23,203 research outputs found
QCD Sum Rules and the Determination of Leading Twist Non-Singlet Operator Matrix Elements
We use QCD sum rules to determine directly the leading-twist non-singlet
operator matrix elements based on calculations of three-point correlator
functions in configuration space. We find a different result from that obtained
by integrating the structure functions' expressions obtained by Belyaev and
Ioffe based on calculations of four-point correlators in momentum space. The
origin of this discrepancy remains unclear.Comment: 9 pages, 5 figure
Rigid supersymmetry with boundaries
We construct rigidly supersymmetric bulk-plus-boundary actions, both in
-space and in superspace. For each standard supersymmetric bulk action a
minimal supersymmetric bulk-plus-boundary action follows from an extended -
or -term formula. Additional separately supersymmetric boundary actions can
be systematically constructed using co-dimension one multiplets (boundary
superfields). We also discuss the orbit of boundary conditions which follow
from the Euler-Lagrange variational principle.Comment: 28 pages, JHEP clas
Delta-Isobar Magnetic Form Factor in QCD
We consider the QCD sum rules approach for Delta-isobar magnetic form factor
in the infra-red region . The QCD sum rules in external variable
field are used. The obtained formfactor is in agreement with quark model
predictions for the Delta-isobar magnetic moment.Comment: 13 pages, CEBAF-TH-93-02, Latex, 1 Figur
Cumulant Expansion and Monthly Sum Derivative
Cumulant expansion is used to derive accurate closed-form approximation for
Monthly Sum Options in case of constant volatility model. Payoff of Monthly Sum
Option is based on sum of caped (and probably floored) returns. It is
noticed, that can be used as a small parameter in Edgeworth
expansion. First two leading terms of this expansion are calculated here. It is
shown that the suggest closed-form approximation is in a good agreement with
numerical results for typical mode parameters.Comment: 8 pages, 2 figure
Massless Fermions on the Lattice
We consider a nonlocal lattice action for fermions fermion doubling in
lattice theories. It is shown, that it is possible to avoid the fermionic
doubling in the case of free fermions, but this approach does not reproduce
results for the effective action for gauge fields in the continuum theory,
because the high frequency fermion modes have a strong dependence on the gauge
field.Comment: 16 pages, LATEX, 1 Figure (uuencoded PS-file is attached to the end
of the LATEX file
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