5,989 research outputs found
Mass as a Relativistic Quantum Observable
A field state containing photons propagating in different directions has a
non vanishing mass which is a quantum observable. We interpret the shift of
this mass under transformations to accelerated frames as defining space-time
observables canonically conjugated to energy-momentum observables. Shifts of
quantum observables differ from the predictions of classical relativity theory
in the presence of a non vanishing spin. In particular, quantum redshift of
energy-momentum is affected by spin. Shifts of position and energy-momentum
observables however obey simple universal rules derived from invariance of
canonical commutators.Comment: 5 pages, revised versio
HIV infection and domestic smoke exposure, but not human papillomavirus, are risk factors for esophageal squamous cell carcinoma in Zambia: a case-control study
(c) 2015 The Authors. Cancer Medicine published by John Wiley & Sons Ltd. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited
Clinical management of common presentations of patients diagnosed with BPD during the COVID-19 pandemic: The contribution of the MBT framework
The coronavirus (COVID-19) pandemic has both a profound effect on mental health and affects how psychosocial interventions are delivered. In this paper, we outline particular difficulties patients with Borderline Personality Disorder (BPD) may encounter as a result of the pandemic. We also consider changes in the provision of treatment, specifically the transition from face to face encounters to remotely delivered sessions. Building on a mentalization-based developmental framework, we use clinical vignettes to chart some of these challenges for patients, clinicians and teams. We then make practical recommendations for adaptations to work during the pandemic via the phone or video-link with BPD patients and other groups characterized by a vulnerability to unstable and imbalanced mentalizing. We conclude that the response to these challenges benefits from an existing treatment context that aims at fostering mentalizing and resilience, in which practitioners address the hierarchy of patient needs and their individual responses to the experience of remote treatment during the COVID-19 pandemic
Arbitrary Rotation Invariant Random Matrix Ensembles and Supersymmetry
We generalize the supersymmetry method in Random Matrix Theory to arbitrary
rotation invariant ensembles. Our exact approach further extends a previous
contribution in which we constructed a supersymmetric representation for the
class of norm-dependent Random Matrix Ensembles. Here, we derive a
supersymmetric formulation under very general circumstances. A projector is
identified that provides the mapping of the probability density from ordinary
to superspace. Furthermore, it is demonstrated that setting up the theory in
Fourier superspace has considerable advantages. General and exact expressions
for the correlation functions are given. We also show how the use of hyperbolic
symmetry can be circumvented in the present context in which the non-linear
sigma model is not used. We construct exact supersymmetric integral
representations of the correlation functions for arbitrary positions of the
imaginary increments in the Green functions.Comment: 36 page
Comments on QED with background electric fields
It is well known that there is a total cancellation of the
\emph{factorizable} IR divergences in unitary interacting field theories, such
as QED and quantum gravity. In this note we show that such a cancellation does
not happen in QED with background electric fields which can produce pairs.
There is no factorization of the IR divergences.Comment: 14 pages, 1 figur
Perturbation theory in radial quantization approach and the expectation values of exponential fields in sine-Gordon model
A perturbation theory for Massive Thirring Model (MTM) in radial quantization
approach is developed. Investigation of the twisted sector in this theory
allows us to calculate the vacuum expectation values of exponential fields of the sine-Gordon theory in first order over Massive Thirring
Models coupling constant. It appears that the apparent difficulty in radial
quantization of massive theories, namely the explicite ''time'' dependence of
the Hamiltonian, may be successfully overcome. The result we have obtained
agrees with the exact formula conjectured by Lukyanov and Zamolodchikov and
coincides with the analogous calculations recently carried out in dual angular
quantization approach by one of the authors.Comment: 16 pages, no figures, LaTe
A randomised controlled trial of mentalization-based treatment versus structured clinical management for patients with comorbid borderline personality disorder and antisocial personality disorder.
BACKGROUND: Antisocial personality disorder (ASPD) is an under-researched mental disorder. Systematic reviews and policy documents identify ASPD as a priority area for further treatment research because of the scarcity of available evidence to guide clinicians and policymakers; no intervention has been established as the treatment of choice for this disorder. Mentalization-based treatment (MBT) is a psychotherapeutic treatment which specifically targets the ability to recognise and understand the mental states of oneself and others, an ability shown to be compromised in people with ASPD. The aim of the study discussed in this paper is to investigate whether MBT can be an effective treatment for alleviating symptoms of ASPD. METHODS: This paper reports on a sub-sample of patients from a randomised controlled trial of individuals recruited for treatment of suicidality, self-harm, and borderline personality disorder. The study investigates whether outpatients with comorbid borderline personality disorder and ASPD receiving MBT were more likely to show improvements in symptoms related to aggression than those offered a structured protocol of similar intensity but excluding MBT components. RESULTS: The study found benefits from MBT for ASPD-associated behaviours in patients with comorbid BPD and ASPD, including the reduction of anger, hostility, paranoia, and frequency of self-harm and suicide attempts, as well as the improvement of negative mood, general psychiatric symptoms, interpersonal problems, and social adjustment. CONCLUSIONS: MBT appears to be a potential treatment of consideration for ASPD in terms of relatively high level of acceptability and promising treatment effects. TRIAL REGISTRATION: ISRCTN ISRCTN27660668 , Retrospectively registered 21 October 2008
High accuracy binary black hole simulations with an extended wave zone
We present results from a new code for binary black hole evolutions using the
moving-puncture approach, implementing finite differences in generalised
coordinates, and allowing the spacetime to be covered with multiple
communicating non-singular coordinate patches. Here we consider a regular
Cartesian near zone, with adapted spherical grids covering the wave zone. The
efficiencies resulting from the use of adapted coordinates allow us to maintain
sufficient grid resolution to an artificial outer boundary location which is
causally disconnected from the measurement. For the well-studied test-case of
the inspiral of an equal-mass non-spinning binary (evolved for more than 8
orbits before merger), we determine the phase and amplitude to numerical
accuracies better than 0.010% and 0.090% during inspiral, respectively, and
0.003% and 0.153% during merger. The waveforms, including the resolved higher
harmonics, are convergent and can be consistently extrapolated to
throughout the simulation, including the merger and ringdown. Ringdown
frequencies for these modes (to ) match perturbative
calculations to within 0.01%, providing a strong confirmation that the remnant
settles to a Kerr black hole with irreducible mass and spin $S_f/M_f^2 = 0.686923 \pm 10\times10^{-6}
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