2,340 research outputs found
On computation of the first Baues--Wirsching cohomology of a freely-generated small category
The Baues--Wirsching cohomology is one of the cohomologies of a small
category. Our aim is to describe the first Baues--Wirsching cohomology of the
small category generated by a finite quiver freely. We consider the case where
the coefficient is a natural system obtained by the composition of a functor
and the target functor. We give an algorithm to obtain generators of the vector
space of inner derivations. It is known that there exists a surjection from the
vector space of derivations of the small category to the first Baues--Wirsching
cohomology whose kernel is the vector space of inner derivations.Comment: 11 page
Conformal Turbulence with Boundary
Based upon the formalism of conformal field theory with a boundary, we give a
description of the boundary effect on fully developed two dimensional
turbulence. Exact one and two point velocity correlation functions and energy
power spectrum confined in the upper half plane are obtained using the image
method. This result enables us to address the infrared problem of the theory of
conformal turbulence.Comment: 10pages, KHTP-93-01, SNUCTP-93-0
Duality in Complex sine-Gordon Theory
New aspects of the complex sine-Gordon theory are addressed through the
reformulation of the theory in terms of the gauged Wess-Zumino-Witten action. A
dual transformation between the theory for the coupling constant \b > 0 and
the theory for \b < 0 is given which agrees with the Krammers-Wannier duality
in the context of perturbed conformal field theory. The B\"{a}cklund transform
and the nonlinear superposition rule for the complex sine-Gordon theory are
presented and from which, exact solutions, solitons and breathers with U(1)
charge, are derived. We clarify topological and nontopological nature of
neutral and charged solitons respectively, and discuss about the duality
between the vector and the axial U(1) charges.Comment: 10 pages, LaTe
Deformed Minimal Models and Generalized Toda Theory
We introduce a generalization of -type Toda theory based on a
non-abelian group G, which we call the -Toda theory, and its affine
extensions in terms of gauged Wess-Zumino-Witten actions with deformation
terms. In particular, the affine -Toda theory describes the
integrable deformation of the minimal conformal theory for the critical Ising
model by the operator . We derive infinite conserved charges and
soliton solutions from the Lax pair of the affine -Toda theory.
Another type of integrable deformation which accounts for the
-deformation of the minimal model is also found in the gauged
Wess-Zumino-Witten context and its infinite conserved charges are given.Comment: 11pages, SNUCTP 94-83 (One reference has been added.
Health utility bias: A meta-analytic evaluation
A common assertion is that rating scale (RS) values are lower than both
standard gamble (SG) and time tradeoff (TTO) values. However, differences among these
methods may be due to method specific bias. While SG and TTO suffer systematic bias, RS
responses are known to depend on the range and frequency of other health states being evaluated.
Over many diverse studies this effect is predicted to diminish. Thus, a systematic review and data
synthesis of RS-TTO and RS-SG difference scores may better reveal persistent dissimilarities.
PURPOSE: To establish through systematic review and meta-analysis the net effect of biases that
endure over many studies of utilities
Classical Matrix sine-Gordon Theory
The matrix sine-Gordon theory, a matrix generalization of the well-known
sine-Gordon theory, is studied. In particular, the -generalization where
fields take value in describes integrable deformations of conformal
field theory corresponding to the coset . Various
classical aspects of the matrix sine-Gordon theory are addressed. We find exact
solutions, solitons and breathers which generalize those of the sine-Gordon
theory with internal degrees of freedom, by applying the Zakharov-Shabat
dressing method and explain their physical properties. Infinite current
conservation laws and the B\"{a}cklund transformation of the theory are
obtained from the zero curvature formalism of the equation of motion. From the
B\"{a}cklund transformation, we also derive exact solutions as well as a
nonlinear superposition principle by making use of the Bianchi's permutability
theorem.Comment: 25 pages, 6 Postscript figure
Design and fabrication of double pancake coil using 2G wire for conduction cooled superconducting magnet
AbstractA large bore double pancake coil(DPC) was designed and tested with 2G HTS wire to develop the conduction cooled superconducting magnet with central field intensity of 3 T at 20K operating temperature and clear bore of 100mm at room temperature. The effect of insulation between turns of double pancake coils was tested. Two double pancake coils with and without turn to turn insulation were wound using 4mm wide 2G conductor. A temporary result suggests that the coil wound without electrical insulation can be protected from higher over current and shows improved stability
Path Integral Bosonization of Massive GNO Fermions
We show the quantum equivalence between certain symmetric space sine-Gordon
models and the massive free fermions. In the massless limit, these fermions
reduce to the free fermions introduced by Goddard, Nahm and Olive (GNO) in
association with symmetric spaces . A path integral formulation is given
in terms of the Wess-Zumino-Witten action where the field variable takes
value in the orthogonal, unitary, and symplectic representations of the group
in the basis of the symmetric space. We show that, for example, such a path
integral bosonization is possible when the symmetric spaces are or . We also address the
relation between massive GNO fermions and the nonabelian solitons, and explain
the restriction imposed on the fermion mass matrix due to the integrability of
the bosonic model.Comment: 11 page
Prospects of mass measurements for neutral MSSM Higgs bosons in the intense-coupling regime at a Linear Collider
We analyze the prospects for detecting the three neutral Higgs bosons of the
Minimal Supersymmetric extension of the Standard Model in the intense-coupling
regime at e+e- colliders. Due to the small mass differences between the Higgs
states in this regime and their relative large total decay widths, the
discrimination between the particles is challenging at the LHC and in some
cases even impossible. We propose to use the missing mass technique in the
Higgs-strahlung process in e+e- collisions to distinguish between the two
CP-even Higgs eigenstates h and H, relying on their b b-bar decay in the
b,b-bar,l+,l- event sample. Ah and AH associated production is then studied in
the 4b-jet event sample to probe the CP-odd A boson. At collider energies
sqrt(s) = 300 GeV and an integrated luminosity of 500 fb-1, accuracies in the
mass measurement of the CP-even Higgs bosons are expected to range from 100 to
300 MeV, while for the CP-odd A boson, accuracies of less than 500 MeV can be
obtained.Comment: 12 pages, 15 Postscript figure
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