2,985 research outputs found
Is There a Difference between âYouâ and âIâ? A Psycholinguistic Investigation of the Chinese Reflexive Ziji
We report two experiments examining first/second-person blocking effects on the Chinese long-distance reflexive ziji during on-line processing. Participants read sentences with varying matrix and embedded subjects (Exp1: 1st-person pronoun/3rd-person name; Exp2: 2nd-person pronoun/3rd-person name) and answered comprehension questions probing their interpretations of ziji. Work on English found that structurally inaccessible referents can cause competition at the reflexive, indicated by reading-time slowdowns (Badecker and Straub 2002). In Exp1, the 1st-person blocking condition (3rd-person matrix/1st-person embedded) exhibited slowdowns and a higher-than-expected rate of matrix-subject-interpretations, suggesting 1st-person blocking is not consistently effective. However, the subset of trials with effective blocking (local-antecedent interpretations) revealed no slowdowns. In Exp2, the 2nd-person blocking condition (3rd-person matrix/2nd-person embedded) showed consistent blocking and no significant slowdowns. Our results suggest that referentsâ ability to compete depends not only on prominence (Badecker and Straub 2002) but also how it is blocked (person-feature vs. syntactic barrier). Building upon BrunyĂ© et al.âs (2009) finding that 2nd-person pronouns are more effective at triggering perspective-taking than 1st-person pronouns, we suggest that the difference between first- and second- person blocking may be attributable to perspective taking: Identifying with the 2nd-person addressee leads comprehenders to more consistently interpret the reflexive as referring to the local 2nd-person subject, resulting in a consistent blocking effect
Electric/magnetic reciprocity in premetric electrodynamics with and without magnetic charge, and the complex electromagnetic field
We extend an axiomatic approach to classical electrodynamics, which we
developed recently, to the case of non-vanishing magnetic charge. Then two
axioms, namely those of the existence of the Lorentz force (Axiom 2) and of
magnetic flux conservation (Axiom 3) have to be generalized. Electric/magnetic
reciprocity constitutes a guiding principle for this undertaking. The extension
of the axioms can be implemented at a premetric stage, i.e., when metric and
connection of spacetime don't play a role. Complex Riemann-Silberstein fields
of the form have a natural place in the
theory, independent of the Hodge duality mapping defined by any particular
metric.Comment: 13 pages in latex, 3 references added, text slightly revise
A Parameter-free Statistical Measurement of Halos with Power Spectra
We show that, in the halo model of large-scale structure formation, the
difference between the Fourier and the DWT (discrete wavelet transform) power
spectra provides a statistical measurement of the halos. This statistical
quantity is free from parameters related to the shape of the mass profile and
the identification scheme of halos. That is, the statistical measurement is
invariant in the sense that models with reasonably defined and selected
parameters of the halo models should yield the same difference of the Fourier
and DWT spectra. This feature is useful to extract ensemble averaged properties
of halos, which cannot be obtained with the identification of individual halo.
To demonstrate this point, we show with WIGEON hydrodynamical simulation
samples that the spectrum difference provides a quantitative measurement of the
discrepancy of the distribution of baryonic gas from that of the underlying
dark matter field within halos. We also show that the mass density profile of
halos in physical space can be reconstructed with this statistical measurement.
This profile essentially is the average over an ensemble of halos, including
well virialized halos as well as halos with significant internal substructures.
Moreover, this reconstruction is sensitive to the tail of the mass density
profile. We showed that the profile with tail gives very different
result from that of . Other possible applications of this method are
discussed as well.Comment: To appear in ApJ, final versio
Rapid contextualization of fragmented scene information in the human visual system
Real-world environments are extremely rich in visual information. At any given moment in time, only a fraction of this information is available to the eyes and the brain, rendering naturalistic vision a collection of incomplete snapshots. Previous research suggests that in order to successfully contextualize this fragmented information, the visual system sorts inputs according to spatial schemata, that is knowledge about the typical composition of the visual world. Here, we used a large set of 840 different natural scene fragments to investigate whether this sorting mechanism can operate across the diverse visual environments encountered during real-world vision. We recorded brain activity using electroencephalography (EEG) while participants viewed incomplete scene fragments at fixation. Using representational similarity analysis on the EEG data, we tracked the fragments' cortical representations across time. We found that the fragments' typical vertical location within the environment (top or bottom) predicted their cortical representations, indexing a sorting of information according to spatial schemata. The fragments' cortical representations were most strongly organized by their vertical location at around 200ms after image onset, suggesting rapid perceptual sorting of information according to spatial schemata. In control analyses, we show that this sorting is flexible with respect to visual features: it is neither explained by commonalities between visually similar indoor and outdoor scenes, nor by the feature organization emerging from a deep neural network trained on scene categorization. Demonstrating such a flexible sorting across a wide range of visually diverse scenes suggests a contextualization mechanism suitable for complex and variable real-world environments
X-ray Emission of Baryonic Gas in the Universe: Luminosity-Temperature Relationship and Soft-Band Background
We study the X-ray emission of baryon fluid in the universe using the WIGEON
cosmological hydrodynamic simulations. It has been revealed that cosmic baryon
fluid in the nonlinear regime behaves like Burgers turbulence, i.e. the fluid
field consists of shocks. Like turbulence in incompressible fluid, the Burgers
turbulence plays an important role in converting the kinetic energy of the
fluid to thermal energy and heats the gas. We show that the simulation sample
of the CDM model without adding extra heating sources can fit well the
observed distributions of X-ray luminosity versus temperature ( vs.
) of galaxy groups and is also consistent with the distributions of X-ray
luminosity versus velocity dispersion ( vs. ). Because the
baryonic gas is multiphase, the and
distributions are significantly scattered. If we describe the relationships by
power laws and , we find and . The
X-ray background in the soft keV band emitted by the baryonic gas in
the temperature range K has also been calculated. We show that of
the total background, (1) no more than 2% comes from the region with
temperature less than K, and (2) no more than 7% is from the region
of dark matter with mass density . The
region of is generally clustered and
discretely distributed. Therefore, almost all of the soft X-ray background
comes from clustered sources, and the contribution from truly diffuse gas is
probably negligible. This point agrees with current X-ray observations.Comment: 32 pages including 14 figures and 2 tables. Final version for
publication in Ap
CP Violation in Hyperon Nonleptonic Decays within the Standard Model
We calculate the CP-violating asymmetries A(Lambda_-^0) and A(Xi_-^-) in
nonleptonic hyperon decay within the Standard Model using the framework of
heavy-baryon chiral perturbation theory (chiPT). We identify those terms that
correspond to previous calculations and discover several errors in the existing
literature. We present a new result for the lowest-order (in chiPT)
contribution of the penguin operator to these asymmetries, as well as an
estimate for the uncertainty of our result that is based on the calculation of
the leading nonanalytic corrections.Comment: 21 pages, 2 figures; discussion clarified, results & conclusions
unchanged, to appear in Phys. Rev.
Unbroken supersymmetry in the Aharonov-Casher effect
We consider the problem of the bound states of a spin 1/2 chargless particle
in a given Aharonov-Casher configuration. To this end we recast the description
of the system in a supersymmetric form. Then the basic physical requirements
for unbroken supersymmetry are established. We comment on the possibility of
neutron confinement in this system
New Physics and CP Violation in Hyperon Nonleptonic Decays
The sum of the CP-violating asymmetries A(Lambda_-^0) and A(Xi_-^-) in
hyperon nonleptonic decays is presently being measured by the E871 experiment.
We evaluate contributions to the asymmetries induced by chromomagnetic-penguin
operators, whose coefficients can be enhanced in certain models of new physics.
Incorporating recent information on the strong phases in Xi->Lambda pi decay,
we show that new-physics contributions to the two asymmetries can be
comparable. We explore how the upcoming results of E871 may constrain the
coefficients of the operators. We find that its preliminary measurement is
already better than the epsilon parameter of K-Kbar mixing in bounding the
parity-conserving contributions.Comment: 12 pages, 2 figure
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