18,354 research outputs found
The Green's function for the radial Schramm-Loewner evolution
We prove the existence of the Green's function for radial SLE(k) for k<8.
Unlike the chordal case where an explicit formula for the Green's function is
known for all values of k<8, we give an explicit formula only for k=4. For
other values of k, we give a formula in terms of an expectation with respect to
SLE conditioned to go through a point.Comment: v1: 16 pages, 0 figure
Conformal fields, restriction properties, degenerate representations and SLE
In this note, we show how to relate the Schramm-Loewner Evolution processes
(SLE) to highest-weight representations of the Virasoro Algebra. The conformal
restriction properties of SLE that have been recently studied in the paper
arXiv:math.PR/0209343 by G. Lawler, O. Schramm and the second author play an
instrumental role. In this setup, various considerations from conformal field
theory can be interpreted and reformulated via SLE. This enables to make a
concrete link between the two-dimensional discrete critical systems from
statistical physics and conformal field theory.Comment: To appear in C.R.Acad. Sci. Paris, Ser. I Math. Minor modifications
from the first versio
Improved Laboratory Transition Probabilities for Ce II, Application to the Cerium Abundances of the Sun and Five r-process Rich, Metal-Poor Stars, and Rare Earth Lab Data
Recent radiative lifetime measurements accurate to +/- 5% using laser-induced
fluorescence (LIF) on 43 even-parity and 15 odd-parity levels of Ce II have
been combined with new branching fractions measured using a Fourier transform
spectrometer (FTS) to determine transition probabilities for 921 lines of Ce
II. This improved laboratory data set has been used to determine a new solar
photospheric Ce abundance, log epsilon = 1.61 +/- 0.01 (sigma = 0.06 from 45
lines), a value in excellent agreement with the recommended meteoritic
abundance, log epsilon = 1.61 +/- 0.02. Revised Ce abundances have also been
derived for the r-process-rich metal-poor giant stars BD+17 3248, CS 22892-052,
CS 31082-001, HD 115444 and HD 221170. Between 26 and 40 lines were used for
determining the Ce abundance in these five stars, yielding a small statistical
uncertainty of 0.01 dex similar to the Solar result. The relative abundances in
the metal-poor stars of Ce and Eu, a nearly pure r-process element in the Sun,
matches r-process only model predictions for Solar System material. This
consistent match with small scatter over a wide range of stellar metallicities
lends support to these predictions of elemental fractions. A companion paper
includes an interpretation of these new precision abundance results for Ce as
well as new abundance results and interpretations for Pr, Dy and Tm.Comment: 84 pages, 8 Figures, 14 Tables; To appear in the Astrophysical
Journal Supplemen
A Lower Bound on the Growth Exponent for Loop-Erased Random Walk in Two Dimensions
The growth exponent for loop-erased or Laplacian random walk on the
integer lattice is defined by saying that the expected time to reach the sphere
of radius is of order . We prove that in two dimensions, the
growth exponent is strictly greater than one. The proof uses a known estimate
on the third moment of the escape probability and an improvement on the
discrete Beurling projection theorem
Affect and Group Attachments: The Role of Shared Responsibility
This paper theorizes the role of shared responsibility in the development of affective group attachments, interweaving ideas from social exchange and social identity theories. The main arguments are that (1) people engaged in task interaction experience positive or negative emotions from those interactions; (2) tasks that promote more sense of shared responsibility across members lead people to attribute their individual emotions to groups or organizations; and (3) group attributions of own emotions are the basis for stronger or weaker group attachments. The paper suggests that social categorization and structural interdependence promote group attachments by producing task interactions that have positive emotional effects on those involved
Testimony of John J. Lawler Before the Commission on the Future of Worker-Management Relations
Testimony_Lawler_022494.pdf: 224 downloads, before Oct. 1, 2020
Neuroimaging of Habit-based vs. Goal-directed behavior in Instrumental Learning
Addiction has been proposed to result from an overreliance on the habit-based and goal-directed controllers of behavior; however, few data exist to simultaneously support both behavioral and neuoranatomical aspects of this theory in humans. Here, we clarify the locations of the homologous structures controlling behavior in the human brain to those studied in animal models. The study included two parts. 1) The first part established in a behavioral experiment that the devaluation video in the present paradigm was able to influence instrumental behavior. Using a 3-session instrumental learning task to examine behavior, we examined 78 participants, aged 18-35. A significant difference in the change in response rate immediately before and after devaluation was found between the 2 groups viewing worms in devaluation compared to the group not viewing worms. There was a significant difference in change in liking immediately before and after devaluation between the three conditions, as well as in the change in liking, hunger, and response rate between the paired and empty bowl unpaired conditions. There was a significant correlation between snack liking pre-session 3 and response rate in session 3, as well as between pre-extinction snack liking and response rate in the start of extinction.
2) The second part of the study used the same 3-session training paradigm over 3-days, with fMRI on the third day to measure neural activity during this same instrumental learning task. Although the results are preliminary (N=10), these show that the comparable regions of the human brain are involved in goal-directed and habit-based control of behavior, with a perfect negative Spearman correlation of mean vmPFC activity at the end of training and the change in responding from immediately before to immediately after devaluation.
Three of the 10 subjects were addicted smokers, which is insufficient data to determine whether they were less sensitive to reward devaluation and whether they relied more heavily on brain structures associated with habit-based controllers of behavior. However, understanding the relationship between habit-based and goal-directed controllers of behavior and their role in addiction and clarifying the human brain structures responsible for these systems can lead to the development of therapies for addiction
Foreword
[Excerpt] This volume is designed to commemorate the distinguished history of the New York State School of Industrial and Labor Relations at Cornell University, especially the various disciplines and fields that are inter-woven within its domain. For this book, many of those who have been a significant part of the ILR School’s history were invited to write a scholarly overview of some aspect of industrial and labor relations. These essays analyze developments in one or more of the various subfields in which many of the school’s alumni and faculty have been so active and prominent. The volume is being published by the ILR School on the occasion of the formal dedication of a new classroom and library complex
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