5,595 research outputs found
General Analysis of Inflation in the Jordan frame Supergravity
We study various inflation models in the Jordan frame supergravity with a
logarithmic Kahler potential. We find that, in a class of inflation models
containing an additional singlet in the superpotential, three types of
inflation can be realized: the Higgs-type inflation, power-law inflation, and
chaotic inflation with/without a running kinetic term. The former two are
possible if the holomorphic function dominates over the non-holomorphic one in
the frame function, while the chaotic inflation occurs when both are
comparable. Interestingly, the fractional-power potential can be realized by
the running kinetic term. We also discuss the implication for the Higgs
inflation in supergravity.Comment: 16 pages, 1 figur
Orbital Compass Model as an Itinerant Electron System
Two-dimensional orbital compass model is studied as an interacting itinerant
electron model. A Hubbard-type tight-binding model, from which the orbital
compass model is derived in the strong coupling limit, is identified. This
model is analyzed by the random-phase approximation (RPA) and the
self-consistent RPA methods from the weak coupling. Anisotropy for the orbital
fluctuation in the momentum space is qualitatively changed by the on-site
Coulomb interaction. This result is explained by the fact that the dominant
fluctuation is changed from the intra-band nesting to the inter-band one by
increasing the interaction.Comment: 7 pages, 8 figure
Higgs Chaotic Inflation in Standard Model and NMSSM
We construct a chaotic inflation model in which the Higgs fields play the
role of the inflaton in the standard model as well as in the singlet extension
of the supersymmetric standard model. The key idea is to allow a non-canonical
kinetic term for the Higgs field. The model is a realization of the recently
proposed running kinetic inflation, in which the coefficient of the kinetic
term grows as the inflaton field. The inflaton potential depends on the
structure of the Higgs kinetic term. For instance, the inflaton potential is
proportional to phi^2 and phi^{2/3} in the standard model and NMSSM,
respectively. It is also possible to have a flatter inflaton potential.Comment: 5 pages. v2:discussion and references adde
Using Superconducting Qubit Circuits to Engineer Exotic Lattice Systems
We propose an architecture based on superconducting qubits and resonators for
the implementation of a variety of exotic lattice systems, such as spin and
Hubbard models in higher or fractal dimensions and higher-genus topologies.
Spin systems are realized naturally using qubits, while superconducting
resonators can be used for the realization of Bose-Hubbard models. Fundamental
requirements for these designs, such as controllable interactions between
arbitrary qubit pairs, have recently been implemented in the laboratory,
rendering our proposals feasible with current technology.Comment: 7 pages (two-column), 3 figure
Holographic Renormalization of Foliation Preserving Gravity and Trace Anomaly
From the holographic renormalizationg group viewpoint, while the scale
transformation plays a primary role in the duality by providing the extra
dimension, the special conformal transformation seems to only play a secondary
role. We, however, claim that the space-time diffeomorphism is crucially
related to the latter. For its demonstration, we study the holographic
renormalization group flow of a foliation preserving diffeomophic theory of
gravity (a.k.a. space-time flipped Horava gravity). We find that the dual field
theory, if any, is only scale invariant but not conformal invariant. In
particular, we show that the holographic trace anomaly in four-dimension
predicts the Ricci scalar squared term that would be incompatible with the
Wess-Zumino consistency condition if it were conformal. This illustrates how
the foliation preserving diffeomophic theory of gravity could be inconsistent
with a theorem of the dual unitary quantum field theory.Comment: 18 pages, v2: reference added, v3: comments on more recent literature
added in response to referee's reques
Degenerate dispersive equations arising in the study of magma dynamics
An outstanding problem in Earth science is understanding the method of
transport of magma in the Earth's mantle. Models for this process, transport in
a viscously deformable porous media, give rise to scalar degenerate,
dispersive, nonlinear wave equations. We establish a general local
well-posedness for a physical class of data (roughly ) via fixed point
methods. The strategy requires positive lower bounds on the solution. This is
extended to global existence for a subset of possible nonlinearities by making
use of certain conservation laws associated with the equations. Furthermore, we
construct a Lyapunov energy functional, which is locally convex about the
uniform state, and prove (global in time) nonlinear dynamic stability of the
uniform state for any choice of nonlinearity. We compare the dynamics to that
of other problems and discuss open questions concerning a larger range of
nonlinearities, for which we conjecture global existence.Comment: 27 Pages, 7 figures are not present in this version. See
http://www.columbia.edu/~grs2103/ for a PDF with figures. Submitted to
Nonlinearit
Empirical Determination of Threshold Partial Wave Amplitudes in
Using the model independent irreducible tensor approach to
production in collisions, we show theoretically that, it is advantageous
to measure experimentally the polarization of , in addition to the
proposed experimental study employing a polarized beam and a polarized target.Comment: 6 pages, 1 Table, Latex-2
Observables and Correlators in Nonrelativistic ABJM Theory
Non-relativistic ABJM theory is defined by Galilean limit of mass-deformed
N=6 Chern-Simons theory. Holographic string theory dual to the theory is not
known yet. To understand features candidate gravity dual might exhibit, we
examine local and nonlocal physical observables and their correlations in the
non-relativistic ABJM theory. We show that gauge invariant local observables
correspond to zero-norm states and that correlation functions among them are
trivial. We also show that a particular class of nonlocal observables, Wilson
loops, are topological in the sense that their correlation functions coincide
with those of pure Chern-Simons theory. We argue that the theory is
nevertheless physical and illustrate several physical observables whose
correlation functions are nontrivial. We also study quantum aspects. We show
that Chern-Simons level is finitely renormalized and that dilatation operator
acting on spin chain is trivial at planar limit. These results all point to
string scale geometry of gravity dual and to intriguing topological and
tensionless nature of dual string defined on it.Comment: 1+30 pages, no figure, v2. typos fixed and references adde
Omega Production in pp Collisions
A model-independent irreducible tensor formalism which has been developed
earlier to analyze measurements of , is
extended to present a theoretical discussion of
and the polarization of in . The recent
measurement of unpolarized differential cross section for is
analyzed using this theoretical formalism.Comment: 5 pages (double column), no figures, uses revtex
Secular instability in quasi-viscous disc accretion
A first-order correction in the -viscosity parameter of Shakura and
Sunyaev has been introduced in the standard inviscid and thin accretion disc. A
linearised time-dependent perturbative study of the stationary solutions of
this "quasi-viscous" disc leads to the development of a secular instability on
large spatial scales. This qualitative feature is equally manifest for two
different types of perturbative treatment -- a standing wave on subsonic
scales, as well as a radially propagating wave. Stability of the flow is
restored when viscosity disappears.Comment: 15 pages, 2 figures, AASTeX. Added some new material and upgraded the
reference lis
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