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Diffraction : Recent Results and Implications for LHC | With the knowledge of diffractive parton densities extracted from HERA data,
we discuss the observation of exclusive events using the dijet mass fraction as
measured by the CDF collaboration at the Tevatron. In particular the impact of
the gluon density uncertainty is analysed. Some prospects are given for
diffractive physics at the LHC.
|
Every compact group arises as the outer automorphism group of a II_1
factor | We show that any compact group can be realized as the outer automorphism
group of a factor of type II_1. This has been proved in the abelian case by
Ioana, Peterson and Popa applying Popa's deformation/rigidity techniques to
amalgamated free product von Neumann algebras. Our methods are a generalization
of theirs.
|
Comment on ''Measurement of Effective Temperatures in an Aging Colloidal
Glass'' | We measure the fluctuations of the position of a silica bead trapped by an
optical tweezers during the aging of a Laponite suspension. We find that the
effective temperature is equal to the bath temperature.
|
Adding Charges to N=4 Dyons | The spectrum of dyons in a class of N=4 supersymmetric string theories has
been found for a specific set of electric and magnetic charge vectors. We
extend the analysis to more general charge vectors by considering various
charge carrying collective excitations of the original system.
|
On b-function, spectrum and multiplier ideals | We give a survey on b-function, spectrum, and multiplier ideals together with
certain interesting relations among them including the case of arbitrary
subvarieties.
|
Asymptotic velocity of one dimensional diffusions with periodic drift | We consider the asymptotic behaviour of the solution of one dimensional
stochastic differential equations and Langevin equations in periodic
backgrounds with zero average. We prove that in several such models, there is
generically a non vanishing asymptotic velocity, despite of the fact that the
average of the background is zero.
|
Holomorphic quadratic differentials and the Bernstein problem in
Heisenberg space | We classify the entire minimal vertical graphs in the 3 dimensional
Heisenberg group Nil endowed with a Riemannian left-invariant metric. This
classification, which provides a solution to the Bernstein problem in Nil, is
given in terms of the Abresch-Rosenberg holomorphic differential for minimal
surfaces in Nil.
|
Does P=NP? | This paper has been withdrawn Abstract: This paper has been withdrawn by the
author due to the publication.
|
Embedding Degree of Hyperelliptic Curves with Complex Multiplication | Consider the Jacobian of a genus two curve defined over a finite field and
with complex multiplication. In this paper we show that if the l-Sylow subgroup
of the Jacobian is not cyclic, then the embedding degree of the Jacobian with
respect to l is one.
|
Wakes in a Collisional Quark-Gluon Plasma | Wakes created by a parton moving through a static and infinitely extended
quark-gluon plasma are considered. In contrast to former investigations
collisions within the quark-gluon plasma are taken into account using a
transport theoretical approach (Boltzmann equation) with a
Bhatnagar-Gross-Krook collision term. Within this model it is shown that the
wake structure changes significantly compared to the collisionless case.
|
Homotopy Lie algebra of the complements of subspace arrangements with
geometric lattices | Let A be a geometric arrangement such that codim(x) > 1 for every x in A. We
prove that, if the complement space M(A) is rationally hyperbolic, then there
exists an injective from a free Lie algebra L(u,v) to the homotopy Lie algebra
of M(A).
|
A simple uniform approach to complexes arising from forests | In this paper we present a unifying approach to study the homotopy type of
several complexes arising from forests. We show that this method applies
uniformly to many complexes that have been extensively studied.
|
Entanglement Assisted Classical Capacity of a Class of Quantum Channels
with Long-Term Memory | In this paper we evaluate the entanglement assisted classical capacity of a
class of quantum channels with long-term memory, which are convex combinations
of memoryless channels. The memory of such channels can be considered to be
given by a Markov chain which is aperiodic but not irreducible.
|
Many-spinon states and the secret significance of Young tableaux | We establish a one-to-one correspondence between the Young tableaux
classifying the total spin representations of N spins and the exact eigenstates
of the the Haldane-Shastry model for a chain with N sites classified by the
total spins and the fractionally spaced single-particle momenta of the spinons.
|
Nonorientable 3-manifolds admitting coloured triangulations with at most
30 tetrahedra | We present the census of all non-orientable, closed, connected 3-manifolds
admitting a rigid crystallization with at most 30 vertices. In order to obtain
the above result, we generate, manipulate and compare, by suitable computer
procedures, all rigid non-bipartite crystallizations up to 30 vertices.
|
Multiple Solutions for a Henon-Like Equation on the Annulus | For the equation (-\Delta u = | |x|-2 |^\alpha u^{p-1}), (1 < |x| < 3), we
prove the existence of two solutions for (\alpha) large, and of two additional
solutions when (p) is close to the critical Sobolev exponent (2^*=2N/(N-2)). A
symmetry--breaking phenomenon appears, showing that the least--energy solutions
cannot be radial functions.
|
Trivialization of C(X)-algebras with strongly self-absorbing fibres | Suppose $A$ is a separable unital $C(X)$-algebra each fibre of which is
isomorphic to the same strongly self-absorbing and $K_{1}$-injective
$C^{*}$-algebra $D$. We show that $A$ and $C(X) \otimes D$ are isomorphic as
$C(X)$-algebras provided the compact Hausdorff space $X$ is finite-dimensional.
This statement is known not to extend to the infinite-dimensional case.
|
Model independent Breit-Wigner parameters of nucleon resonances
S11(1535), S11(1650) and P11(1710) | Estimates of Breit-Wigner parameters of nucleon resonances were obtained by
phenomenological analysis of eta meson photoproduction on protons performed
completely by statistical procedures without appealing to theoretical models
|
Theta+ width estimation with nonzero momentum transfer | We have used the light-cone formulation of Chiral-Quark Soliton Model to
estimate the width of the lightest pentaquark Theta+. We have found that the
effect of nonzero momentum transfer is important and reduces drastically the
width to about 0.43 MeV. This means that this effect is a piece of the small
width puzzle of exotic baryons.
|
Comment on "note on the derivative of the hyperbolic cotangent" | In a couple of articles (Ford G W and O'Connell R F 1996 Nature 380 113 and
2002 J. Phys. A: Math. Gen. 35 4183) it was argued that the standard result for
the derivative of the hyperbolic cotangent in the literature, d \coth y/dy =
-{csch}^2 y is incomplete and the correct expression should have an additional
term proportional to the Dirac delta function. The purpose of this paper is to
demonstrate that this claim is incorrect.
|
Effect of inelastic collisions on multiphonon Raman scattering in
graphene | We calculate the probabilities of two- and four-phonon Raman scattering in
graphene and show how the relative intensities of the overtone peaks encode
information about relative rates of different inelastic processes electrons are
subject to. If the most important processes are electron-phonon and
electron-electron scattering, the rate of the latter can be deduced from the
Raman spectra.
|
Unfolding Manhattan Towers | We provide an algorithm for unfolding the surface of any orthogonal
polyhedron that falls into a particular shape class we call Manhattan Towers,
to a nonoverlapping planar orthogonal polygon. The algorithm cuts along edges
of a 4x5x1 refinement of the vertex grid.
|
Cluster-type entangled coherent states | We present the cluster-type entangled coherent states (CTECS) and discuss
their properties. A cavity QED generation scheme using suitable choices of
atom-cavity interactions, obtained via detunings adjustments and the
application of classical external fields, is also presented. After the
realization of simple atomic measurements, CTECS representing nonlocal
electromagnetic fields in separate cavities can be generated.
|
Simulating Cosmological Evolution with Enzo | In this paper we describe our massively parallel version of Enzo, a
multiphysics, parallel, AMR application for simulating cosmological structure
formation developed at UCSD and Columbia. We describe its physics, numerical
algorithms, implementation, and performance on current terascale platforms. We
also discuss our future plans and some of the challenges we face as we move to
the petascale.
|
Interior of Distorted Black Holes | We study the interior of distorted static axisymmetric black holes. We obtain
a general interior solution and study its asymptotics both near the horizon and
singularity. As a special example, we apply the obtained results to the case of
the so-called `caged' black holes.
|
Searching for Gravitational Waves from Binary Inspirals with LIGO | We describe the current status of the search for gravitational waves from
inspiralling compact binary systems in LIGO data. We review the result from the
first scientific run of LIGO (S1). We present the goals of the search of data
taken in the second scientific run (S2) and describe the differences between
the methods used in S1 and S2.
|
Axiomatic theory of divergent series and cohomological equations | A general theory of summation of divergent series based on the
Hardy-Kolmogorov axioms is developed. A class of functional series is
investigated by means of ergodic theory. The results are formulated in terms of
solvability of some cohomological equations, all solutions to which are
nonmeasurable. In particular, this realizes a construction of a nonmeasurable
function as first conjectured by Kolmogorov.
|
Mean Field Spin Glass in the Observable Representation | The state space for the $N$-spin mean field (SK) spin glass--nominally an
$N$-cube--is embedded in a low dimensional continuous space in such a way that
metastable and stable phases can easily be discerned, a concept of nearness of
configurations defined, and peaks in the Parisi $q$-parameter overlap
distribution identified. The dynamical and partly hierarchical interrelation of
these phases can be directly imaged.
|
Flavoured Leptogenesis | Thermal leptogenesis, in the seesaw model, is a popular mechanism for
generating the Baryon Asymmetry of the Universe. It was noticed recently, that
including lepton flavour can modify significantly the results. These
proceedings aim to discuss why and when flavour matters, in the thermal
leptogenesis scenario for hierarchical right-handed neutrinos. No Boltzmann
Equations are introduced.
|
Bauer-Furuta invariants under Z_2-actions | S.Bauer and M.Furuta defined a stable cohomotopy refinement of the
Seiberg-Witten invariants. In this paper, we prove a vanishing theorem of
Bauer-Furuta invariants for 4-manifolds with smooth Z/2-actions. As an
application, we give a constraint on smooth Z/2-actions on homotopy K3#K3, and
construct a nonsmoothable locally linear Z/2-action on K3#K3. We also construct
a nonsmoothable locally linear Z/2-action on $K3$.
|
Weight 2 blocks of general linear groups and modular Alvis-Curtis
duality | We obtain the structure of weight 2 blocks and [2:1]-pairs of q-Schur
algebras, and compute explicitly the modular Alvis-Curtis duality for weight 2
blocks of finite general linear groups in non-defining characteristic.
|
Proof of the Double Bubble Conjecture in R^n | The least-area hypersurface enclosing and separating two given volumes in R^n
is the standard double bubble.
|
Finite Just Non-Dedekind Groups | A group is just non-Dedekind (JND) if it is not a Dedekind group but all of
whose proper homomorphic images are Dedekind groups. The aim of the paper is to
classify finite JND-groups.
|
Comment on "Structure factors of harmonic and anharmonic Fibonacci
chains by molecular dynamics simulations" | Recently, Engel et al. discussed phonon broadening as observed in 3D
quasicrystals on the basis of calculations on the Fibonacci chain. We show that
the paper contains several statements and assumptions that are contradicted by
factual truth.
|
Circularly polarized waves in a plasma with vacuum polarization effects | The theory for large amplitude circularly polarized waves propagating along
an external magnetic field is extended in order to include also vacuum
polarization effects. A general dispersion relation, which unites previous
results, is derived.
|
Unitary spaces on Clifford algebras | For the complex Clifford algebra Cl(p,q) of dimension n=p+q we define a
Hermitian scalar product. This scalar product depends on the signature (p,q) of
Clifford algebra. So, we arrive at unitary spaces on Clifford algebras. With
the aid of Hermitian idempotents we suggest a new construction of, so called,
normal matrix representations of Clifford algebra elements. These
representations take into account the structure of unitary space on Clifford
algebra.
|
Deligne-Lusztig varieties and period domains over finite fields | We prove that the Drinfeld halfspace is essentially the only Deligne-Lusztig
variety which is at the same time a period domain over a finite field. This is
done by comparing a cohomology vanishing theorem for DL-varieties, due to
Digne, Michel, and Rouquier, with a non-vanishing theorem for PD, due to the
first author. We also discuss an affineness criterion for DL-varieties.
|
Chen's double sieve, Goldbach's conjecture and the twin prime problem | We give a more comrehensive treatment of Chen's double sieve and improve
related constants in Goldbach's conjecture and the twin prime problem.
|
The analyticity region of the hard sphere gas. Improved bounds | We find an improved estimate of the radius of analyticity of the pressure of
the hard-sphere gas in $d$ dimensions. The estimates are determined by the
volume of multidimensional regions that can be numerically computed. For $d=2$,
for instance, our estimate is about 40% larger than the classical one.
|
13 New Eclipsing Binaries with Additional Variability in the ASAS
Catalogue | We present 13 new ASAS eclipsing binaries that exhibit additional periodic
variability due to pulsations, eclipses with another period or spots. All
contact and semi-detached binaries from the ASAS Catalogue were investigated.
|
Minimal Walking on the Lattice | We provide the first evidence of a walking dynamics for two color lattice
Yang-Mills theory with two Dirac flavors in the symmetric representation of the
gauge group.
|
q-Deformed Superalgebras | The article deals with q-analogs of the three- and four-dimensional Euclidean
superalgebra and the Poincare superalgebra.
|
Note on Schmidt Decomposition in Infinite Dimensional Hilbert Spaces | This paper has been withdrawn by the author.
|
Observation of higher-order solitons in defocusing waveguide arrays | We observe experimentally higher-order solitons in waveguide arrays with
defocusing saturable nonlinearity. Such solitons can comprise several in-phase
bright spots and are stable above a critical power threshold. We elucidate the
impact of the nonlinearity saturation on the domains of existence and stability
of the observed complex soliton states.
|
Slicing, skinning, and grafting | We prove that a Bers slice is never algebraic, meaning that its Zariski
closure in the character variety has strictly larger dimension. A corollary is
that skinning maps are never constant.
The proof uses grafting and the theory of complex projective structures.
|
A homotopy method for finding eigenvalues and eigenvectors | Suppose we want to find the eigenvalues and eigenvectors for the linear
operator L, and suppose that we have solved this problem for some other
"nearby" operator K. In this paper we show how to represent the eigenvalues and
eigenvectors of L in terms of the corresponding properties of K.
|
Measurement of electro-magnetic radiation at PHENIX | Recent results on direct photons and dileptons from the PHENIX xperiment
opened up a possibility of landscaping electro-magnetic radiation over various
kinetic energies in heavy ion collisions. A detail discussion is given based on
a review of the results.
|
Selfsimilar Equivalence of Porous Medium and p-Laplacian Flows | We demonstrate the equivalence between the two popular models of nonlinear
diffusion, the porous medium equation and the p-Laplacian equation. The
equivalence is shown at the level of selfsimilar solutions.
|
Holomorphic fiber bundle with Stein base and Stein fibers | In this article, we prove that if $\Pi: X\to \Omega$ is a surjective
holomorphic map, with $\Omega$ a Stein space and $X$ a complex manifold of
dimension $n\geq 3,$ and if, for every $x\in \Omega$ there exists an open
neighborhood $U$ such that $\Pi^{-1}(U)$ is Stein, then $X$ is Stein
|
On Vojta's $1+\epsilon$ Conjecture | I gave a geometric proof of Vojta's 1 + epsilon conjecture.
Some gaps in the published paper were spotted and kindly pointed out to me by
Paul Vojta. These were addressed in "Erratum".
|
Astrophysics in 2006 | The fastest pulsar and the slowest nova; the oldest galaxies and the youngest
stars; the weirdest life forms and the commonest dwarfs; the highest energy
particles and the lowest energy photons. These were some of the extremes of
Astrophysics 2006. We attempt also to bring you updates on things of which
there is currently only one (habitable planets, the Sun, and the universe) and
others of which there are always many, like meteors and molecules, black holes
and binaries.
|
Fibers of tropicalization | We use functoriality of tropicalization and the geometry of projections of
subvarieties of tori to show that the fibers of the tropicalization map are
dense in the Zariski topology. For subvarieties of tori over fields of
generalized power series, points in each tropical fiber are obtained
"constructively" using Kedlaya's transfinite version of Newton's method.
|
The Large Sieve Inequality for Quadratic Polynomial Amplitudes | We provide here a modest improvement upon a large sieve inequality for
quadratic polynomial amplitudes orginally due to Liangyi Zhao.
|
Nonlocal Double-Slit Interference with Pseudothermal Light | We perform a nonlocal double-slit interference experiment with pseudothermal
light. The experimental result exhibits a typical double-slit interference
fringe in the intensity correlation measurement, in agreement with the
theoretical analysis by means of the property of the second-order spatial
correlation of field.
|
Nonlinarity of Boolean functions and hyperelliptic curves | We study the nonlinearity of functions defined on a finite field with 2^m
elements which are the trace of a polynomial of degree 7 or more general
polynomials. We show that for m odd such functions have rather good
nonlinearity properties. We use for that recent results of Maisner and Nart
about zeta functions of supersingular curves of genus 2. We give some criterion
for a vectorial function not to be almost perfect nonlinear.
|
Is the Pentaquark the Only Justification for Research on KN Physics ? | The talk is intended to motivate the use of DA$\Phi$NE--2 running at the
$\phi$ peak as an intense, clean source of low--momentum charged and neutral
kaons. It covers a few open problems still unsolved after more than
twenty--five years and the physics (some of it still novel) that could be
learned only in this way. And, of course, the answer to the above question is
{\sl NO}.
|
A New Class of String Cosmological Models in Cylindrically Symmetric
Inhomogeneous Universe | A new class of cylindrically symmetric inhomogeneous string cosmological
models is investigated. To get the deterministic solution, it has been assumed
that the expansion ($\theta$) in the model is proportional to the eigen value
$\sigma^{1}_{1}$ of the shear tensor $\sigma^{i}_{j}$. The physical and
geometric aspects of the model are also discussed.
|
Recursive Parameter Estimation: Convergence | We consider estimation procedures which are recursive in the sense that each
successive estimator is obtained from the previous one by a simple adjustment.
We propose a wide class of recursive estimation procedures for the general
statistical model and study convergence.
|
Rate of Convergence in Recursive Parameter Estimation procedures | We consider estimation procedures which are recursive in the sense that each
successive estimator is obtained from the previous one by a simple adjustment.
We study rate of convergence of recursive estimation procedures for the general
statistical model.
|
Ultraviolet properties of f(R)-Gravity | We discuss the existence and properties of a nontrivial fixed point in
f(R)-gravity, where f is a polynomial of order up to six. Within this
seven-parameter class of theories, the fixed point has three
ultraviolet-attractive and four ultraviolet-repulsive directions; this brings
further support to the hypothesis that gravity is nonperturbatively
renormalizabile.
|
Saltation transport on Mars | We present the first calculation of saltation transport and dune formation on
Mars and compare it to real dunes. We find that the rate at which grains are
entrained into saltation on Mars is one order of magnitude higher than on
Earth. With this fundamental novel ingredient, we reproduce the size and
different shapes of Mars dunes, and give an estimate for the wind velocity on
Mars.
|
Gauge Theory of the Star Product | The choice of a star product realization for noncommutative field theory can
be regarded as a gauge choice in the space of all equivalent star products.
With the goal of having a gauge invariant treatment, we develop tools, such as
integration measures and covariant derivatives on this space. The covariant
derivative can be expressed in terms of connections in the usual way giving
rise to new degrees of freedom for noncommutative theories.
|
Subjective Questions and Answers for a Mathematics Instructor of Higher
Education | This article of mathematical education reflects author's experience with job
applications and teaching methods and procedures to employ in the American
Higher Education. It is organized as a standard questionnaire.
|
Comment on six papers published by M.A. El-Hakiem and his co-workers in
International Communications in Heat and Mass Transfer, Journal of Magnetism
and Magnetic Materials and Heat and Mass Transfer | Comment on six papers published by M.A. El-Hakiem and his co-workers in
International Communications in Heat and Mass Transfer, Journal of Magnetism
and Magnetic Materials and Heat and Mass Transfer
|
Entropy exchange, coherent information and concurrence | For a simple model we derive analytic expressions of entropy exchange and
coherent information, from which relations between them and the concurrence are
drawn. We find that in the quantum evolution the entropy exchange exhibits
behavior \textsl{opposite} to that of the concurrence, whereas the coherent
information shows features very similar to those of the concurrence. The
meaning of this result for general systems is discussed.
|
Unitary transformations can be identified locally | We show that in principle, $N$-partite unitary transformations can be
perfectly discriminated under local measurement and classical communication
(LOCC) despite of their nonlocal properties. Based on this result, some related
topics, including the construction of the appropriate quantum circuit together
with the extension to general completely positive trace preserving operations,
are discussed.
|
Nonlinear optics and light localization in periodic photonic lattices | We review the recent developments in the field of photonic lattices
emphasizing their unique properties for controlling linear and nonlinear
propagation of light. We draw some important links between optical lattices and
photonic crystals pointing towards practical applications in optical
communications and computing, beam shaping, and bio-sensing.
|
Anticipated backward stochastic differential equations | In this paper we discuss new types of differential equations which we call
anticipated backward stochastic differential equations (anticipated BSDEs). In
these equations the generator includes not only the values of solutions of the
present but also the future. We show that these anticipated BSDEs have unique
solutions, a comparison theorem for their solutions, and a duality between them
and stochastic differential delay equations.
|
Bounds to unitary evolution | Upper and lower bounds are established for the survival probability
$|<\psi(0)|\psi(t)>|^{2}$ of a quantum state, in terms of the energy moments
$<\psi(0)|H^{n}|\psi(0)>$. Introducing a cut-off in the energy generally
enables considerable improvement in these bounds and allows the method to be
used where the exact energy moments do not exist.
|
Radon transform on real symmetric varieties: kernel and cokernel | We define and study the (minimal) Radon transform on a real symmetric
variety.
|
Remark on the Garnier system in two variables | We remark on the Garnier system in two variables.
|
Cohen-Macaulay multigraded modules | Let S be a standard N^r-graded algebra over a local ring A, and let M be a
finitely generated Z^r-graded S-module. We characterize the Cohen-Macaulayness
of M in terms of the vanishing of certain sheaf cohomology modules. As a
consequence, we apply our result to study the Cohen-Macaulayness of multi-Rees
modules (also called Rees modification). Our work extends previous studies on
the Cohen-Macaulayness of multi-Rees algebras.
|
Black Saturn with dipole ring | We present a new stationary, asymptotically flat solution of 5D
Einstein-Maxwell gravity describing a Saturn-like black object: a rotating
black hole surrounded by a rotating dipole black ring. The solution is
generated by combining the vacuum black Saturn solution and the vacuum black
ring solution with appropriately chosen parameters. Some basic properties of
the solution are analyzed and the basic quantities are calculated.
|
Design of quasi-symplectic propagators for Langevin dynamics | A vector field splitting approach is discussed for the systematic derivation
of numerical propagators for deterministic dynamics. Based on the formalism, a
class of numerical integrators for Langevin dynamics are presented for single
and multiple timestep algorithms.
|
Revesibility of chordal SLE | We prove that the chordal SLE$_\kappa$ trace is reversible for
$\kappa\in(0,4]$.
|
On the Green's matrices of strongly parabolic systems of second order | We establish existence and various estimates of fundamental matrices and
Green's matrices for divergence form, second order strongly parabolic systems
in arbitrary cylindrical domains under the assumption that solutions of the
systems satisfy an interior H\"{o}lder continuity estimate. We present a
unified approach valid for both the scalar and the vectorial cases.
|
Quantization of Donaldson-Uhlenbeck-Yau theory | A covariant path-integral quantization is proposed for the non-Lagrangian
gauge theory described by the Donaldson-Uhlenbeck-Yau equation. The
corresponding partition function is shown to admit a nice path-integral
representation in terms of the gauged G/G K\"ahler WZW model. A relationship
with the $J$-formulation of the anti-self-dual Yang-Mills theory is explored.
|
On Mordell-Weil groups of elliptic curves induced by Diophantine triples | We study the possible structure of the groups of rational points on elliptic
curves of the form y^2=(ax+1)(bx+1)(cx+1), where a,b,c are non-zero rationals
such that the product of any two of them is one less than a square.
|
Charged hadron R_AA as a function of p_T at the LHC | We compute the nuclear suppression factor R_AA for charged hadrons within a
radiative energy loss picture using a hydrodynamical evolution to describe the
soft medium inducing energy loss. A minijet + saturation picture provides
initial conditions for LHC energies and leading order perturbative QCD (LO
pQCD) is used to compute the parton spectrum before distortion by energy loss.
|
Weyl Projective Curvature Symmetry in FRW k=0 Model | A study of proper Weyl projective curvature collineations in FRW k=0
space-time is given using the rank of Weyl projective curvature matrix and
direct integration techniques. It is shown that a very special class of the
above space-time admits proper Weyl projective curvature collineation.
|
Asymptotic freedom in massive Yang-Mills theory | An effective field theory model of the massive Yang-Mills theory is
considered. Assuming that the renormalized coupling constants of
'non-renormalizable' interactions are suppressed by a large scale parameter it
is shown that in analogy to the non-abelian gauge invariant theory the
dimensionless coupling constant vanishes logarithmically for large values of
the renormalization scale parameter.
|
The dipole form of the gluon part of the BFKL kernel | The dipole form of the gluon part of the colour singlet BFKL kernel in the
next-to-leading order (NLO) is obtained in the coordinate representation by
direct transfer from the momentum representation, where the kernel was
calculated before. With this paper the transformation of the NLO BFKL kernel to
the dipole form, started a few months ago with the quark part of the kernel, is
completed.
|
On Possibilities of Studying of Supernova Neutrinos at BAKSAN | We consider the possibilities of studying a supernova collapse neutrino burst
at Baksan Neutrino Observatory (Institute for Nuclear Research, Russian Academy
of Sciences) using the prposed 5-kt target-mass liquid scintillation
spectrometer. Attention is given to the influence of mixing angle
${\theta}_{13}$ on the expected rates and spectra of neutrino events.
|
Self-duality of Selmer groups | The first part of the paper gives a new proof of self-duality for Selmer
groups: if A is an abelian variety over a number field K, and F/K is a Galois
extension with Galois group G, then the Q_pG-representation naturally
associated to the p-infinity Selmer group of A/F is self-dual. The second part
describes a method for obtaining information about parities of Selmer ranks
from the local Tamagawa numbers of A in intermediate extensions of F/K.
|
Necessary Conditions for Geometric Realizability of Simplicial Complexes | We associate with any simplicial complex $\K$ and any integer $m$ a system of
linear equations and inequalities. If $\K$ has a simplicial embedding in $\R^m$
then the system has an integer solution. This result extends the work of I.
Novik (2000).
|
Phases of QCD: Summary of the Rutgers Long Range Plan Town Meeting | This White Paper summarizes the outcome of the Town Meeting on Phases of QCD
that took place January 12-14, 2007 at Rutgers University, as part of the NSAC
2007 Long Range Planning process.
|
Accurate predictions for heavy quark jets | Heavy-flavour jets enter many of today's collider studies, yet NLO
predictions for these quantities are subject to large uncertainties, larger
than the corresponding experimental errors. We propose a new, infrared safe
definition of heavy-quark jets which allows one to reduce theoretical
uncertainties by a factor of three.
|
Ideals of varieties parameterized by certain symmetric tensors | The ideal of a Segre variety is generated by the 2-minors of a generic
hypermatrix of indeterminates. We extend this result to the case of
Segre-Veronese varieties. The main tool is the concept of weak generic
hypermatrix which allows us to treat also the case of projection of Veronese
surfaces from a set of generic points and of Veronese varieties from a
Cohen-Macaulay subvariety of codimension 2.
|
The non-equilibrium work relation. Thermodynamic analysis and
microscopic foundations | We discuss the conditions for which the non-equilibrium work relation is
valid by means of thermodynamic and microscopic arguments.
|
Riesz and Szeg\"o type factorizations for noncommutative Hardy spaces | Let $\A$ be a finite subdiagonal algebra in Arveson's sense. Let $H^p(\A)$ be
the associated noncommutative Hardy spaces, $0<p\le\8$. We extend to the case
of all positive indices most recent results about these spaces, which include
notably the Riesz, Szeg\"o and inner-outer type factorizations. One new tool of
the paper is the contractivity of the underlying conditional expectation on
$H^p(\A)$ for $p<1$.
|
Correlated multi-asset portfolio optimisation with transaction cost | We employ perturbation analysis technique to study multi-asset portfolio
optimisation with transaction cost. We allow for correlations in risky assets
and obtain optimal trading methods for general utility functions. Our
analytical results are supported by numerical simulations in the context of the
Long Term Growth Model.
|
Sums of lens spaces bounding rational balls | We classify connected sums of three-dimensional lens spaces which smoothly
bound rational homology balls. We use this result to determine the order of
each lens space in the group of rational homology 3-spheres up to rational
homology cobordisms, and to determine the concordance order of each 2-bridge
knot.
|
Z boson decay to photon plus Kaluza-Klein graviton in large extra
dimensions | In the large extra dimensional ADD scenario, Z bosons undergo a one-loop
decay into a photon and Kaluza-Klein towers of gravitons/gravi-scalars. We
calculate such a decay width, extending previous arguments about the general
form of the four-dimensional on-shell amplitude. The amplitudes calculated are
relevant to processes in other extra dimensional models where the Standard
Model fields are confined to a 4-brane.
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Intersections of polynomial orbits, and a dynamical Mordell-Lang
conjecture | We prove that if nonlinear complex polynomials of the same degree have orbits
with infinite intersection, then the polynomials have a common iterate. We also
prove a special case of a conjectured dynamical analogue of the Mordell-Lang
conjecture.
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R-symmetry breaking, runaway directions and global symmetries in
O'Raifeartaigh models | We discuss O'Raifeartaigh models with general R-charge assignments,
introduced by Shih to break R-symmetry spontaneously. We argue that most of
these models have runaway directions related to the R-symmetry. In addition, we
study the simplest model with a U(N) global symmetry and show that in a range
of parameters R-symmetry is spontaneously broken in a metastable vacuum.
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An Explicit Computation of the Bures Metric Over the Space of
$N$-Dimensional Density Matrices | The aim of this paper is to provide a method for explicit computation of the
Bures metric over the space of $N$-level quantum system, based on the coset
parametrization of density matrices.
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All-order consistency of 5d sugra vacua | We show that the maximally supersymmetric vacua of d=5 N=1 sugra remain
maximally supersymmetric solutions when taking into account higher order
corrections.
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Quantum Correlation Without Classical Correlations | We show that genuine multiparty quantum correlations can exist on its own,
without a supporting background of genuine multiparty classical correlations,
even in macroscopic systems. Such possibilities can have important implications
in the physics of quantum information and phase transitions.
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Correlations with Photons in Heavy-Ion Collisions | We present a study of two-particle correlation functions involving photons
and neutral pions in proton-proton and lead-lead collisions at the LHC energy.
The aim is to use these correlation functions to quantify the effects of the
medium on the jet decay properties.
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Reconstruction from Radon projections and orthogonal expansion on a ball | The relation between Radon transform and orthogonal expansions of a function
on the unit ball in $\RR^d$ is exploited. A compact formula for the partial
sums of the expansion is given in terms of the Radon transform, which leads to
algorithms for image reconstruction from Radon data. The relation between
orthogonal expansion and the singular value decomposition of the Radon
transform is also exploited.
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