1,120 research outputs found
Open String on Symmetric Product
We develop some basic properties of the open string on the symmetric product
which is supposed to describe the open string field theory in discrete
lightcone quantization (DLCQ). After preparing the consistency conditions of
the twisted boundary conditions for Annulus/M\"obius/Klein Bottle amplitudes in
generic non-abelian orbifold, we classify the most general solutions of the
constraints when the discrete group is . We calculate the corresponding
orbifold amplitudes from two viewpoints -- from the boundary state formalism
and from the trace over the open string Hilbert space. It is shown that the
topology of the world sheet for the short string and that of the long string in
general do not coincide. For example the annulus sector for the short string
contains all the sectors (torus, annulus, Klein bottle, M\"obius strip) of the
long strings. The boundary/cross-cap states of the short strings are classified
into three categories in terms of the long string, the ordinary boundary and
the cross-cap states, and the ``joint'' state which describes the connection of
two short strings. We show that the sum of the all possible boundary conditions
is equal to the exponential of the sum of the irreducible amplitude -- one body
amplitude of long open (closed) strings. This is typical structure of DLCQ
partition function. We examined that the tadpole cancellation condition in our
language and derived the well-known gauge group .Comment: 56 pages, 11 figures, Late
Biconformal supergravity and the AdS/CFT conjecture
Biconformal supergravity models provide a new gauging of the superconformal
group relevant to the Maldacena conjecture. Using the group quotient method to
biconformally gauge SU(2,2|N), we generate a 16-dim superspace. We write the
most general even- and odd-parity actions linear in the curvatures, the bosonic
sector of which is known to descend to general relativity on a 4-dim manifold.Comment: 35 pages, adjusted group nomenclature, 1 reference and
acknowledgements adde
Gauge theories of spacetime symmetries
Gauge theories of conformal spacetime symmetries are presented which merge
features of Yang-Mills theory and general relativity in a new way. The models
are local but nonpolynomial in the gauge fields, with a nonpolynomial structure
that can be elegantly written in terms of a metric (or vielbein) composed of
the gauge fields. General relativity itself emerges from the construction as a
gauge theory of spacetime translations. The role of the models within a general
classification of consistent interactions of gauge fields is discussed as well.Comment: 8 pages, revtex; v2: minor improvements of text and formulas; v3:
typo in formula after eq. (35) correcte
Spacetime Fermions in Light-cone Gauge Superstring Field Theory and Dimensional Regularization
We consider the dimensional regularization of the light-cone gauge type II
superstring field theories in the NSR formalism. In the previous work, we have
calculated the tree-level amplitudes with external lines in the (NS,NS) sector
using the regularization and shown that the desired results are obtained
without introducing contact term interactions. In this work, we study the
tree-level amplitudes with external lines in the Ramond sector. In order to
deal with them, we propose a worldsheet theory to be used instead of that for
the naive dimensional regularization. With the worldsheet theory, we regularize
and define the tree-level amplitudes by analytic continuation. We show that the
results coincide with those of the first quantized formulation.Comment: 28 pages, 5 figures; v2: more details of our manipulations in
subsection 3.2 added, figures and references added; v3: clarifications adde
Effective potential analysis for 5D SU(2) gauge theories at finite temperature and radius
We calculate the one loop effective potential for a 5D SU(2) gauge field
theory at finite temperature and radius R=1/M. This calculation is
performed, for the first time, in the case of background fields with two
constant components (directed towards the compact extra dimension
with radius R) and (directed towards the compact Euclidean time
with radius ). This model possesses two discrete symmetries known as
Z_{M}(2) and Z_{T}(2). The corresponding phase diagram is presented in Ref. 4.
However the arguments which lead to this diagram are mainly qualitative. We
present a detailed analysis, from our point of view, for this phase diagram,
and we support our arguments performing lattice simulations for a simple
phenomenological model with two scalar fields interacting through the
previously calculated potential.Comment: 18 pages, 7 figures ; typos correcte
Digestive organs: Carcinoma of the gallbladder and extrahepatic bile ducts
Review on Digestive organs: Carcinoma of the gallbladder and extrahepatic bile ducts, with data on clinics, and the genes involved
SUSY flavor structure of generic 5D supergravity models
We perform a comprehensive and systematic analysis of the SUSY flavor
structure of generic 5D supergravity models on with multiple
-odd vector multiplets that generate multiple moduli. The SUSY flavor
problem can be avoided due to contact terms in the 4D effective K\"ahler
potential peculiar to the multi-moduli case. A detailed phenomenological
analysis is provided based on an illustrative model.Comment: 37 pages, 7 figures, Sec.4 is modifie
Gravitational coupling to two-particle bound states and momentum conservation in deep inelastic scattering
The momentum conservation sum rule for deep inelastic scattering (DIS) from
composite particles is investigated using the general theory of relativity. For
two 1+1 dimensional examples, it shown that covariant theories automatically
satisy the DIS momentum conservation sum rule provided the bound state is
covariantilly normalized. Therefore, in these cases the two DIS sum rules for
baryon conservation and momentum conservation are equivalent
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