352 research outputs found
Hamiltonian lattice gauge theory: wavefunctions on large lattices
We discuss an algorithm for the approximate solution of Schrodinger's
equation for lattice gauge theory, using lattice SU(3) as an example. A basis
is generated by repeatedly applying an effective Hamiltonian to a ``starting
state.'' The resulting basis has a cluster decomposition and long-range
correlations. One such basis has about 10^4 states on a 10X10X10 lattice. The
Hamiltonian matrix on the basis is sparse, and the elements can be calculated
rapidly. The lowest eigenstates of the system are readily calculable.Comment: 4 pages, (contribution to Lattice'92 conference); requires
espcrc2.st
A Gauge-fixed Hamiltonian for Lattice QCD
We study the gauge fixing of lattice QCD in 2+1 dimensions, in the
Hamiltonian formulation. The technique easily generalizes to other theories and
dimensions. The Hamiltonian is rewritten in terms of variables which are gauge
invariant except under a single global transformation. This paper extends
previous work, involving only pure gauge theories, to include matter fields.Comment: 7 pages of LaTeX, RU-92-45 and BUHEP-92-3
Regge Trajectories with Square-Root Branch Points and Their Regge Cuts
We discuss branch points in the complex angular momentum plane formed by two Regge poles on trajectories with square-root branch points at t=0. We find several new cuts which collide with the expected Mandelstam cuts at t=0. In the bootstrap of the Pomeranchon pole, the collection of cuts has the same effect as in the case of linear trajectories: The Pomeranchon can have α(0)=1 only if certain couplings vanish at t=0
Modified WKB approximation
In the WKB approximation the \nabla^2S term in Schrodinger's equation is subordinate to the |\nabla S|^2 term. Here we study an anti-WKB approximation in which the \nabla^2 S term dominates (after a guess for S is supplied). Our approximation produces only the nodeless ground state wavefunction, but it can be used in potential problems where the potential is not symmetric, and in problems where there are many degrees of freedom. As a test, we apply the method to potential problems, including the hydrogen and helium atoms and to \phi^4 field theory.In the WKB approximation the term in Schrodinger's equation is subordinate to the |\nabla S|~2 term. Here we study an anti-WKB approximation in which the term dominates (after a guess for S is supplied). Our approximation produces only the nodeless ground state wavefunction, but it can be used in potential problems where the potential is not symmetric, and in problems where there are many degrees of freedom. As a test, we apply the method to potential problems, including the hydrogen and helium atoms and to field theory.In the WKB approximation the term in Schrodinger's equation is subordinate to the |\nabla S|^2 term. Here we study an anti-WKB approximation in which the term dominates (after a guess for S is supplied). Our approximation produces only the nodeless ground state wavefunction, but it can be used in potential problems where the potential is not symmetric, and in problems where there are many degrees of freedom. As a test, we apply the method to potential problems, including the hydrogen and helium atoms and to field theory
Peripheral parasite density and its relationship to severity of disease in pediatric cerebral malaria
Synthesis and Characterization of Cobalt(II), Nickel(II) and Copper(II) Chloride Complexes with Bis[(diphenylphosphinyl)methyl] phenylphosphine Oxide and Bis[(diphenylphosphinyl)methyl]phosphinic Acid
A series of cobalt(II), nickel(II) and copper(II) chloride complexes
with the tripode organophosphorous compounds: bis[(diphenylphosphinyl)
methyl]phenylphosphine oxide (RPPh) and bis
[(diphenylphosphinyl)methyl]phosphinic acid (RPOH) were studied.
Complexes of the general stoichiometry [M(RPPh)s] [MC14] • 4H20
and fM(RPOH)Cl · nH20]m (M = Co(II), Ni(II) or Cu(II); n = 0 - 4,
m = 1, 2 or more) were isolated.
According to spectral and magnetic data, complexes with the
RPPh ligand appear to have both an octahedral and a tetrahedral
surrounding of the metal(II) ion.
For the complexes [M(RPOH)Cl · nH20]m the electronic effect
of the metal ion seems to be predominant. A tetrahedra<! surrounding
for the cobalt(II) complex, an octahedral surrounding for
the nickel(II) complex and a tetragonal distorted octahedral surrounding
for the copper(II) complex has to be assumed
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