66 research outputs found
Two-dimensional super Yang-Mills theory investigated with improved resolution
In earlier work, N=(1,1) super Yang--Mills theory in two dimensions was found
to have several interesting properties, though these properties could not be
investigated in any detail. In this paper we analyze two of these properties.
First, we investigate the spectrum of the theory. We calculate the masses of
the low-lying states using the supersymmetric discrete light-cone (SDLCQ)
approximation and obtain their continuum values. The spectrum exhibits an
interesting distribution of masses, which we discuss along with a toy model for
this pattern. We also discuss how the average number of partons grows in the
bound states. Second, we determine the number of fermions and bosons in the
N=(1,1) and N=(2,2) theories in each symmetry sector as a function of the
resolution. Our finding that the numbers of fermions and bosons in each sector
are the same is part of the answer to the question of why the SDLCQ
approximation exactly preserves supersymmetry.Comment: 20 pages, 10 figures, LaTe
Modal expansions and non-perturbative quantum field theory in Minkowski space
We introduce a spectral approach to non-perturbative field theory within the
periodic field formalism. As an example we calculate the real and imaginary
parts of the propagator in 1+1 dimensional phi^4 theory, identifying both
one-particle and multi-particle contributions. We discuss the computational
limits of existing diagonalization algorithms and suggest new quasi-sparse
eigenvector methods to handle very large Fock spaces and higher dimensional
field theories.Comment: new material added, 12 pages, 6 figure
Improved results for N=(2,2) super Yang-Mills theory using supersymmetric discrete light-cone quantization
We consider the (1+1)-dimensional super Yang--Mills theory
which is obtained by dimensionally reducing super Yang--Mills
theory in four dimension to two dimensions. We do our calculations in the
large- approximation using Supersymmetric Discrete Light Cone
Quantization. The objective is to calculate quantities that might be
investigated by researchers using other numerical methods. We present a
precision study of the low-mass spectrum and the stress-energy correlator
. We find that the mass gap of this theory closes as the
numerical resolution goes to infinity and that the correlator in the
intermediate region behaves like .Comment: 18 pages, 8 figure
Assessing childhood maltreatment and mental health correlates of disordered eating profiles in a nationally representative sample of English females
PURPOSE: Previous research suggests that childhood maltreatment is associated with the onset of eating disorders (ED). In turn, EDs are associated with alternative psychopathologies such as depression and posttraumatic stress disorder (PTSD), and with suicidality. Moreover, it has been reported that various ED profiles may exist. The aim of the current study was to examine the profiles of disordered eating and the associations of these with childhood maltreatment and with mental health psychopathology. METHODS: The current study utilised a representative sample of English females (N = 4206) and assessed for the presence of disordered eating profiles using Latent Class Analysis. Multinomial logistic regression was implemented to examine the associations of childhood sexual and physical abuse with the disordered eating profiles and the associations of these with PTSD, depression and suicidality. RESULTS: Results supported those of previous findings in that we found five latent classes of which three were regarded as disordered eating classes. Significant relationships were found between these and measures of childhood trauma and mental health outcomes. CONCLUSIONS: Childhood sexual and physical abuse increased the likelihood of membership in disordered eating classes and these in turn increased the likelihood of adverse mental health and suicidal outcomes
The linearized pressure Poisson equation for global instability analysis of incompressible flows
Identification of different <em>ALK</em> mutations in a pair of neuroblastoma cell lines established at diagnosis and relapse
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