352 research outputs found
Choreography, controversy and child sex abuse: Theoretical reflections on a cultural criminological analysis of dance in a pop music video
This article was inspired by the controversy over claims of ‘pedophilia!!!!’ undertones and the ‘triggering’ of memories of childhood sexual abuse in some viewers by the dance performance featured in the music video for Sia’s ‘Elastic Heart’ (2015). The case is presented for acknowledging the hidden and/or overlooked presence of dance in social scientific theory and cultural studies and how these can enhance and advance cultural criminological research. Examples of how these insights have been used within other disciplinary frameworks to analyse and address child sex crime and sexual trauma are provided, and the argument is made that popular cultural texts such as dance in pop music videos should be regarded as significant in analysing and tracing public perceptions and epistemologies of crimes such as child sex abuse
Cosmology With Many Light Scalar Fields: Stochastic Inflation and Loop Corrections
We explore the consequences of the existence of a very large number of light
scalar degrees of freedom in the early universe. We distinguish between
participator and spectator fields. The former have a small mass, and can
contribute to the inflationary dynamics; the latter are either strictly
massless or have a negligible VEV. In N-flation and generic assisted inflation
scenarios, inflation is a co-operative phenomenon driven by N participator
fields, none of which could drive inflation on their own. We review upper
bounds on N, as a function of the inflationary Hubble scale H. We then consider
stochastic and eternal inflation in models with N participator fields showing
that individual fields may evolve stochastically while the whole ensemble
behaves deterministically, and that a wide range of eternal inflationary
scenarios are possible in this regime. We then compute one-loop quantum
corrections to the inflationary power spectrum. These are largest with N
spectator fields and a single participator field, and the resulting bound on N
is always weaker than those obtained in other ways. We find that loop
corrections to the N-flation power spectrum do not scale with N, and thus place
no upper bound on the number of participator fields. This result also implies
that, at least to leading order, the theory behaves like a composite single
scalar field. In order to perform this calculation, we address a number of
issues associated with loop calculations in the Schwinger-Keldysh "in-in"
formalism.Comment: Typos corrected. Matches published versio
Constraining the Inflationary Equation of State
We explore possible constraints on the inflationary equation state: p=w\rho.
While w must be close to -1 for those modes that contribute to the observed
power spectrum, for those modes currently out of experimental reach, the
constraints on w are much weaker, with only w<-1/3 as an a priori requirement.
We find, however, that limits on the reheat temperature and the inflationary
energy scale constrain w further, though there is still ample parameter space
for a vastly different (accelerating) equation of state between the end of
quasi-de Sitter inflation and the beginning of the radiation-dominated era. In
the event that such an epoch of acceleration could be observed, we review the
consequences for the primordial power spectrum.Comment: 12 pages, 2 figur
Inflation and the Scale Dependent Spectral Index: Prospects and Strategies
We consider the running of the spectral index as a probe of both inflation
itself, and of the overall evolution of the very early universe. Surveying a
collection of simple single field inflationary models, we confirm that the
magnitude of the running is relatively consistent, unlike the tensor amplitude,
which varies by orders of magnitude. Given this target, we confirm that the
running is potentially detectable by future large scale structure or 21 cm
observations, but that only the most futuristic measurements can distinguish
between these models on the basis of their running. For any specified
inflationary scenario, the combination of the running index and unknown
post-inflationary expansion history induces a theoretical uncertainty in the
predicted value of the spectral index. This effect can easily dominate the
statistical uncertainty with which Planck and its successors are expected to
measure the spectral index. More positively, upcoming cosmological experiments
thus provide an intriguing probe of physics between TeV and GUT scales by
constraining the reheating history associated with any specified inflationary
model, opening a window into the "primordial dark age" that follows the end of
inflation.Comment: 32 pages. v2 and v3 Minor reference updates /clarification
Constraining holographic inflation with WMAP
In a class of recently proposed models, the early universe is strongly
coupled and described holographically by a three-dimensional, weakly coupled,
super-renormalizable quantum field theory. This scenario leads to a power
spectrum of scalar perturbations that differs from the usual empirical LCDM
form and the predictions of generic models of single field, slow roll
inflation. This spectrum is characterized by two parameters: an amplitude, and
a parameter g related to the coupling constant of the dual theory. We estimate
these parameters, using WMAP and other astrophysical data. We compute Bayesian
evidence for both the holographic model and standard LCDM and find that their
difference is not significant, although LCDM provides a somewhat better fit to
the data. However, it appears that Planck will permit a definitive test of this
holographic scenario.Comment: 24 pages, 9 figs, published versio
Male frequent attenders of general practice and their help seeking preferences
Background: Low rates of health service usage by men are commonly linked to masculine values and traditional male gender roles. However, not all men conform to these stereotypical notions of masculinity, with some men choosing to attend health services on a frequent basis, for a variety of different reasons. This study draws upon the accounts of male frequent attenders of the General Practitioner's (GP) surgery, examining their help-seeking preferences and their reasons for choosing services within general practice over other sources of support. Methods: The study extends thematic analysis of interview data from the Self Care in Primary Care study (SCinPC), a large scale multi-method evaluation study of a self care programme delivered to frequent attenders of general practice. Data were collected from 34 semi-structured interviews conducted with men prior to their exposure to the intervention. Results: The ages of interviewed men ranged from 16 to 72 years, and 91% of the sample (n= 31) stated that they had a current health condition. The thematic analysis exposed diverse perspectives within male help-seeking preferences and the decision-making behind men's choice of services. The study also draws attention to the large variation in men's knowledge of available health services, particularly alternatives to general practice. Furthermore, the data revealed some men's lack of confidence in existing alternatives to general practice. Conclusions: The study highlights the complex nature of male help-seeking preferences, and provides evidence that there should be no 'one size fits all' approach to male service provision. It also provides impetus for conducting further studies into this under researched area of interest. © 2011 WPMH GmbH
Higher Order Corrections to the Primordial Gravitational Wave Spectrum and its Impact on Parameter Estimates for Inflation
We study the impact of the use of the power series expression for the
primordial tensor spectrum on parameter estimation from future direct detection
gravitational wave experiments. The spectrum approximated by the power series
expansion may give large deviation from the true (fiducial) value when it is
normalized at CMB scale because of the large separation between CMB and direct
detection scales. We derive the coefficients of the higher order terms of the
expansion up to the sixth order within the framework of the slow-roll
approximation and investigate how well the inclusion of higher order terms
improves the analytic prediction of the spectrum amplitude by comparing with
numerical results. Using the power series expression, we consider future
constraints on inflationary parameters expected from direct detection
experiments of the inflationary gravitational wave background and show that the
truncation of the higher order terms can lead to incorrect evaluation of the
parameters. We present two example models; a quadratic chaotic inflation model
and mixed inflaton and curvaton model with a quartic inflaton potential.Comment: 25 pages, 7 figures, revised version accepted by JCA
Running Spectral Index and Formation of Primordial Black Hole in Single Field Inflation Models
A broad range of single field models of inflation are analyzed in light of
all relevant recent cosmological data, checking whether they can lead to the
formation of long-lived Primordial Black Holes (PBHs). To that end we calculate
the spectral index of the power spectrum of primordial perturbations as well as
its first and second derivatives. PBH formation is possible only if the
spectral index increases significantly at small scales, i.e. large wave number
. Since current data indicate that the first derivative of the
spectral index is negative at the pivot scale , PBH formation
is only possible in the presence of a sizable and positive second derivative
("running of the running") . Among the three small-field and five
large-field models we analyze, only one small-field model, the "running mass"
model, allows PBH formation, for a narrow range of parameters. We also note
that none of the models we analyze can accord for a large and negative value of
, which is weakly preferred by current data.Comment: 26 pages, 5 figures, Refs. added, Minor textual change; version to
appear in JCA
Primordial Black Holes, Eternal Inflation, and the Inflationary Parameter Space after WMAP5
We consider constraints on inflation driven by a single, minimally coupled
scalar field in the light of the WMAP5 dataset, as well as ACBAR and the
SuperNova Legacy Survey. We use the Slow Roll Reconstruction algorithm to
derive optimal constraints on the inflationary parameter space. The scale
dependence in the slope of the scalar spectrum permitted by WMAP5 is large
enough to lead to viable models where the small scale perturbations have a
substantial amplitude when extrapolated to the end of inflation. We find that
excluding parameter values which would cause the overproduction of primordial
black holes or even the onset of eternal inflation leads to potentially
significant constraints on the slow roll parameters. Finally, we present a more
sophisticated approach to including priors based on the total duration of
inflation, and discuss the resulting restrictions on the inflationary parameter
space.Comment: v2: version published in JCAP. Minor clarifications and references
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