2,209 research outputs found
Tensor Spectra Templates for Axion-Gauge Fields Dynamics during Inflation
gauge fields can generate large gravitational waves during inflation,
if they are coupled to an axion which can be either the inflaton or a spectator
field. The shape of the produced tensor power spectrum depends
on the form of the axion potential. We derive analytic expressions and provide
general templates for for various types of the spectator axion
potential. Furthermore, we explore the detectability of the oscillatory
feature, which is present in in the case of an axion monodromy
model, by possible future CMB B-mode polarization observations.Comment: 31 pages, 11 figure
Gravitational Effects of Quantum Fields in the Interior of a Cylindrical Black Hole
The gravitational back-reaction is calculated for the conformally invariant
scalar field within a black cosmic string interior with cosmological constant.
Using the perturbed metric, the gravitational effects of the quantum field are
calculated. It is found that the perturbations initially strengthen the
singularity. This effect is similar to the case of spherical symmetry (without
cosmological constant). This indicates that the behaviour of quantum effects
may be universal and not dependent on the geometry of the spacetime nor the
presence of a non-zero cosmological constant.Comment: 13 pages, 1 figure, uses AMS package. D.E. solution corrected. Some
qualitative results are change
Free Boson Representation of
A representation of the quantum affine algebra of an
arbitrary level is constructed in the Fock module of eight boson fields.
This realization reduces the Wakimoto representation in the
limit. The analogues of the screening currents are also obtained. They commute
with the action of modulo total differences of some
fields.Comment: 12 pages, LaTeX, RIMS-920, YITP/K-101
A Quantum Deformation of the Virasoro Algebra and the Macdonald Symmetric Functions
A quantum deformation of the Virasoro algebra is defined. The Kac
determinants at arbitrary levels are conjectured. We construct a bosonic
realization of the quantum deformed Virasoro algebra. Singular vectors are
expressed by the Macdonald symmetric functions. This is proved by constructing
screening currents acting on the bosonic Fock space.Comment: 15 pages, latex fil
Shape of Deconstruction
We construct a six-dimensional Maxwell theory using a latticized extra space,
the continuum limit of which is a shifted torus recently discussed by Dienes.
This toy model exhibits the correspondence between continuum theory and
discrete theory, and give a geometrical insight to theory-space model building.Comment: 10 pages, 2 figures, RevTeX4. a citation adde
Multi-graviton theory, a latticized dimension, and the cosmological constant
Beginning with the Pauli-Fierz theory, we construct a model for
multi-graviton theory. Couplings between gravitons belonging to
nearest-neighbor ``theory spaces'' lead to a discrete mass spectrum. Our model
coincides with the Kaluza-Klein theory whose fifth dimension is latticized.
We evaluate one-loop vacuum energy in models with a circular latticized extra
dimension as well as with compact continuous dimensions. We find that the
vacuum energy can take a positive value, if the dimension of the continuous
space time is . Moreover, since the amount of the vacuum energy can
be an arbitrary small value according to the choice of parameters in the model,
our models is useful to explain the small positive dark energy in the present
universe.Comment: 10 pages, No figure. Needs REVTeX4. citations are corrected and minor
correction
Impurity Operators in RSOS Models
We give a construction of impurity operators in the `algebraic analysis'
picture of RSOS models. Physically, these operators are half-infinite
insertions of certain fusion-RSOS Boltzmann weights. They are the face analogue
of insertions of higher spin lines in vertex models. Mathematically, they are
given in terms of intertwiners of modules. We present a
detailed perturbation theory check of the conjectural correspondence between
the physical and mathematical constructions in a particular simple example.Comment: Latex, 24 pages, uses amsmath, amsthm, amssymb, epic, eepic and
texdraw style files (Minor typos corrected) (minor changes
Bulk Fermion Stars with New Dimensions
Many efforts have been devoted to the studies of the phenomenology in
particle physics with extra dimensions. We propose degenerate fermion stars
with extra dimensions and study what features characterized by the size of
extra dimensions should appear in its structure. We find that Kaluza-Klein
excited modes arise for the larger scale of extra dimensions and examine the
conditions on which different layers should be caused in the inside of the
stars. We expound how the extra dimensions affect on physical quantities.Comment: 20 pages, 14 figure
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