4,143 research outputs found
Non-rigidity of spherical inversive distance circle packings
We give a counterexample of Bowers-Stephenson's conjecture in the spherical
case: spherical inversive distance circle packings are not determined by their
inversive distances.Comment: 6 pages, one pictur
VPI-7: The First Zincosilicate Molecular Sieve Containing Three-membered T-Atom Rings
VPI-7: the first microporous zincosilicate to contain 3-membered rings (3MR) is reported
Minimal surfaces and particles in 3-manifolds
We use minimal (or CMC) surfaces to describe 3-dimensional hyperbolic,
anti-de Sitter, de Sitter or Minkowski manifolds. We consider whether these
manifolds admit ``nice'' foliations and explicit metrics, and whether the space
of these metrics has a simple description in terms of Teichm\"uller theory. In
the hyperbolic settings both questions have positive answers for a certain
subset of the quasi-Fuchsian manifolds: those containing a closed surface with
principal curvatures at most 1. We show that this subset is parameterized by an
open domain of the cotangent bundle of Teichm\"uller space. These results are
extended to ``quasi-Fuchsian'' manifolds with conical singularities along
infinite lines, known in the physics literature as ``massive, spin-less
particles''.
Things work better for globally hyperbolic anti-de Sitter manifolds: the
parameterization by the cotangent of Teichm\"uller space works for all
manifolds. There is another description of this moduli space as the product two
copies of Teichm\"uller space due to Mess. Using the maximal surface
description, we propose a new parameterization by two copies of Teichm\"uller
space, alternative to that of Mess, and extend all the results to manifolds
with conical singularities along time-like lines. Similar results are obtained
for de Sitter or Minkowski manifolds.
Finally, for all four settings, we show that the symplectic form on the
moduli space of 3-manifolds that comes from parameterization by the cotangent
bundle of Teichm\"uller space is the same as the 3-dimensional gravity one.Comment: 53 pages, no figure. v2: typos corrected and refs adde
The Parkes Elvis Festival: Attendee and host community perspectives
Each year, up to 20,000 people descend upon the rural town of Parkes, 365km west of Sydney, to attend the Parkes Elvis Festival. Initiated in 1993 by a group of locals who were Elvis Presley fans, the annual festival has grown from the humble beginnings of a one-day event with a few hundred attendees to a five day festival. In a bid to assist the festival organisers to understand the impacts of the Parkes Elvis Festival on both attendees and the host community, researchers designed a set of survey instruments to deliver a comprehensive evaluation of the social and economic impacts of the festival. Research was carried out in 2010 and separate surveys were conducted for festival organisers, attendees and local residents. After a brief explanation of the festival, and the man it is inspired by, this chapter explores the methods used to collect data before outlining the results. The results are divided into two key sections, attendees’ perceptions, and host community perceptions. First we profile the demographics, motivations and experience of festival attendees. Second, we profile the perceptions of the host community with respect to both the economic and social impacts of the festival. The surveys demonstrate the overwhelming goodwill and enthusiasm for the festival, by both the host community and attendees. Results show that the festival attracts a mix of first time and repeat visitors, and that many of the returning attendees do so to catch up with friends made at previous festivals. For residents, regardless of whether they attend or not, the large majority understand the economic, tourism and community benefits generated by the festival
Luttinger liquid ARPES spectra from samples of LiMoO grown by the temperature gradient flux technique
Angle resolved photoemission spectroscopy line shapes measured for
quasi-one-dimensional LiMoO samples grown by a temperature
gradient flux technique are found to show Luttinger liquid behavior, consistent
with all previous data by us and other workers obtained from samples grown by
the electrolyte reduction technique. This result eliminates the sample growth
method as a possible origin of considerable differences in photoemission data
reported in previous studies of LiMoO.Comment: Some text adde
Refusing to Endorse. A must Explanation for Pejoratives.
In her analysis of pejoratives, Eva Picardi rejects a too sharp separation between descriptive and expressive content. I reconstruct some of her arguments, endorsing Eva’s criticism of Williamson’s analysis of Dummett and developing a suggestion by Manuel Garcia Carpintero on a speech act analysis of pejoratives. Eva’s main concern is accounting for our instinctive refusal to endorse an assertion containing pejoratives because it suggests a picture of reality we do not share. Her stance might be further developed claiming that uses of pejoratives not only suggest, but also promote a wrong picture of reality. Our refusal to endorse implies rejecting not only a wrong picture of reality but also a call for participation to what that
picture promotes
Self-Presentational Determinants of Sex Differences in Leadership Behavior
Men and women placed in leadership positions communicated information about their skills and abilities to their subordinates. Although leaders’ perceptions of their abilities, group members’ knowledge of their leader’s abilities, and the specific skills needed by the leader were all manipulated in the experimental setting, self-presentations of ability were primarily determined by sex role stereotypes rather than by situational factors. Results indicated that (1) male leaders emphasized their social influence and task abilities; (2) female leaders emphasized their interpersonal, socioemotional abilities; and (3) group members felt task ability, as compared to interpersonal ability, was a far more important skill for a leader to possess. It was concluded that sex differences in male and female leadership behavior may be due to self-presentational conformity to sex roles, and that this conformity enhances males’ leadership effectiveness while detracting from females’ leadership effectiveness
Possible observation of parametrically amplified coherent phasons in K0.3MoO3 using time-resolved extreme-ultraviolet ARPES
We use time- and angle-resolved photoemission spectroscopy (tr-ARPES) in the
Extreme Ultraviolet (EUV) to measure the time- and momentum-dependent
electronic structure of photo-excited K0.3MoO3. Prompt depletion of the Charge
Density Wave (CDW) condensate launches coherent oscillations of the amplitude
mode, observed as a 1.7-THz-frequency modulation of the bonding band position.
In contrast, the anti-bonding band oscillates at about half this frequency. We
attribute these oscillations to coherent excitation of phasons via parametric
amplification of phase fluctuations.Comment: 4 figure
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