17,485 research outputs found
Meta-Stable Brane Configurations by Adding an Orientifold-Plane to Giveon-Kutasov
In hep-th/0703135, they have found the type IIA intersecting brane
configuration where there exist three NS5-branes, D4-branes and anti-D4-branes.
By analyzing the gravitational interaction for the D4-branes in the background
of the NS5-branes, the phase structures in different regions of the parameter
space were studied in the context of classical string theory. In this paper, by
adding the orientifold 4-plane and 6-plane to the above brane configuration, we
describe the intersecting brane configurations of type IIA string theory
corresponding to the meta-stable nonsupersymmetric vacua of these gauge
theories.Comment: 21 pp, 6 figures; reduced bytes of figures, DBI action analysis added
and to appear in JHE
Time-convolutionless reduced-density-operator theory of a noisy quantum channel: a two-bit quantum gate for quantum information processing
An exact reduced-density-operator for the output quantum states in
time-convolutionless form was derived by solving the quantum Liouville equation
which governs the dynamics of a noisy quantum channel by using a projection
operator method and both advanced and retarded propagators in time. The
formalism developed in this work is general enough to model a noisy quantum
channel provided specific forms of the Hamiltonians for the system, reservoir,
and the mutual interaction between the system and the reservoir are given.
Then, we apply the formulation to model a two-bit quantum gate composed of
coupled spin systems in which the Heisenberg coupling is controlled by the
tunneling barrier between neighboring quantum dots. Gate Characteristics
including the entropy, fidelity, and purity are calculated numerically for both
mixed and entangled initial states
More on Meta-Stable Brane Configuration
We describe the intersecting brane configuration of type IIA string theory
corresponding to the meta-stable nonsupersymmetric vacua in four dimensional
N=1 supersymmetric SU(N_c) gauge theory with an antisymmetric flavor, a
conjugate symmetric flavor, eight fundamental flavors, m_f fundamental flavors
and m_f antifundamental flavors. This is done by analyzing the N=1
supersymmetric SU(2m_f-N_c+4) magnetic gauge theory with dual matters and the
corresponding dual superpotential.Comment: 20 pp, 3 figures; Pages 11,12, and 14 improved; to appear in CQ
Meta-Stable Brane Configurations with Seven NS5-Branes
We present the intersecting brane configurations consisting of NS-branes,
D4-branes(and anti D4-branes) and O6-plane, of type IIA string theory
corresponding to the meta-stable nonsupersymmetric vacua in four dimensional
N=1 supersymmetric SU(N_c) x SU(N_c') x SU(N_c'') gauge theory with a symmetric
tensor field, a conjugate symmetric tensor field and bifundamental fields. We
also describe the intersecting brane configurations of type IIA string theory
corresponding to the nonsupersymmetric meta-stable vacua in the above gauge
theory with an antisymmetric tensor field, a conjugate symmetric tensor field,
eight fundamental flavors and bifundamentals. These brane configurations
consist of NS-branes, D4-branes(and anti D4-branes), D6-branes and O6-planes.Comment: 34pp, 9 figures; Improved the draft and added some footnotes; Figure
1, footnote 7 and captions of Figures 7,8,9 added or improved and to appear
in CQ
Twist and teleportation analogy of the black hole final state
Mathematical connection between the quantum teleportation, the most unique
feature of quantum information processing, and the black hole final state is
studied taking into account the non trivial spacetime geometry. We use the
twist operatation for the generalized entanglement measurement and the final
state boundary conditions to obtain transfer theorems for the black hole
evaporation. This would enable us to put together the universal quantum
teleportation and the black hole evaporation in the unified mathematical
footing. For a renormalized post selected final state of outgoing Hawking
radiation, we found that the measure of mixedness is preserved only in the
special case of final-state boundary condition in the micro-canonical form,
which resmebles perfect teleportation channel.Comment: version_
Sublinear Estimation of Weighted Matchings in Dynamic Data Streams
This paper presents an algorithm for estimating the weight of a maximum
weighted matching by augmenting any estimation routine for the size of an
unweighted matching. The algorithm is implementable in any streaming model
including dynamic graph streams. We also give the first constant estimation for
the maximum matching size in a dynamic graph stream for planar graphs (or any
graph with bounded arboricity) using space which also
extends to weighted matching. Using previous results by Kapralov, Khanna, and
Sudan (2014) we obtain a approximation for general graphs
using space in random order streams, respectively. In
addition, we give a space lower bound of for any
randomized algorithm estimating the size of a maximum matching up to a
factor for adversarial streams
Meta-Stable Brane Configurations of Triple Product Gauge Groups
From an N=1 supersymmetric electric gauge theory with the gauge group SU(N_c)
x SU(N_c') x SU(N_c'') with fundamentals for each gauge group and the
bifundamentals, we apply Seiberg dual to each gauge group and obtain the N=1
supersymmetric dual magnetic gauge theories with dual matters including the
additional gauge singlets. By analyzing the F-term equations of the dual
magnetic superpotentials, we describe the intersecting brane configurations of
type IIA string theory corresponding to the meta-stable nonsupersymmetric vacua
of this gauge theory. We apply also to the case for N=1 supersymmetric electric
gauge theory with the gauge group Sp(N_c) x SO(2N_c') x Sp(N_c'') with flavors
for each gauge group and the bifundamentals. Finally, we describe the
meta-stable brane configurations of multiple product gauge groups.Comment: 80pp, 10 figures; shorten the draft and to appear in IJMP
More on N=1 Matrix Model Curve for Arbitrary N
Using both the matrix model prescription and the strong-coupling approach, we
describe the intersections of n=0 and n=1 non-degenerated branches for quartic
(polynomial of adjoint matter) tree-level superpotential in N=1 supersymmetric
SO(N)/USp(2N) gauge theories with massless flavors. We also apply the method to
the degenerated branch. The general matrix model curve on the two cases we
obtain is valid for arbitrary N and extends the previous work from
strong-coupling approach. For SO(N) gauge theory with equal massive flavors, we
also obtain the matrix model curve on the degenerated branch for arbitrary N.
Finally we discuss on the intersections of n=0 and n=1 non-degenerated branches
for equal massive flavors.Comment: 36pp; to appear in JHE
Nonzero and Neutrino Masses from Modified Neutrino Mixing Matrix
The nonzero and relatively large have been reported by Daya
Bay, T2K, MINOS, and Double Chooz Collaborations. In order to accommodate the
nonzero , we modified the tribimaximal (TB), bimaxima (BM), and
democratic (DC) neutrino mixing matrices. From three modified neutrino mixing
matrices, two of them (the modified BM and DC mixing matrices) can give nonzero
which is compatible with the result of the Daya Bay and T2K
experiments. The modified TB neutrino mixing matrix predicts the value of
greater than the upper bound value of the latest experimental
results. By using the modified neutrino mixing matrices and impose an
additional assumption that neutrino mass matrices have two zeros texture, we
then obtain the neutrino mass in normal hierarchy when
for the neutrino mass matrix from the
modified TB neutrino mixing matrix and for
the neutrino mass matrix from the modified DC neutrino mixing matrix. For these
two patterns of neutrino mass matrices, either the atmospheric mass squared
difference or the solar mass squared difference can be obtained, but not both
of them simultaneously. From four patterns of two zeros texture to be
considered on the obtained neutrino mass matrix from the modified BM neutrino
mixing matrix, none of them can predict correctly neutrino mass spectrum
(normal or inverted hierarchy).Comment: 13 pages, no figure, some references added, and slight revision due
to reviewer(s) comments, to be published in IJMP
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