85 research outputs found
Collective Coordinates and the Absence of Yukawa Coupling in the Classical Skyrme Model
In systems with constraints, physical states must be annihilated by the
constraints. We make use of this rule to construct physical asymptotic states
in the Skyrme model. The standard derivation of the Born terms with asymptotic
physical states shows that there is no Yukawa coupling for the Skyrmion. We
propose a remedy tested in other solitonic models: A Wilsonian action obtained
after integrating the energetic mesons and where the Skyrmion is a quantum
state should have a Yukawa coupling.Comment: LATE
The SO(32) Heterotic and Type IIB Membranes
A two dimensional anomaly cancellation argument is used to construct the
SO(32) heterotic and type IIB membranes. By imposing different boundary
conditions at the two boundaries of a membrane, we shift all of the two
dimensional anomaly to one of the boundaries. The topology of these membranes
is that of a 2-dimensional cone propagating in the 11-dimensional target space.
Dimensional reduction of these membranes yields the SO(32) heterotic and type
IIB strings.Comment: 12 pages, Late
0,2 string compactifications: the Higgs mechanism
We present the Higgs mechanism in (0,2) compactifications. The existence of a vector bundle data duality (VBDD) in (0,2) compactifications which is present at the Landau-Ginzburg point allows us to connect in a smooth manner theories with different gauge groups with the same base manifold and same number of effective generations. As we move along the Kahler moduli space of the theories with E_6 gauge group, some of the gauginos pick up masses and break the gauge group to SO(10) or SU(5)
Can Plane Wave Modes be Physical Modes in Soliton Models?
I show that plane waves may not be used as asymptotic states in soliton
models because they describe unphysical states. When asymptotic states are
taken to be physical there is no T-matrix of \cO(1).Comment: Latex. Published in Phys. Lett.
Lagrangian Becchi-Rouet-Stora-Tyutin treatment of collective coordinates
The Becchi-Rouet-Stora-Tyutin (BRST) treatment for the quantization of
collective coordinates is considered in the Lagrangian formalism. The motion of
a particle in a Riemannian manifold is studied in the case when the classical
solutions break a non-abelian global invariance of the action. Collective
coordinates are introduced, and the resulting gauge theory is quantized in the
BRST antifield formalism. The partition function is computed perturbatively to
two-loops, and it is shown that the results are independent of gauge-fixing
parameters.Comment: LaTeX file, 26 pages, PostScript figures at end of fil
Four-particle condensate in strongly coupled fermion systems
Four-particle correlations in fermion systems at finite temperatures are
investigated with special attention to the formation of a condensate. Instead
of the instability of the normal state with respect to the onset of pairing
described by the Gorkov equation, a new equation is obtained which describes
the onset of quartetting. Within a model calculation for symmetric nuclear
matter, we find that below a critical density, the four-particle condensation
(alpha-like quartetting) is favored over deuteron condensation (triplet
pairing). This pairing-quartetting competition is expected to be a general
feature of interacting fermion systems, such as the excition-biexciton system
in excited semiconductors. Possible experimental consequences are pointed out.Comment: LaTeX, 11 pages, 2 figures, uses psfig.sty (included), to be
published in Phys. Rev. Lett., tentatively scheduled for 13 April 1998
(Volume 80, Number 15
Need and importance of health protection training in Nepal
By investing in health protection, the health of the nation can be safeguarded from future threats of uncontrolled infectious disease epidemics and disasters
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