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Integral group ring of the Mathieu simple group M24 | We consider the Zassenhaus conjecture for the normalized unit group of the
integral group ring of the Mathieu sporadic group $M_{24}$. As a consequence,
for this group we confirm Kimmerle's conjecture on prime graphs.
|
Minimal Pati-Salam Model from String Theory Unification | We provide what we believe is the minimal three family ${\cal N} = 1$ SUSY
and conformal Pati-Salam Model from type IIB superstring theory. This $Z_3$
orbifolded AdS$\otimes S^5$ model has long lived protons and has potential
phenomenological consequences for LHC.
|
Critique of "Quantum Enigma:Physic encounters Consciousness" | The central claim that understanding quantum mechanics requires a conscious
observer, which is made made by B. Rosenblum and F. Kuttner in their book
"Quantum Enigma: Physics encounters consciousnes", is shown to be based on
various misunderstandings and distortions of the foundations of quantum
mechanics.
|
Energy of zeros of random sections on Riemann Surface | The purpose of this paper is to determine the asymptotic of the average
energy of a configuration of N zeros of system of random polynomials of degree
N as N tends to infinity and more generally the zeros of random holomorphic
sections of a line bundle L over any Riemann surface M. And we compare our
results to the well-known minimum of energies.
|
Search for $t\bar{t}$ resonances with the ATLAS detector | This paper has been withdrawn by the authors due to the violation of ATLAS
experiment publication policy.
|
Dynamics of excitations in a one-dimensional Bose liquid | We show that the dynamic structure factor of a one-dimensional Bose liquid
has a power-law singularity defining the main mode of collective excitations.
Using the Lieb-Liniger model, we evaluate the corresponding exponent as a
function of the wave vector and the interaction strength.
|
Head-On collisions of different initial data | We discuss possible origins for discrepancies observed in the radiated
energies in head-on collisions of non-spinning binaries starting from
Brill-Lindquist and superposed Kerr-Schild data. For this purpose, we discuss
the impact of different choices of gauge parameters and a small initial boost
of the black holes.
|
Controlled vortex core switching in a magnetic nanodisk by a rotating
field | The switching process of the vortex core in a Permalloy nanodisk affected by
a rotating magnetic field is studied theoretically. A detailed description of
magnetization dynamics is obtained by micromagnetic simulations.
|
On Constructing Baby Universes and Black Holes | The creation of spacetimes with horizons is discussed, focussing on baby
universes and black holes as examples. There is a complex interplay of quantum
theory and General Relativity in both cases, leading to consequences for the
future of the universe and the information loss paradox, and to a deeper
understanding of quantum gravity.
|
The Maximal Integral Domain Generated By A Commutative Ring | In this paper, we exhibit the creation of the maximal integral domain mid(R)
generated by a nonzero commutative ring R.
|
Tensor Product of the Fundamental Representations for the Quantum Loop
Algebras of Type A at Roots of Unity | In this paper, we consider the necessary and sufficient conditions for the
tensor product of the fundamental representations for the restricted quantum
loop algebras of type A at roots of unity to be irreducible.
|
Vanishing and injectivity theorems for LMMP | This preprint has been withdrawn. It is because I will never publish this
preprint since everything has been contained in my new preprint:
arXiv:0907.1506. Please refer to arXiv:0907.1506. Please do not cite this
preprint any more.
|
Notes on the log minimal model program | This preprint has been withdrawn. It is because I will never publish this
preprint since everything has been contained in my new preprint:
arXiv:0907.1506. Please refer to arXiv:0907.1506. Please do not cite this
preprint any more.
|
The abelianization of a symmetric mapping class group | We determine the abelianization of the symmetric mapping class group of a
double unbranched cover using the Riemann theta constant, Schottky theta
constant, and the theta multiplier. We also give lower bounds of the
abelianizations of some finite index subgroups of the mapping class group.
|
Solution Of Wheeler-De Witt Equation, Potential Well And Tunnel Effect | This paper uses the relation of the cosmic scale factor and scalar field to
solve Wheeler-DeWitt equation, gives the tunnel effect of the cosmic scale
factor a and quantum potential well of scalar field, and makes it fit with the
physics of cosmic quantum birth. By solving Wheeler-DeWitt equation we achieve
a general probability distribution of the cosmic birth, and give the analysis
of cosmic quantum birth.
|
Mirzakharni's recursion formula is equivalent to the Witten-Kontsevich
theorem | In this paper, we give a proof of Mirzakhani's recursion formula of
Weil-Petersson volumes of moduli spaces of curves using the Witten-Kontsevich
theorem. We also describe properties of intersections numbers involving higher
degree $\kappa$ classes.
|
Another property of minimal surfaces in Euclidean space | The new property of minimal surfaces is obtained in this article.
|
Smooth multiparameter perturbation of polynomials and operators | This paper has been withdrawn by the authors due to a gap in the proof of the
main result (in 5.3).
|
Casimir operators, abelian subspaces and u-cohomology | This survey paper is an exposition of old and recent results of Kostant and
al. on the relationships between the exterior algebra of a simple Lie algebra
and the action of the Casimir operator on it. Our exposition relies on
u-cohomology and it is basically self-contained.
|
The General Definition of the Complex Monge-Amp\`ere Operator on Compact
K\"ahler Manifolds | We introduce a wide subclass ${\cal F}(X,\omega)$ of quasi-plurisubharmonic
functions in a compact K\"ahler manifold, on which the complex Monge-Amp\`ere
operator is well-defined and the convergence theorem is valid. We also prove
that ${\cal F}(X,\omega)$ is a convex cone and includes all
quasi-plurisubharmonic functions which are in the Cegrell class.
|
Method to measure neutron beam polarization with 2x1 Neutron Spin Filter | A method to measure a beam polarization with the use of polarized 3He gas is
discussed. It is shown that special design of the Neutron Spin Filter cell
allows for a fast and accurate measurement. The accuracy of this method is
analyzed.
|
Discontinuity and Involutions on Countable Sets | For any infinite subset $X$ of the rationals and a subset $F \subseteq X$
which has no isolated points in $X$ we construct a function $f: X \to X$ such
that $f(f(x))=x$ for each $x\in X$ and $F $ is the set of discontinuity points
of $f$.
|
Optimal quantization for the pricing of swing options | In this paper, we investigate a numerical algorithm for the pricing of swing
options, relying on the so-called optimal quantization method. The numerical
procedure is described in details and numerous simulations are provided to
assert its efficiency. In particular, we carry out a comparison with the
Longstaff-Schwartz algorithm.
|
Extremal metrics on Hartogs domains | An $n$-dimensional Hartogs domain $D_F$ with strongly pseudoconvex boundary
can be equipped with a natural \K metric $g_F$. In this paper we prove that if
$g_F$ is an extremal \K metric then $(D_F, g_F)$ is biholomorphically isometric
to the $n$-dimensional complex hyperbolic space.
|
Parallelized approximation algorithms for minimum routing cost spanning
trees | We parallelize several previously proposed algorithms for the minimum routing
cost spanning tree problem and some related problems.
|
An efficient method for calculation of cooling in Lagrange computational
gas dynamics | A new method for computation of gas cooling for Lagrange approach is
suggested. The method is based on precalculation of cooling law for known
cooling function. Unlike implicit methods, this method is very efficient, it is
an one-step method which is even more accurate than implicit methods of the
same order.
|
Elementary transformation analysis for Array-OL | Array-OL is a high-level specification language dedicated to the definition
of intensive signal processing applications. Several tools exist for
implementing an Array-OL specification as a data parallel program. While
Array-OL can be used directly, it is often convenient to be able to deduce part
of the specification from a sequential version of the application. This paper
proposes such an analysis and examines its feasibility and its limits.
|
Heavy ion physics with the ALICE experiment at LHC | ALICE is the experiment at the LHC collider at CERN dedicated to heavy ion
physics. In this report, the ALICE detector will be presented, together with
its expected performance as far as some selected physics topics are concerned.
|
Monogamy of entanglement as a necessary and sufficient condition for
safe QKD in any physical theory | We show that the monogamy of entanglement is a sufficient phenomenon in every
physical theory, if the quantum key distribution is to be safe on the grounds
of such theory. To do so we present the QKD protocol that is safe in any
physical theory under the assumption of the monogamous entanglement only. The
necessity of this condition is also discussed.
|
Gerby Localization, Z_3-Hodge Integrals and the GW Theory of C^3/Z_3 | We exhibit a set of recursive relations that completely determine all
equivariant Gromov-Witten invariants of the quotient orbifold C^3/Z_3. We
interpret such invariants as G-Hodge Integrals, and produce relations among
them via Atiyah-Bott localization on moduli spaces of twisted stable maps to
gerbes over the projective line.
|
Quantum cohomology of [C^N/\mu_r] | We give a construction of the moduli space of stable maps to the classifying
stack B\mu_r of a cyclic group by a sequence of r-th root constructions on
M_{0, n}. We prove a closed formula for the total Chern class of
\mu_r-eigenspaces of the Hodge bundle, and thus of the obstruction bundle of
the genus zero Gromov-Witten theory of stacks of the form [C^N/\mu_r].
We deduce linear recursions for all genus-zero Gromov-Witten invariants.
|
Local dynamics for fibered holomorphic transformations | Fibered holomorphic dynamics are skew-product transformations over an
irrational rotation, whose fibers are holomorphic functions. In this paper we
study such a dynamics on a neighborhood of an invariant curve. We obtain some
results analogous to the results in the non fibered case.
|
Sequential mechanism design | In the customary VCG (Vickrey-Clarke-Groves) mechanism truth-telling is a
dominant strategy. In this paper we study the sequential VCG mechanism and show
that other dominant strategies may then exist. We illustrate how this fact can
be used to minimize taxes using examples concerned with Clarke tax and public
projects.
|
Note on exponential families of distributions | We show that an arbitrary probability distribution can be represented in
exponential form. In physical contexts, this implies that the equilibrium
distribution of any classical or quantum dynamical system is expressible in
grand canonical form.
|
Progress in Lattice QCD at finite temperature | I review recent developements in lattice QCD at finite temperature, including
the determination of the transition temperature T_c, equation of state and
diffenet static screening lengths. The lattice data suggest that at
temperatures above 1.5T_c the quark gluon plasma can be considered as gas
consisting of quarks and gluons.
|
Limits of Hypergraphs, Removal and Regularity Lemmas. A Non-standard
Approach | We study the integral and measure theory of the ultraproduct of finite sets.
As a main application we construct limit objects for hypergraph sequences. We
give a new proof for the Hypergraph Removal Lemma and the Hypergraph Regularity
Lemma.
|
Rational functions with linear relations | We find all polynomials f,g,h over a field K such that g and h are linear and
f(g(x))=h(f(x)). We also solve the same problem for rational functions f,g,h,
in case the field K is algebraically closed.
|
The Gorenstein Colength of an Artinian Local Ring | In this paper, we make the notion of approximating an Artinian local ring by
a Gorenstein Artin local ring precise using the concept of Gorenstein colength.
We also answer the question as to when the Gorenstein colength is at most two.
|
Conference Summary: The Central Engine of Active Galactic Nuclei | The 2006 meeting in Xi'an on the Central Engine of Active Galactic Nuclei
covered the enormous and continuously expanding area of AGN research, from
theory to the most sophisticated observations and from gamma-ray energies to
long radio wavelengths. This short summary gives some, but definitely not all,
highlights and new results presented by the participants.
|
Forward hadron production in high energy pA collisions: from RHIC to LHC | We present a calculation of Pi, D and B mesons production at RHIC and LHC
energies based upon the KKT model of gluon saturation. We discuss dependence of
the nuclear modification factor on rapidity and transverse momentum.
|
Charmonium at high temperature in two-flavor QCD | We compute charmonium spectral functions in 2-flavor QCD on anisotropic
lattices using the maximum entropy method. Our results suggest that the S-waves
(J/psi and eta_c) survive up to temperatures close to 2Tc, while the P-waves
(chi_c0 and chi_c1) melt away below 1.2Tc.
|
Annotated Bibliography of Some Papers on Combining Significances or
p-values | A question that comes up repeatedly is how to combine the results of two
experiments if all that is known is that one experiment had a n-sigma effect
and another experiment had a m-sigma effect. This question is not well-posed:
depending on what additional assumptions are made, the preferred answer is
different. The note lists some of the more prominent papers on the topic, with
some brief comments and excerpts.
|
Real interpolation of Sobolev spaces | We prove that $W^{1}_{p}$ is an interpolation space between $W^{1}_{p_{1}}$
and $W^{1}_{p_{2}}$ for $p>q_{0}$ and $1\leq p_{1}<p<p_{2}\leq \infty$ on some
classes of manifolds and general metric spaces, where $q_{0}$ depends on our
hypotheses.
|
Loop Quantum Gravity: Four Recent Advances and a Dozen Frequently Asked
Questions | As per organizers' request, my talk at the 11th Marcel Grossmann Conference
consisted of two parts. In the first, I illustrated recent advances in loop
quantum gravity through examples. In the second, I presented an overall
assessment of the status of the program by addressing some frequently asked
questions. This account is addressed primarily to researchers outside the loop
quantum gravity community.
|
The bang of a white hole in the early universe from a 6D vacuum state:
Origin of astrophysical spectrum | Using a previously introduced model in which the expansion of the universe is
driven by a single scalar field subject to gravitational attraction induced by
a white hole during the expansion (from a 6D vacuum state), we study the origin
of squared inflaton fluctuations spectrum on astrophysical scales.
|
The Answer is Blowing in the Wind | A 'News & Views' article -- no abstract.
|
Chaos and complexity in astrophysics | Methods and techniques of the theory of nonlinear dynamical systems and
patterns can be useful in astrophysical applications. Some works on the
subjects of dynamical astronomy, stellar pulsation and variability, as well as
spatial complexity in extended systems, in which such approaches have already
been utilized, are reviewed. Prospects for future directions in applications of
this kind are outlined.
|
Quasi-normal modes for black hole solutions unknown in analytical form | We review the papers [1-3]. We discuss possibilities of studying the
quasi-normal modes of black holes that are not known in an analytical form.
Such black holes appear as solutions in various theoretical models and real
astrophysical approximations when one takes into account the black hole
neighborhood.
|
Some geometric features of Berry's phase | In this letter, we elaborate on the identification and construction of the
differential geometric elements underlying Berry's phase. Berry bundles are
built generally from the physical data of the quantum system under study. We
apply this construction to typical and recently investigated systems presenting
Berry's phase to explore their geometric features.
|
A note on De Concini and Procesi's curious identity | We give a short, case-free and combinatorial proof of de Concini and
Procesi's formula for the volume of the simplicial cone spanned by the simple
roots of any finite root system. The argument presented here also extends their
formula to include the non-crystallographic root systems.
|
Real interpoaltion of Sobolev spaces associated to a weight | We study the interpolation property of Sobolev spaces of order 1 denoted by
$W^{1}_{p,V}$, arising from Schr\"{o}dinger operators with positive potential.
We show that for $1\leq p_1<p<p_2<q_{0}$ with $p>s_0$, $W^{1}_{p,V}$ is a real
interpolation space between $W_{p_1,V}^{1}$ and $W_{p_2,V}^{1}$ on some classes
of manifolds and Lie groups. The constants $s_{0}, q_{0}$ depend on our
hypotheses.
|
Bell Inequality Based on Peres-Horodecki Criterion | We established a physically utilizable Bell inequality based on the
Peres-Horodecki criterion. The new quadratic probabilistic Bell inequality
naturally provides us a necessary and sufficient way to test all entangled
two-qubit or qubit-qutrit states including the Werner states and the maximally
entangled mixed states.
|
Measurements of the observed cross sections for $e^+e^- \to$ light
hadrons at $\sqrt{s}=$ 3.773 and 3.650 GeV | Using the data sets of 17.3 pb$^{-1}$ collected at $\sqrt{s}=$ 3.773 GeV and
6.5 pb$^{-1}$ collected at $\sqrt{s}=$ 3.650 GeV with the BESII detector at the
BEPC collider, we have measured the observed cross sections for 18 exclusive
light hadron final states produced in $e^+e^-$ annihilation at the two energy
points.
|
Extension of the Adler-Bobenko-Suris classification of integrable
lattice equations | The classification of lattice equations that are integrable in the sense of
higher-dimensional consistency is extended by allowing directed edges. We find
two cases that are not transformable via the 'admissible transformations' to
the lattice equations in the existing classification.
|
On Uniqueness of Boundary Blow-up Solutions of a Class of Nonlinear
Elliptic Equations | We study boundary blow-up solutions of semilinear elliptic equations
$Lu=u_+^p$ with $p>1$, or $Lu=e^{au}$ with $a>0$, where $L$ is a second order
elliptic operator with measurable coefficients. Several uniqueness theorems and
an existence theorem are obtained.
|
|V_{ub}| from the Spectrum of B->pi e nu | I discuss the results for $|V_{ub}|f_+(0)$ and $|V_{ub}|$ obtained from the
spectrum of $B\to\pi e \nu$ and the form factor $f_+(q^2)$ from QCD sum rules
on the light-cone and unquenched lattice calculations; the shape of $f_+(q^2)$
is fixed from experimental data.
|
Anisotropic spin splitting of the electron ground state in InAs quantum
dots | Photoinduced circular dichroism experiments in an oblique magnetic field
allow measurements of Larmor precession frequencies, and so give a precise
determination of the electron Lande g factor and its anisotropy in
self-assembled InAs/GaAs quantum dots emitting at 1.32 eV. In good agreement
with recent theoretical results, we measure g perp= 0.397 +_ 0.003 and g par =
0.18 +- 0.02.
|
Withrawn paper | This paper has been withdrawn by the authors due to some fatal errors in the
analysis.
|
On randomized stopping | A general result on the method of randomized stopping is proved. It is
applied to optimal stopping of controlled diffusion processes with unbounded
coefficients to reduce it to an optimal control problem without stopping. This
is motivated by recent results of Krylov on numerical solutions to the Bellman
equation.
|
Near-Extreme Black Holes and the Universal Relaxation Bound | A fundamental bound on the relaxation time \tau of a perturbed
thermodynamical system has recently been derived, \tau \geq \hbar/\pi T, where
$T$ is the system's temperature. We demonstrate analytically that black holes
saturate this bound in the extremal limit and for large values of the azimuthal
number m of the perturbation field.
|
Stability of associated primes of monomial ideals | Let $I$ be a monomial ideal of a polynomial ring $R$. In this paper we
determine a number $B$ such that $\Ass (I^n/I^{n+1}) = \Ass (I^{B}/I^{B+1})$
for all $n\geq B$.
|
New Physics with Tagged Forward Protons at the LHC | The addition of forward proton detectors to LHC experiments will
significantly enlarge the potential for studying New Physics. A topical example
is Higgs production by the central exclusive diffractive process, pp -> p+H+p.
We discuss the exclusive production of Higgs bosons in both the SM and MSSM.
Special attention is paid to the backgrounds to the H -> bbbar signal.
|
Cadlag curves of SLE driven by Levy processes | Schramm Loewner Evolutions (SLE) are random increasing hulls defined through
the Loewner equation driven by Brownian motion. It is known that the increasing
hulls are generated by continuous curves. When the driving process is of the
form \sqrt{\kappa} B+\theta^{1/\alpha}S for a Brownian motion B and a symmetric
\alpha-stable process S with \kappa not equal to 4 and 8, we prove that the
corresponding increasing hulls are generated by Cadlag curves.
|
The orbifold transform and its applications | We discuss the notion of the orbifold transform, and illustrate it on simple
examples. The basic properties of the transform are presented, including
transitivity and the exponential formula for symmetric products. The connection
with the theory of permutation orbifolds is addressed, and the general results
illustrated on the example of torus partition functions.
|
A Curvature Principle for the interaction between universes | We propose a Curvature Principle to describe the dynamics of interacting
universes in a multi-universe scenario and show, in the context of a simplified
model, how interaction drives the cosmological constant of one of the universes
toward a vanishingly small value. We also conjecture on how the proposed
Curvature Principle suggests a solution for the entropy paradox of a universe
where the cosmological constant vanishes.
|
On the realignment criterion and beyond | The content of this paper is now available as part of arXiv:0802.2019
|
Boundary Conformal Field Theory and Ribbon Graphs: a tool for
open/closed string dualities | We construct and fully characterize a scalar boundary conformal field theory
on a triangulated Riemann surface. The results are analyzed from a string
theory perspective as tools to deal with open/closed string dualities.
|
Precise Charm and Bottom quark masses | New data for the total cross section sigma(e^+e^- --> hadrons) in the charm
and bottom threshold region are combined with an improved theoretical analysis,
which includes recent four-loop calculations, to determine the short distance
\bar{MS} charm and bottom quark masses. The final result for the
\bar{MS}-masses, m_c(3 GeV)=0.986(13) GeV and m_b(10 GeV)=3.609(25) GeV is
consistent with but significantly more precise than a similar previous study.
|
An elementary proof of the convergence of Ricci flow on compact surfaces | This paper has been withdrawn by the author for further modification.
|
On the motive of certain subvarieties of fixed flags | We compute de Chow motive of certain subvarieties of the flags manifold and
show that it is an Artin motive.
|
The status of the heavy quark systems | We review various inequalities on the order and the spacing of energy levels,
wave function at the origin, etc... which were obtained since 1977 in the
framework of the Schrodinger equation and applied to quarkonium and also to
muonic atoms and alcaline atoms. We also present a fit of mesons and baryons
made of b, c, s quarks and antiquarks, keeping the 1981 parameters and
comparing with present experimental data.
|
A Three-Flavor AdS/QCD Model with a Back-Reacted Geometry | A fully back-reaction geometry model of AdS/QCD including the strange quark
is described. We find that with the inclusion of the strange quark the impact
on the metric is very small and the final predictions are changed only
negligibly.
|
Periodic orbits in the case of a zero eigenvalue | We will show that if a dynamical system has enough constants of motion then a
Moser-Weinstein type theorem can be applied for proving the existence of
periodic orbits in the case when the linearized system is degenerate.
|
Lasso type classifiers with a reject option | We consider the problem of binary classification where one can, for a
particular cost, choose not to classify an observation. We present a simple
proof for the oracle inequality for the excess risk of structural risk
minimizers using a lasso type penalty.
|
The issue of photons in dielectrics: Hamiltonian viewpoint | The definition of the photon in the vacuum of general relativity provided by
Kermack et al. and by Synge is extended to nondispersive, nonhomogeneous,
isotropic dielectrics in arbitrary motion by Hamiltonian methods that rely on
Gordon's effective metric. By these methods the old dilemma, whether the
momentum-energy vector of the photon in dielectrics is timelike or spacelike in
character, is shown to reappear under a novel guise.
|
Coordinate Bethe Ansatz for the String S-Matrix | We use the coordinate Bethe ansatz approach to derive the nested Bethe
equations corresponding to the recently found S-matrix for strings in AdS5 x
S5, compatible with centrally extended su(2|2) symmetry.
|
Energy protection arguments fail in the interaction picture | Spin Hamiltonians with degenerate ground states are one potential system for
the storage of quantum information at low temperatures. Trapped ions can be
used to simulate the dynamics of these Hamiltonians, but the
coherence-preserving properties will be lost. This illustrates that a quantum
simulation performed in an interaction frame will not thermalize with its
environment.
|
Measurement of the gluon polarisation at COMPASS | COMPASS experiment measurements of the gluon polarisation in nucleon,
DeltaG/G are reviewed. Two different approaches based on tagging the Photon
Gluon Fusion process are described. They rely on the open charm meson or
high-p_T hadron pairs detection.
|
Bekenstein Bound and Spectral Geometry | In this letter it is proposed to study the Bekenstein's $\xi(4)$ calculation
of the $S/E$ bound for more general geometries. It is argued that, using some
relations among eigenvalues obtained in the context of Spectral Geometry, it is
possible to estimate $\xi(4)$ without an exact analytical knowledge of the
spectrum. Finally it is claimed that isospectrality can define a class of
domains with the same ratio $S/E$.
|
Singular link Floer homology | We define a grid presentation for singular links i.e. links with a finite
number of rigid transverse double points. Then we use it to generalize link
Floer homology to singular links. Besides the consistency of its definition, we
prove that this homology is acyclic under some conditions which naturally make
its Euler characteristic vanish.
|
The integrals in Gradshteyn and Ryzhik. Part 5: Some trigonometric
integrals | We present evalauations and provide proofs of definite integrals involving
the function x^p cos^n x. These formulae are generalizations of 3.761.11 and
3.822.1, among others, in the classical table of integrals by I. S. Gradshteyn
and I. M. Ryzhik.
|
Torsion units in integral group ring of Higman-Sims simple group | Using the Luthar-Passi method, we investigate the classical Zassenhaus
conjecture for the normalized unit group of the integral group ring of the
Higman-Sims simple sporadic group HS. As a consequence, we confirm the
Kimmerle's conjecture on prime graphs for this sporadic group.
|
Observing the evolution of a quantum system that does not evolve | This article deals with the problem of gathering information on the time
evolution of a single metastable quantum system whose evolution is impeded by
the quantum Zeno effect. It has been found it is in principle possible to
obtain some information on the time evolution and, depending on the specific
system, even to measure its average decay rate, even if the system does not
undergo any evolution at all.
|
Misere quotients for impartial games: Supplementary material | We provide supplementary appendices to the paper Misere quotients for
impartial games. These include detailed solutions to many of the octal games
discussed in the paper, and descriptions of the algorithms used to compute most
of our solutions.
|
The Nahm transform for calorons | In this paper, we complete the proof of an equivalence given by Nye and
Singer of the equivalence between calorons (instantons on $S^1\times R^3$) and
solutions to Nahm's equations over the circle, both satisfying appropriate
boundary conditions. Many of the key ingredients are provided by a third way of
encoding the same data which involves twistors and complex geometry.
|
Accurate backgrounds to Higgs production at the LHC | Corrections of 10-30% for backgrounds to the H --> WW --> l^+l^-\sla{p}_T
search in vector boson and gluon fusion at the LHC are reviewed to make the
case for precise and accurate theoretical background predictions.
|
GRB970228 as a prototype for short GRBs with afterglow | GRB970228 is analyzed as a prototype to understand the relative role of short
GRBs and their associated afterglows, recently observed by Swift and HETE-II.
Detailed theoretical computation of the GRB970228 light curves in selected
energy bands are presented and compared with observational BeppoSAX data.
|
Theoretical interpretation of GRB 011121 | GRB011121 is analyzed as a prototype to understand the ``flares'' recently
observed by Swift in the afterglow of many GRB sources. Detailed theoretical
computation of the GRB011121 light curves in selected energy bands are
presented and compared and contrasted with observational BeppoSAX data.
|
Generalized Morse and Poschl-Teller potentials : The connection via
Schrodinger equation | We present here a systematic and unified treatment to connect the Schrodinger
equation corresponding to generalized Morse and Poschl-Teller potentials. We
then show that the wave functions and generalized potentials are linked through
the Fourier and Hankel transforms, respectively.
|
A modularity test for elliptic mirror symmetry | In this note a prediction of an algebraic mirror construction is checked for
elliptic curves of Brieskorn-Pham type via number theoretic methods. It is
shown that the modular forms associated to the Hasse-Weil L-series of mirror
pairs of such curves are identical.
|
Higher-order Threshold Corrections for Single Top Quark Production | I discuss single top quark production at the Tevatron and the LHC. The cross
section, including soft-gluon threshold corrections through NNNLO, is presented
for each partonic channel. The higher-order corrections provide significant
contributions to the single top cross sections at both colliders.
|
Charm and charmonium spectroscopy at B-factories | We report on most recent Charm and Charmonium spectroscopy results from the
B-factories
|
A note on vacuum energy from the de Sitter spectrum | It is shown that a well-known relation between entropy of a system and its
energy spectrum being applied to the early universe determines the present
vacuum energy and the time scale on which this energy can manifest itself.
Given the present vacuum energy, the relation imposes a constraint on the
initial inflationary state.
|
Heisenberg limited Sagnac interferometry | We show how the entangled photons produced in parametric down conversion can
be used to improve the sensitivity of a Sagnac interferometer. Two-photon and
four-photon coincidences increases the sensitivity by a factor of two and four
respectively. Our results apply to sources with arbitrary pumping and squeezing
parameters.
|
General solution of overdamped Josephson junction equation in the case
of phase-lock | The first order nonlinear ODE d phi(t)/d t + sin phi(t)=B+A cos(omega t),
(A,B,omega are real constants) is investigated. Its general solution is derived
in the case of the choice of parameters ensuring the phase-lock mode. It is
represented in terms of Floquet solution of double confluent Heun equation.
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Characterization of rank two locally nilpotent derivations in dimension
three | In this paper we give an algorithmic characterization of rank two locally
nilpotent derivations in dimension three. Together with an algorithm for
computing the plinth ideal, this gives a method for computing the rank of a
locally nilpotent derivation in dimension three.
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Triangulable locally nilpotent derivations in dimension three | In this paper we give an algorithm to recognize triangulable locally
nilpotent derivations in dimension three. In case the given derivation is
triangulable, our method produces a coordinate system in which it exhibits a
triangular form.
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Frequency Windows of Absolute Negative Conductance in Josephson
Junctions | We report on anomalous conductance in a resistively and capacitively shunted
Josephson junction which is simultaneously driven by ac and dc currents. The
dependence of the voltage across the junction on the frequency of the ac
current shows windows of absolute negative conductance regimes, i.e. for a
positive (negative) dc current, the voltage is negative (positive).
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Cantor Singular Continuous Spectrum for Operators Along Interval
Exchange Transformations | It is shown that Schroedinger operators, with potentials along the shift
embedding of Lebesgue almost every interval exchange transformations, have
Cantor spectrum of measure zero and pure singular continuous for Lebesgue
almost all points of the interval.
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Observations of Galactic Gamma-Ray Sources with H.E.S.S | H.E.S.S. results from the first three years of nominal operation are
presented. Among the many exciting measurements that have been made, most
gamma-ray sources are of Galactic origin. I will concentrate here on an
overview of Galactic observations and summarise and discuss observations of
selected objects of the different source types.
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