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A determinant of Stirling cycle numbers counts unlabeled acyclic
single-source automata | We show that a determinant of Stirling cycle numbers counts unlabeled acyclic
single-source automata. The proof involves a bijection from these automata to
certain marked lattice paths and a sign-reversing involution to evaluate the
determinant.
|
From dyadic $\Lambda_{\alpha}$ to $\Lambda_{\alpha}$ | In this paper we show how to compute the $\Lambda_{\alpha}$ norm, $\alpha\ge
0$, using the dyadic grid. This result is a consequence of the description of
the Hardy spaces $H^p(R^N)$ in terms of dyadic and special atoms.
|
Computing genus 2 Hilbert-Siegel modular forms over $\Q(\sqrt{5})$ via
the Jacquet-Langlands correspondence | In this paper we present an algorithm for computing Hecke eigensystems of
Hilbert-Siegel cusp forms over real quadratic fields of narrow class number
one. We give some illustrative examples using the quadratic field
$\Q(\sqrt{5})$. In those examples, we identify Hilbert-Siegel eigenforms that
are possible lifts from Hilbert eigenforms.
|
Iterated integral and the loop product | In this article we discuss a relation between the string topology and
differential forms based on the theory of Chen's iterated integrals and the
cyclic bar complex.
|
Fermionic superstring loop amplitudes in the pure spinor formalism | The pure spinor formulation of the ten-dimensional superstring leads to
manifestly supersymmetric loop amplitudes, expressed as integrals in pure
spinor superspace. This paper explores different methods to evaluate these
integrals and then uses them to calculate the kinematic factors of the one-loop
and two-loop massless four-point amplitudes involving two and four Ramond
states.
|
In quest of a generalized Callias index theorem | We give a prescription for how to compute the Callias index, using as
regulator an exponential function. We find agreement with old results in all
odd dimensions. We show that the problem of computing the dimension of the
moduli space of self-dual strings can be formulated as an index problem in
even-dimensional (loop-)space. We think that the regulator used in this Letter
can be applied to this index problem.
|
Approximation for extinction probability of the contact process based on
the Gr\"obner basis | In this note we give a new method for getting a series of approximations for
the extinction probability of the one-dimensional contact process by using the
Gr\"obner basis.
|
Pfaffians, hafnians and products of real linear functionals | We prove pfaffian and hafnian versions of Lieb's inequalities on determinants
and permanents of positive semi-definite matrices. We use the hafnian
inequality to improve the lower bound of R\'ev\'esz and Sarantopoulos on the
norm of a product of linear functionals on a real Euclidean space (this subject
is sometimes called the `real linear polarization constant' problem).
|
Origin of adaptive mutants: a quantum measurement? | This is a supplement to the paper arXiv:q-bio/0701050, containing the text of
correspondence sent to Nature in 1990.
|
Multilinear function series in conditionally free probability with
amalgamation | As in the cases of freeness and monotonic independence, the notion of
conditional freeness is meaningful when complex-valued states are replaced by
positive conditional expectations. In this framework, the paper presents
several positivity results, a version of the central limit theorem and an
analogue of the conditionally free R-transform constructed by means of
multilinear function series.
|
An algorithm for the classification of smooth Fano polytopes | We present an algorithm that produces the classification list of smooth Fano
d-polytopes for any given d. The input of the algorithm is a single number,
namely the positive integer d. The algorithm has been used to classify smooth
Fano d-polytopes for d<=7. There are 7622 isomorphism classes of smooth Fano
6-polytopes and 72256 isomorphism classes of smooth Fano 7-polytopes.
|
The Hardy-Lorentz Spaces $H^{p,q}(R^n)$ | In this paper we consider the Hardy-Lorentz spaces $H^{p,q}(R^n)$, with
$0<p\le 1$, $0<q\le \infty$. We discuss the atomic decomposition of the
elements in these spaces, their interpolation properties, and the behavior of
singular integrals and other operators acting on them.
|
A Note About the {Ki(z)} Functions | In the article [Petojevic 2006], A. Petojevi\' c verified useful properties
of the $K_{i}(z)$ functions which generalize Kurepa's [Kurepa 1971] left
factorial function. In this note, we present simplified proofs of two of these
results and we answer the open question stated in [Petojevic 2006]. Finally, we
discuss the differential transcendency of the $K_{i}(z)$ functions.
|
Pairwise comparisons of typological profiles (of languages) | No abstract given; compares pairs of languages from World Atlas of Language
Structures.
|
Strong decays of charmed baryons | There has been important experimental progress in the sector of heavy baryons
in the past several years. We study the strong decays of the S-wave, P-wave,
D-wave and radially excited charmed baryons using the $^3P_0$ model. After
comparing the calculated decay pattern and total width with the available data,
we discuss the possible internal structure and quantum numbers of those charmed
baryons observed recently.
|
CP violation in beauty decays | Precision tests of the Kobayashi-Maskawa model of CP violation are discussed,
pointing out possible signatures for other sources of CP violation and for new
flavor-changing operators. The current status of the most accurate tests is
summarized.
|
Universal Forces and the Dark Energy Problem | The Dark Energy problem is forcing us to re-examine our models and our
understanding of relativity and space-time. Here a novel idea of Fundamental
Forces is introduced. This allows us to perceive the General Theory of
Relativity and Einstein's Equation from a new pesrpective. In addition to
providing us with an improved understanding of space and time, it will be shown
how it leads to a resolution of the Dark Energy problem.
|
Linear perturbations of matched spacetimes: the gauge problem and
background symmetries | We present a critical review about the study of linear perturbations of
matched spacetimes including gauge problems. We analyse the freedom introduced
in the perturbed matching by the presence of background symmetries and revisit
the particular case of spherically symmetry in n-dimensions. This analysis
includes settings with boundary layers such as brane world models and shell
cosmologies.
|
Quantum Deformations of Relativistic Symmetries | We discussed quantum deformations of D=4 Lorentz and Poincare algebras. In
the case of Poincare algebra it is shown that almost all classical r-matrices
of S. Zakrzewski classification correspond to twisted deformations of Abelian
and Jordanian types. A part of twists corresponding to the r-matrices of
Zakrzewski classification are given in explicit form.
|
Energy density for chiral lattice fermions with chemical potential | We study a recently proposed formulation of overlap fermions at finite
density. In particular we compute the energy density as a function of the
chemical potential and the temperature. It is shown that overlap fermions with
chemical potential reproduce the correct continuum behavior.
|
Much ado about 248 | In this note we present three representations of a 248-dimensional Lie
algebra, namely the algebra of Lie point symmetries admitted by a system of
five trivial ordinary differential equations each of order forty-four, that
admitted by a system of seven trivial ordinary differential equations each of
order twenty-eight and that admitted by one trivial ordinary differential
equation of order two hundred and forty-four.
|
Conformal Field Theory and Operator Algebras | We review recent progress in operator algebraic approach to conformal quantum
field theory. Our emphasis is on use of representation theory in classification
theory. This is based on a series of joint works with R. Longo.
|
The birth of string theory | In this contribution we go through the developments that in the years 1968 to
1974 led from the Veneziano model to the bosonic string.
|
Duality and Tameness | We prove a duality theorem for certain graded algebras and show by various
examples different kinds of failure of tameness of local cohomology.
|
Experimental modeling of physical laws | A physical law is represented by the probability distribution of a measured
variable. The probability density is described by measured data using an
estimator whose kernel is the instrument scattering function. The experimental
information and data redundancy are defined in terms of information entropy.
The model cost function, comprised of data redundancy and estimation error, is
minimized by the creation-annihilation process.
|
Reducing SAT to 2-SAT | Description of a polynomial time reduction of SAT to 2-SAT of polynomial
size.
|
On Equivariant Embedding of Hilbert C^* modules | We prove that an arbitrary (not necessarily countably generated) Hilbert
$G$-$\cla$ module on a G-C^* algebra $\cla$ admits an equivariant embedding
into a trivial $G-\cla$ module, provided G is a compact Lie group and its
action on $\cla$ is ergodic.
|
Invariance and the twisted Chern character : a case study | We give details of the proof of the remark made in \cite{G2} that the Chern
characters of the canonical generators on the K homology of the quantum group
$SU_q(2)$ are not invariant under the natural $SU_q(2)$ coaction. Furthermore,
the conjecture made in \cite{G2} about the nontriviality of the twisted Chern
character coming from an odd equivariant spectral triple on $SU_q(2)$ is
settled in the affirmative.
|
Smooth maps with singularities of bounded K-codimensions | We will prove the relative homotopy principle for smooth maps with
singularities of a given {\cal K}-invariant class with a mild condition. We
next study a filtration of the group of homotopy self-equivalences of a given
manifold P by considering singularities of non-negative {\cal K}-codimensions.
|
Stringy Jacobi fields in Morse theory | We consider the variation of the surface spanned by closed strings in a
spacetime manifold. Using the Nambu-Goto string action, we induce the geodesic
surface equation, the geodesic surface deviation equation which yields a Jacobi
field, and we define the index form of a geodesic surface as in the case of
point particles to discuss conjugate strings on the geodesic surface.
|
Proper J-holomorphic discs in Stein domains of dimension 2 | We prove the existence of global Bishop discs in a strictly pseudoconvex
Stein domain in an almost complex manifold of complex dimension 2.
|
Anisotropic thermo-elasticity in 2D -- Part I: A unified approach | In this note we develop tools and techniques for the treatment of anisotropic
thermo-elasticity in two space dimensions. We use a diagonalisation technique
to obtain properties of the characteristic roots of the full symbol of the
system in order to prove $L^p$--$L^q$ decay rates for its solutions.
|
On the total disconnectedness of the quotient Aubry set | In this paper we show that the quotient Aubry set associated to certain
Lagrangians is totally disconnected (i.e., every connected component consists
of a single point). Moreover, we discuss the relation between this problem and
a Morse-Sard type property for (difference of) critical subsolutions of
Hamilton-Jacobi equations.
|
New simple modular Lie superalgebras as generalized prolongs | Over algebraically closed fields of characteristic p>2, prolongations of the
simple finite dimensional Lie algebras and Lie superalgebras with Cartan matrix
are studied for certain simplest gradings of these algebras. Several new simple
Lie superalgebras are discovered, serial and exceptional, including superBrown
and superMelikyan superalgebras. Simple Lie superalgebras with Cartan matrix of
rank 2 are classified.
|
Towards self-consistent definition of instanton liquid parameters | The possibility of self-consistent determination of instanton liquid
parameters is discussed together with the definition of optimal pseudo-particle
configurations and comparing the various pseudo-particle ensembles. The
weakening of repulsive interactions between pseudo-particles is argued and
estimated.
|
Instanton Liquid at Finite Temperature and Chemical Potential of Quarks | Instanton liquid in heated and strongly interacting matter is studied using
the variational principle. The dependence of the instanton liquid density
(gluon condensate) on the temperature and the quark chemical potential is
determined under the assumption that, at finite temperatures, the dominant
contribution is given by an ensemble of calorons. The respective one-loop
effective quark Lagrangian is used.
|
Nonlinear force-free coronal magnetic field extrapolation scheme based
on the direct boundary integral formulation | This paper has been withdrawn by the authors.
|
Very strong and slowly varying magnetic fields as source of axions | The investigation on the production of particles in slowly varying but
extremely intense magnetic field in extended to the case of axions. The
motivation is, as for some previously considered cases, the possibility that
such kind of magnetic field may exist around very compact astrophysical
objects.
|
Bonding of H in O vacancies of ZnO | We investigate the bonding of H in O vacancies of ZnO using density
functional calculations. We find that H is anionic and does not form
multicenter bonds with Zn in this compound.
|
Neutron Skin and Giant Resonances in Nuclei | Some aspects, both experimental and theoretical, of extracting the neutron
skin $\Delta R$ from properties of isovector giant resonances are discussed.
Existing proposals are critically reviewed. The method relying on the energy
difference between the GTR and IAS is shown to lack sensitivity to $\Delta R$.
A simple explanation of the linear relation between the symmetry energy and the
neutron skin is also given.
|
Gamma-ray emitting AGN and GLAST | I describe the different classes of Active Galactic Nuclei (AGN) and the
basic tenets of unified schemes. I then review the properties of the
extragalactic sources detected in the GeV and TeV bands, showing that the vast
majority of them belong to the very rare blazar class. I further discuss the
kind of AGN GLAST is likely to detect, making some predictions going from the
obvious to the likely, all the way to the less probable.
|
Domain Wall Dynamics near a Quantum Critical Point | We study the real-time domain-wall dynamics near a quantum critical point of
the one-dimensional anisotropic ferromagnetic spin 1/2 chain. By numerical
simulation, we find the domain wall is dynamically stable in the
Heisenberg-Ising model. Near the quantum critical point, the width of the
domain wall diverges as $(\Delta -1) ^{-1/2}$.
|
Remarks on N_c dependence of decays of exotic baryons | We calculate the N_c dependence of the decay widths of exotic eikosiheptaplet
within the framework of Chral Quark Soliton Model. We also discuss
generalizations of regular baryon representations for arbitrary N_c.
|
Quark matter and the astrophysics of neutron stars | Some of the means through which the possible presence of nearly deconfined
quarks in neutron stars can be detected by astrophysical observations of
neutron stars from their birth to old age are highlighted.
|
A schematic model of scattering in PT-symmetric Quantum Mechanics | One-dimensional scattering problem admitting a complex, PT-symmetric
short-range potential V(x) is considered. Using a Runge-Kutta-discretized
version of Schroedinger equation we derive the formulae for the reflection and
transmission coefficients and emphasize that the only innovation emerges in
fact via a complexification of one of the potential-characterizing parameters.
|
The exact asymptotic of the collision time tail distribution for
independent Brownian particles with different drifts | In this note we consider the time of the collision $\tau$ for $n$ independent
Brownian motions $X^1_t,...,X_t^n$ with drifts $a_1,...,a_n$, each starting
from $x=(x_1,...,x_n)$, where $x_1<...<x_n$. We show the exact asymptotics of
$P_x(\tau>t) = C h(x)t^{-\alpha}e^{-\gamma t}(1 + o(1))$ as $t\to\infty$ and
identify $C,h(x),\alpha,\gamma$ in terms of the drifts.
|
On Almost Periodicity Criteria for Morphic Sequences in Some Particular
Cases | In some particular cases we give criteria for morphic sequences to be almost
periodic (=uniformly recurrent). Namely, we deal with fixed points of
non-erasing morphisms and with automatic sequences. In both cases a
polynomial-time algorithm solving the problem is found. A result more or less
supporting the conjecture of decidability of the general problem is given.
|
Interpolating and sampling sequences in finite Riemann surfaces | We provide a description of the interpolating and sampling sequences on a
space of holomorphic functions with a uniform growth restriction defined on
finite Riemann surfaces.
|
Comments on ``Are Swift Gamma-Ray Bursts consistent with the Ghirlanda
relation?", by Campana et al.(astro--ph/0703676) | In their recent paper, Campana et al. (2007) found that 5 bursts, among those
detected by Swift, are outliers with respect to the E_peak-E_gamma
("Ghirlanda") correlation. We instead argue that they are not.
|
Curvature flows in semi-Riemannian manifolds | We prove that the limit hypersurfaces of converging curvature flows are
stable, if the initial velocity has a weak sign, and give a survey of the
existence and regularity results.
|
Masers and star formation | Recent observational and theoretical advances concerning astronomical masers
in star forming regions are reviewed. Major masing species are considered
individually and in combination. Key results are summarized with emphasis on
present science and future prospects.
|
On Existence of Boundary Values of Polyharmonic Functions | In trigonometric series terms all polyharmonic functions inside the unit disk
are described. For such functions it is proved the existence of their boundary
values on the unit circle in the space of hyperfunctions. The necessary and
sufficient conditions are presented for the boundary value to belong to certain
subspaces of the space of hyperfunctions.
|
Turbulent Diffusion of Lines and Circulations | We study material lines and passive vectors in a model of turbulent flow at
infinite-Reynolds number, the Kraichnan-Kazantsev ensemble of velocities that
are white-noise in time and rough (Hoelder continuous) in space. It is argued
that the phenomenon of ``spontaneous stochasticity'' generalizes to material
lines and that conservation of circulations generalizes to a ``martingale
property'' of the stochastic process of lines.
|
Gluon Radiation of an Expanding Color Skyrmion in the Quark-Gluon Plasma | The density of states and energy spectrum of the gluon radiation are
calculated for the color current of an expanding hydrodynamic skyrmion in the
quark gluon plasma with a semiclassical method. Results are compared with those
in literatures.
|
The Source of Turbulence in Astrophysical Disks: An Ill-posed Problem. | An critical overview of the current state of research in turbulence in
astrophysical disks.
|
On Punctured Pragmatic Space-Time Codes in Block Fading Channel | This paper considers the use of punctured convolutional codes to obtain
pragmatic space-time trellis codes over block-fading channel. We show that good
performance can be achieved even when puncturation is adopted and that we can
still employ the same Viterbi decoder of the convolutional mother code by using
approximated metrics without increasing the complexity of the decoding
operations.
|
On the Markov trace for Temperley--Lieb algebras of type $E_n$ | We show that there is a unique Markov trace on the tower of Temperley--Lieb
type quotients of Hecke algebras of Coxeter type $E_n$ (for all $n \geq 6$). We
explain in detail how this trace may be computed easily using tom Dieck's
calculus of diagrams. As applications, we show how to use the trace to show
that the diagram representation is faithful, and to compute leading
coefficients of certain Kazhdan--Lusztig polynomials.
|
Second Order Perturbative Calculation of Quasinormal Modes of
Schwarzschild Black Holes | We analytically calculate to second order the correction to the asymptotic
form of quasinormal frequencies of four dimensional Schwarzschild black holes
based on the monodromy analysis proposed by Motl and Neitzke. Our results are
in good agreement with those obtained from numerical calculation.
|
Mathematics of thermoacoustic tomography | The paper presents a survey of mathematical problems, techniques, and
challenges arising in the Thermoacoustic and Photoacoustic Tomography.
|
QED x QCD Resummation and Shower/ME Matching for LHC Physics | We present the theory of QED x QCD resummation and its interplay with
shower/matrix element matching in precision LHC physics scenarios. We
illustrate the theory using single heavy gauge boson production at hadron
colliders.
|
The small deviations of many-dimensional diffusion processes and
rarefaction by boundaries | We lead the algorithm of expansion of sojourn probability of many-dimensional
diffusion processes in small domain. The principal member of this expansion
defines normalizing coefficient for special limit theorems.
|
General sequential quantum cloning | Some multipartite quantum states can be generated in a sequential manner
which may be implemented by various physical setups like microwave and optical
cavity QED, trapped ions, and quantum dots etc. We analyze the general N to M
qubits Universal Quantum Cloning Machine (UQCM) within a sequential generation
scheme. We show that the N to M sequential UQCM is available. The case of
d-level quantum states sequential cloning is also presented.
|
Symmetries by base substitutions in the genetic code predict 2' or 3'
aminoacylation of tRNAs | This letter reports complete sets of two-fold symmetries between partitions
of the universal genetic code. By substituting bases at each position of the
codons according to a fixed rule, it happens that properties of the degeneracy
pattern or of tRNA aminoacylation specificity are exchanged.
|
Optical properties of the Holstein-t-J model from dynamical mean-field
theory | We employ dynamical mean-field theory to study the optical conductivity
$\sigma(\omega)$ of one hole in the Holstein-t-J model. We provide an exact
solution for $\sigma(\omega)$ in the limit of infinite connectivity. We apply
our analysis to Nd$_{2-x}$Ce$_x$CuO$_4$. We show that our model can explain
many features of the optical conductivity in this compounds in terms of
magnetic/lattice polaron formation.
|
Infrared Evolution Equations: Method and Applications | It is a brief review on composing and solving Infrared Evolution Equations.
They can be used in order to calculate amplitudes of high-energy reactions in
different kinematic regions in the double-logarithmic approximation.
|
The Blazar Spectral Sequence and GLAST | The present status and understanding of the "spectral sequence" of blazars is
discussed in the perspective of the upcoming GLAST launch. The vast improvement
in sensitivity will allow to i) determine more objectively the "average"
gamma-ray properties of classes objects ii) probe more deeply the ratio between
accretion power and jet power in different systems.
|
Resolvent estimates related with a class of dispersive equations | We present a simple proof of the resolvent estimates of elliptic Fourier
multipliers on the Euclidean space, and apply them to the analysis of
time-global and spatially-local smoothing estimates of a class of dispersive
equations. For this purpose we study in detail the properties of the
restriction of Fourier transform on the unit cotangent sphere associated with
the symbols of multipliers.
|
What can emission lines tell us? | 1 Generalities
2 Empirical diagnostics based on emission lines
3 Photoionization modelling
4 Pending questions
5 Appendix: Lists of useful lines and how to deal with them
|
Flavor Physics in SUSY at large tan(beta) | We discuss the phenomenological impact of a particularly interesting corner
of the MSSM: the large tan(beta) regime. The capabilities of leptonic and
hadronic Flavor Violating processes in shedding light on physics beyond the
Standard Model are reviewed. Moreover, we show that tests of Lepton
Universality in charged current processes can represent an interesting handle
to obtain relevant information on New Physics scenarios.
|
Some properties of the complex Monge-Ampere operator in Cegrell's
classes and applications | In this article we will first prove a result about convergence in capacity.
Using the achieved result we will obtain a general decompositon theorem for
complex Monge-Ampere measues which will be used to prove a comparison principle
for the complex Monge-Ampere operator.
|
B --> rho K* decays and other rare vector-vector modes | The recent analyses of the following rare vector-vector decays of the B meson
are presented: rho K*, omega K*, omega rho, omega omega, and omega phi
charmless final states. The latest results indicate that the fraction of
longitudinal polarization is about 0.5 in penguin-dominated modes and close to
1 for tree-dominated modes.
|
Gravity-induced electric polarization of matter and planetary magnetic
fields | This paper has been withdrawn due to copyright reasons.
|
Capturing knots in polymers | This paper visualizes a knot reduction algorithm
|
Dual billiards, Fagnano orbits and regular polygons | We study the notion of Fagnano orbits for dual polygonal billiards. We used
them to characterize regular polygons and we study the iteration of the
developing map.
|
Average optimality for risk-sensitive control with general state space | This paper deals with discrete-time Markov control processes on a general
state space. A long-run risk-sensitive average cost criterion is used as a
performance measure. The one-step cost function is nonnegative and possibly
unbounded. Using the vanishing discount factor approach, the optimality
inequality and an optimal stationary strategy for the decision maker are
established.
|
The S-Matrix of AdS/CFT and Yangian Symmetry | We review the algebraic construction of the S-matrix of AdS/CFT. We also
present its symmetry algebra which turns out to be a Yangian of the centrally
extended su(2|2) superalgebra.
|
To the origin of the difference of FSI phases in $B\to\pi\pi$ and
$B\to\rho\rho$ decays | The final state interactions (FSI) model in which soft rescattering of low
mass intermediate states dominates is suggested. It explains why the strong
interaction phases are large in the $B_d\to\pi\pi$ channel and are considerably
smaller in the $B_d\to\rho\rho$ one. Direct CP asymmetries of $B_d\to\pi\pi$
decays which are determined by FSI phases are considered as well.
|
On the over-barrier reflection in quantum mechanics with multiple
degrees of freedom | We present an analytic example of two dimensional quantum mechanical system,
where the exponential suppression of the probability of over-barrier reflection
changes non-monotonically with energy. The suppression is minimal at certain
"optimal" energies where reflection occurs with exponentially larger
probability than at other energies.
|
Unit groups of integral finite group rings with no noncyclic abelian
finite subgroups | It is shown that in the units of augmentation one of an integral group ring
$\mathbb{Z} G$ of a finite group $G$, a noncyclic subgroup of order $p^{2}$,
for some odd prime $p$, exists only if such a subgroup exists in $G$. The
corresponding statement for $p=2$ holds by the Brauer--Suzuki theorem, as
recently observed by W. Kimmerle.
|
Thermodynamic Stability - A note on a footnote in Ruelle's book | Thermodynamic stable interaction pair potentials which are not of the form
``positive function + real continuous function of positive type'' are presented
in dimension one. Construction of such a potential in dimension two is
sketched. These constructions use only elementary calculations. The
mathematical background is discussed separately.
|
The Hourglass - Consequences of Pure Hamiltonian Evolution of a
Radiating System | Hourglass is the name given here to a formal isolated quantum system that can
radiate. Starting from a time when it defines the system it represents clearly
and no radiation is present, it is given straightforward Hamiltonian evolution.
The question of what significance hourglasses have is raised, and this question
is proposed to be more consequential than the measurement problem.
|
Polarization conversion in a silica microsphere | We experimentally demonstrate controlled polarization-selective phenomena in
a whispering gallery mode resonator. We observed efficient ($\approx 75 %$)
polarization conversion of light in a silica microsphere coupled to a tapered
optical fiber with proper optimization of the polarization of the propagating
light. A simple model treating the microsphere as a ring resonator provides a
good fit to the observed behavior.
|
Protein and ionic surfactants - promoters and inhibitors of contact line
pinning | We report a new effect of surfactants in pinning a drop contact line,
specifically that lysozyme promotes while lauryl sulfate inhibits pinning. We
explain the pinning disparity assuming difference in wetting: the protein-laden
drop wets a "clean" surface and the surfactant-laden drop wets an
auto-precursored surface.
|
Dynamics of a quantum phase transition in a ferromagnetic Bose-Einstein
condensate | We discuss dynamics of a slow quantum phase transition in a spin-1
Bose-Einstein condensate. We determine analytically the scaling properties of
the system magnetization and verify them with numerical simulations in a one
dimensional model.
|
Neutron-neutron scattering length from the reaction gamma d --> pi^+ nn
employing chiral perturbation theory | We discuss the possibility to extract the neutron-neutron scattering length
a_{nn} from experimental spectra on the reaction gamma d --> pi^+ nn. The
transition operator is calculated to high accuracy from chiral perturbation
theory. We argue that for properly chosen kinematics, the theoretical
uncertainty of the method can be as low as 0.1 fm.
|
The classification of surfaces with p_g=q=1 isogenous to a product of
curves | A projective surface S is said to be isogenous to a product if there exist
two smooth curves C, F and a finite group G acting freely on C \times F so that
S=(C \times F)/G. In this paper we classify all surfaces with p_g=q=1 which are
isogenous to a product.
|
Manipulating the rotational properties of a two-component Bose gas | A rotating, two-component Bose-Einstein condensate is shown to exhibit
vortices of multiple quantization, which are possible due to the interatomic
interactions between the two species. Also, persistent currents are absent in
this system. Finally, the order parameter has a very simple structure for a
range of angular momenta.
|
Contrasting Two Transformation-Based Methods for Obtaining Absolute
Extrema | In this note we contrast two transformation-based methods to deduce absolute
extrema and the corresponding extremizers. Unlike variation-based methods, the
transformation-based ones of Carlson and Leitmann and the recent one of Silva
and Torres are direct in that they permit obtaining solutions by inspection.
|
The affine part of the Picard scheme | We describe the maximal torus and maximal unipotent subgroup of the Picard
variety of a proper scheme over a perfect field.
|
Enhanced quantum Zeno effect and bunching in the decay of interacting
bosons from an unstable state | paper withdrawn due to the possible error in numerical eigenfunction
calculation
|
Long Distance Signaling Using Axion-like Particles | The possible existence of axion-like particles could lead to a new type of
long distance communication. In this work, basic antenna concepts are defined
and a Friis-like equation is derived to facilitate long-distance link
calculations. An example calculation is presented showing that communication
over distances of 1000 km or more may be possible for $m_{a}< 3.5$ meV and
$g_{a\gamma \gamma} > 5 \times 10^{- 8} {\text{GeV}}^{- 1}$.
|
Penalization approach for mixed hyperbolic systems with constant
coefficients satisfying a Uniform Lopatinski Condition | In this paper, we describe a new, systematic and explicit way of
approximating solutions of mixed hyperbolic systems with constant coefficients
satisfying a Uniform Lopatinski Condition via different Penalization
approaches.
|
On the polynomial automorphisms of a group | We prove that if a group is nilpotent (resp. metabelian), then so is the
subgroup of its automorphism group generated by all polynomial automorphisms.
|
Manifolds admitting a $\tilde G_2$-structure | We find a necessary and sufficient condition for a compact 7-manifold to
admit a $\tilde G_2$-structure. As a result we find a sufficient condition for
an open 7-manifold to admit a closed 3-form of $\tilde G_2$-type.
|
Compatibility of Exotic States with Neutron Star Observation | We consider the effect of hard core repulsion in the baryon-baryon
interaction at short distance to the properties of a neutron star. We obtain
that, even with hyperons in the interior of a neutron star, the neutron star
mass can be as large as $\sim 2 M_\odot$.
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Axino warm dark matter and $\Omega_b - \Omega_{DM}$ coincidence | We show that axinos, which are dominantly generated by the decay of the
next-to-lightest supersymmetric particles produced from the leptonic $Q$-ball
($L$-ball), become warm dark matter suitable for the solution of the missing
satellite problem and the cusp problem. In addition, $\Omega_b - \Omega_{DM}$
coincidence is naturally explained in this scenario.
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A unified approach to SIC-POVMs and MUBs | A unified approach to (symmetric informationally complete) positive operator
valued measures and mutually unbiased bases is developed in this article. The
approach is based on the use of operator equivalents expanded in the enveloping
algebra of SU(2). Emphasis is put on similarities and differences between
SIC-POVMs and MUBs.
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Hamilton-Jacobi Fractional Sequential Mechanics | As a continuation of Rabei et al. work [11], the Hamilton- Jacobi partial
differential equation is generalized to be applicable for systems containing
fractional derivatives. The Hamilton- Jacobi function in configuration space is
obtained in a similar manner to the usual mechanics. Two problems are
considered to demonstrate the application of the formalism. The result found to
be in exact agreement with Agrawal's formalism.
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On the Energy-Momentum Problem in Static Einstein Universe | This paper has been removed by arXiv administrators because it plagiarizes
gr-qc/0410004, gr-qc/0603075, and others.
This paper also has excessive overlap with the following papers also written
by the authors or their collaborators: gr-qc/0608111, and others.
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Fractional WKB Approximation | Wentzel, Kramers, Brillouin (WKB) approximation for fractional systems is
investigated in this paper using the fractional calculus. In the fractional
case the wave function is constructed such that the phase factor is the same as
the Hamilton's principle function "S". To demonstrate our proposed approach two
examples are investigated in details.
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