208 research outputs found
Fundamental Strings as Black Bodies
We show that the decay spectrum of massive excitations in perturbative string
theories is thermal when averaged over the (many) initial degenerate states. We
first compute the inclusive photon spectrum for open strings at the tree level
showing that a black body spectrum with the Hagedorn temperature emerges in the
averaging. A similar calculation for a massive closed string state with winding
and Kaluza-Klein charges shows that the emitted graviton spectrum is thermal
with a "grey-body" factor, which approaches one near extremality. These results
uncover a simple physical meaning of the Hagedorn temperature and provide an
explicit microscopic derivation of the black body spectrum from a unitary
matrix.Comment: some changes in the Discussion section and in the reference list. 11
pages, Late
Personal relative deprivation and pro-environmental intentions.
Personal relative deprivation (PRD; the belief that one is worse off than other people who are similar to oneself) is associated with a reduced willingness to delay gratification, lower prosociality, and increased materialism. These results suggest that PRD may play a role in shaping people's willingness to act to protect the natural environment. We report 3 studies that investigate a possible link between PRD and pro-environmental intentions (ENV). Study 1 was an exploratory study using a US sample; Studies 2 and 3 were pre-registered replications using UK and US samples, respectively. In each study, participants self-reported PRD and ENV; they also indicated their subjective social status (where they come on a national "ladder" of social class) and reported their income, education, age, and gender/sex. All three studies found a negative correlation between PRD and ENV. However, multiple regression analyses in which ENV was regressed on PRD and all other variables simultaneously indicated that the unique effect of PRD was small and, for Studies 2 and 3, the 95% confidence intervals included zero. No other variable emerged as a clear unique predictor across all three studies. The data suggest that PRD may be associated with reduced intention to act pro-environmentally, but the causal status of this association, and its relationship to other demographic and social-status variables, remains a topic for further research
Immanent justice reasoning by spatial proximity
Immanent justice reasoning involves causally attributing someone’s bad outcome to their prior immoral actions. Building on the idea that causality is mentally linked with spatial proximity, we investigated whether such reasoning might lead participants to spatially bind together immoral actions and bad outcomes. Across 4 experiments (N = 553 Mechanical Turk workers), participants positioned sentences describing other people’s bad (vs. good) outcomes closer in space to previous immoral behaviours. This effect was observed both when the position of the initial action remained in a fixed location and when it “chased” the outcome across the screen. Importantly, we also found that this spatial positioning of immoral actions and bad outcomes is mediated by perceived deservingness of the outcome and is not merely due to perceived similarity of events. These findings suggest that perceived deservingness biases the spatial proximity of representations of others’ random bad outcomes and their prior immoral actions
K_{l 3} and \pi_{e 3} transition form factors
and transition form factors are calculated as an
application of Dyson-Schwinger equations. The role of nonanalytic contributions
to the quark--W-boson vertex is elucidated. A one-parameter model for this
vertex provides a uniformly good description of these transitions, including
the value of the scalar form factor of the kaon at the Callan-Treiman point.
The form factors, , are approximately linear on and have approximately the same slope. is a measure
of the Euclidean constituent-quark mass ratio: . In the isospin
symmetric limit: , the electromagnetic pion form factor,
and .Comment: 11 pages (incl. 3 figures), elsart.sty, epsf.st
Making sense of misfortune: Deservingness, self-esteem, and patterns of self-defeat.
Drawing on theorizing and research suggesting that people are motivated to view their world as an orderly and predictable place in which people get what they deserve, the authors proposed that (a) random and uncontrollable bad outcomes will lower self-esteem and (b) this, in turn, will lead to the adoption of self-defeating beliefs and behaviors. Four experiments demonstrated that participants who experienced or recalled bad (vs. good) breaks devalued their self-esteem (Studies 1a and 1b), and that decrements in self-esteem (whether arrived at through misfortune or failure experience) increase beliefs about deserving bad outcomes (Studies 1a, 1b, 2a, 2b). Five studies (Studies 3–7) extended these findings by showing that this, in turn, can engender a wide array of self-defeating beliefs and behaviors, including claimed self-handicapping ahead of an ability test (Study 3), the preference for others to view the self less favorably (Studies 4–5), chronic self-handicapping and thoughts of physical self-harm (Study 6), and choosing to receive negative feedback during an ability test (Study 7). The current findings highlight the important role that concerns about deservingness play in the link between lower self-esteem and patterns of self-defeating beliefs and behaviors. The theoretical and practical implications of these findings are discussed
Victims, Vignettes, and Videos: Meta-Analytic and Experimental Evidence that Emotional Impact Enhances the Derogation of Innocent Victims
Research during the 1960s found that observers could be moved enough by an innocent victim’s suffering to derogate their character. However, recent research has produced inconsistent evidence for this effect. We conducted the first meta-analysis (k = 55) of the experimental literature on the victim derogation effect to test the hypothesis that it varies as a function of the emotional impactfulness of the context for observers. We found that studies which employed more impactful contexts (e.g., that were real and vivid) reported larger derogation effects. Emotional impact was, however, confounded by year of appearance, such that older studies reported larger effects and were more impactful. To disentangle the role of emotional impact, in two primary experiments we found that more impactful contexts increased the derogation of an innocent victim. Overall, the findings advance our theoretical understanding of the contexts in which observers are more likely to derogate an innocent victim
Psychological strengths and well-being:Strengths use predicts quality of life, well-being and mental health in autism
Supplemental material, sj-docx-1-aut-10.1177_13623613221146440 for Psychological strengths and well-being: Strengths use predicts quality of life, well-being and mental health in autism by Emily C Taylor, Lucy A Livingston, Rachel A Clutterbuck, Mitchell J Callan and Punit Shah in Autism</p
Black Hole Evaporation along Macroscopic Strings
We develop the quantization of a macroscopic string which extends radially
from a Schwarzschild black hole. The Hawking process excites a thermal bath of
string modes that causes the black hole to lose mass. The resulting typical
string configuration is a random walk in the angular coordinates. We show that
the energy flux in string excitations is approximately that of spacetime field
modes.Comment: 26pp, EFI 93-73. (Original claim that string Hawking flux exceeds
spacetime flux is WRONG. It is the same; revised version provides correct
argument and additional comments.
The Interrelations Between Social Class, Personal Relative Deprivation, and Prosociality.
We propose that personal relative deprivation (PRD)-the belief that one is worse off than similar others-plays a key role in the link between social class and prosociality. Across multiple samples and measures (total N = 2,233), people higher in PRD were less inclined to help others. When considered in isolation, neither objective nor subjective socioeconomic status (SES) was meaningfully associated with prosociality. However, because people who believe themselves to be at the top of the socioeconomic hierarchy are typically low in PRD, these variables act as mutual suppressors-the predictive validity of both is enhanced when they are considered simultaneously, revealing that both higher subjective SES and higher PRD are associated with lower prosociality. These results cast new light on the complex connections between relative social status and people's willingness to act for the benefit of others.This research was supported by Grant RPG-2013-148 from the Leverhulme Trust and studentship ES/J500045/1 from the Economic and Social Research Council.This is the final version of the article. It first appeared from SAGE Publications via https://doi.org/10.1177/194855061667387
Self-gravitating fundamental strings and black-holes
The configuration of typical highly excited (M >> M_s ~ (alpha')^{-1/2})
string states is considered as the string coupling g is adiabatically
increased. The size distribution of very massive single string states is
studied and the mass shift, due to long-range gravitational, dilatonic and
axionic attraction, is estimated. By combining the two effects, in any number
of spatial dimensions d, the most probable size of a string state becomes of
order l_s = sqrt{2 alpha'} when g^2 M / M_s ~ 1. Depending on the dimension d,
the transition between a random-walk-size string state (for low g) and a
compact (~ l_s) string state (when g^2 M / M_s ~ 1) can be very gradual (d=3),
fast but continuous (d=4), or discontinuous (d > 4). Those compact string
states look like nuggets of an ultradense state of string matter, with energy
density rho ~ g^{-2} M_s^{d+1}. Our results extend and clarify previous work by
Susskind, and by Horowitz and Polchinski, on the correspondence between
self-gravitating string states and black holes.Comment: 28 pages, Revtex, minor misprints and references correcte
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