any freely falling particle can not arrive at the horizon or singularity. There exist stable null circular orbits and bouncing timelike and null geodesics. To get into the horizon {or singularity}, a particle need to follow a non-geodesic trajectory. We also analyze the orbit precession to show that the precession angle has distinct features for each geometry such as naked singularity, black string, and wormhole.Comment: 15 pages, 11 figure

    Photoproduction of J/psi mesons at high energies in parton model and k_t-faktorization approach

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    We consider J/psi meson photoproduction on protons at high energies at the leading order in alpha_s using conventional parton model and k_t-factorization approach of QCD. It is shown that in the both cases the colour singlet mechanism gives correct description for experimental data from HERA for the total cross section and for the J/psi meson z-spectrum at realistic values of a c-quark mass and meson wave function at the origin Psi (0). At the same time our predictions for p_t-spectrum of J/psi meson and for p_t dependence of the spin parameter alpha obtained in k_t-factorization approach are very different from the results obtained in conventional parton model. Such a way the experimental study of a polarized J/psi meson production at the large p_t should be a direct test of BFKL gluons.Comment: LaTeX2e, 11 pages plus 8 fig. using epsfig.st

    Quarkonia Measurements with STAR

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    We report results on quarkonium production from the STAR experiment at the Relativistic Heavy-Ion Collider (RHIC). J/psi spectra in p+p and Cu+Cu collisions at sqrt(s) = 200 GeV with transverse momenta in the range of 0.5-14 GeV/c and 5-8 GeV/c, respectively, are presented. We find that for p_T > 5 GeV/c yields in p+p collisions are consistent with those in minimum-bias Cu+Cu collisions scaled with the respective number of binary nucleon-nucleon collisions. In this range the nuclear modification factor, R_AA, is measured to be 0.9+-0.2(stat). For the first time at RHIC, high-p_T J/psi-hadron correlations were studied in p+p collisions. Implications from our measurements on J/psi production mechanisms, constraints on open bottom yields, and J/psi dissociation mechanisms at high-p_T are discussed. In addition, we give a brief status of measurements of Upsilon production in p+p and Au+Au collisions and present projections of future quarkonia measurements based on an upgrades to the STAR detector and increased luminosity achieved through stochastic cooling of RHIC.Comment: 5 pages, 5 figures. Prepared for 3rd International Conference on Hard and Electromagnetic Probes of High-Energy Nuclear Collisions (Hard Probes 2008), A Toxa, Spain, June 8-14, 200

    Bose-Einstein Condensate in Weak 3d Isotropic Speckle Disorder

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    The effect of a weak three-dimensional (3d) isotropic laser speckle disorder on various thermodynamic properties of a dilute Bose gas is considered at zero temperature. First, we summarize the derivation of the autocorrelation function of laser speckles in 1d and 2d following the seminal work of Goodman. The goal of this discussion is to show that a Gaussian approximation of this function, proposed in some recent papers, is inconsistent with the general background of laser speckle theory. Then we propose a possible experimental realization for an isotropic 3d laser speckle potential and derive its corresponding autocorrelation function. Using a Fourier transform of that function, we calculate both condensate depletion and sound velocity of a Bose-Einstein condensate as disorder ensemble averages of such a weak laser speckle potential within a perturbative solution of the Gross-Pitaevskii equation. By doing so, we reproduce the expression of the normalfluid density obtained earlier within the treatment of Landau. This physically transparent derivation shows that condensate particles, which are scattered by disorder, form a gas of quasiparticles which is responsible for the normalfluid component

    Direct J/psi and psi' hadroproduction via fragmentation in the collinear parton model and k_T-factorization approach

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    The p_T-spectra for direct J/psi and psi' in hadroproduction at Tevatron energy have been calculated based on NRQCD formalism and fragmentation approximation in the collinear parton model and k_T-factorization approach. We have described the CDF data and obtained a good agreement between the predictions obtained in the parton model and k_T-factorization approach. We performed the calculations using the relevant leading order in alpha_s hard amplitudes and the equal values of the color-octet long-distance matrix elements for the both models.Comment: 10 pages, Latex, 4 eps figures, epsfig.sty, graphics.st
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