Date: Mon, 11 Jul 11 00:06:40 GMT
Subject: math daily 70 new + 11 crosses received

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arXiv:1107.1502
Date: Thu, 7 Jul 2011 20:02:43 GMT   (45kb)

Title: Normal systems over ANR's, rigid embeddings and nonseparable absorbing
  sets
Authors: Piotr Niemiec
Categories: math.GN
Comments: 26 pages
MSC-class: 54C55, 57N20
\\
  Most of results of Bestvina and Mogilski [\textit{Characterizing certain
incomplete infinite-dimensional absolute retracts}, Michigan Math. J.
\textbf{33} (1986), 291--313] on strong $Z$-sets in ANR's and absorbing sets is
generalized to nonseparable case. It is shown that if an ANR $X$ is locally
homotopy dense embeddable in infinite-dimensional Hilbert manifolds and $w(U) =
w(X)$ (where `$w$' is the topological weight) for each open nonempty subset $U$
of $X$,then $X$ itself is homotopy dense embeddable in a Hilbert manifold. It
is also demonstrated that whenever $X$ is an AR, its weak product $W(X,*) =
\{(x_n)_{n=1}^{\infty} \in X^{\omega}:\ x_n = * \textup{for almost all} n\}$ is
homeomorphic to a pre-Hilbert space $E$ with $E \cong \Sigma E$. An intrinsic
characterization of manifolds modelled on such pre-Hilbert spaces is given.
\\ ( http://arxiv.org/abs/1107.1502 ,  45kb)
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arXiv:1107.1505
Date: Thu, 7 Jul 2011 20:08:34 GMT   (39kb)

Title: Norm closures of orbits of bounded operators
Authors: Piotr Niemiec
Categories: math.FA
Comments: 19 pages
MSC-class: 47A53, 47A55
\\
  To every bounded linear operator $A$ between Hilbert spaces $\mathcal{H}$ and
$\mathcal{K}$ three cardinals $\iota_r(A)$, $\iota_i(A)$ and $\iota_f(A)$ and a
binary number $\iota_b(A)$ are assigned in terms of which the descriptions of
the norm closures of the orbits $\{G A L^{-1}:\ L \in \mathcal{G}_1,\ G \in
\mathcal{G}_2\}$ are given for $\mathcal{G}_1$ and $\mathcal{G}_2$ (chosen
independently) being the trivial group, the unitary group or the group of all
invertible operators on $\mathcal{H}$ and $\mathcal{K}$, respectively.
\\ ( http://arxiv.org/abs/1107.1505 ,  39kb)
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arXiv:1107.1506
Date: Thu, 7 Jul 2011 20:08:58 GMT   (12kb)

Title: On representations of Clifford algebras of ternary cubic forms
Authors: Emre Coskun, Rajesh S. Kulkarni and Yusuf Mustopa
Categories: math.RA math.AG
Comments: 9 pages, to appear in proceedings for the conference "New Trends in
  Noncommutative Algebra: A Conference in Honor of Ken Goodearl's 65th
  Birthday"
MSC-class: 16G50, 14J60
\\
  In this article, we provide an overview of a one-to-one correspondence
between representations of the generalized Clifford algebra $C_f$ of a ternary
cubic form $f$ and certain vector bundles (called Ulrich bundles) on a cubic
surface $X$. We study general properties of Ulrich bundles, and using a recent
classification of Casanellas and Hartshorne, deduce the existence of
irreducible representations of $C_f$ of every possible dimension.
\\ ( http://arxiv.org/abs/1107.1506 ,  12kb)
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arXiv:1107.1508
Date: Thu, 7 Jul 2011 20:12:05 GMT   (29kb)

Title: A note on ANR's
Authors: Piotr Niemiec
Categories: math.GN
Comments: 8 pages
MSC-class: Primary 55M15, 54C55, Secondary 54E40, 54E50
\\
  It is shown that if for a complete metric space $(X,d)$ there is a constant
$\epsilon > 0$ such that the intersection $\bigcap_{j=1}^n B_d(x_j,r_j)$ of
open balls is nonempty for every finite system $x_1,...,x_n \in X$ of centers
and a corresponding system of radii $r_1,...,r_n > 0$ such that $d(x_j,x_k)
\leqsl \epsilon$ and $d(x_j,x_k) < r_j + r_k$ ($j,k = 1,...,n$), then $X$ is an
ANR; and if in the above one may put $\epsilon = \infty$, the space $X$ is an
AR. A certain criterion for an incomplete metric space to be an A(N)R is
presented.
\\ ( http://arxiv.org/abs/1107.1508 ,  29kb)
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arXiv:1107.1510
Date: Thu, 7 Jul 2011 20:16:19 GMT   (26kb)

Title: Problem with almost everywhere equality
Authors: Piotr Niemiec
Categories: math.GN
Comments: 4 pages
MSC-class: Primary 28A20, Secondary 28A05
\\
  A topological space $Y$ is said to have (AEEP) if the following condition is
fulfilled. Whenever $(X,\mathfrak{M})$ is a measurable space and $f, g: X \to
Y$ are two measurable functions, then the set $\Delta(f,g) = \{x \in X:\ f(x) =
g(x)\}$ is a member of $\mathfrak{M}$. It is shown that a metrizable space $Y$
has (AEEP) iff the cardinality of $Y$ is no greater than $2^{\aleph_0}$.
\\ ( http://arxiv.org/abs/1107.1510 ,  26kb)
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arXiv:1107.1512
Date: Thu, 7 Jul 2011 20:21:28 GMT   (32kb)

Title: Borel structure of the spectrum of a closed operator
Authors: Piotr Niemiec
Categories: math.FA math.SP
Comments: 11 pages
MSC-class: Primary 47A10, Secondary 54H05, 28A05
\\
  For a linear operator $T$ in a Banach space let $\sigma_p(T)$ denote the
point spectrum of $T$, $\sigma_{p[n]}(T)$ for finite $n > 0$ be the set of all
$\lambda \in \sigma_p(T)$ such that $\dim \ker (T - \lambda) = n$ and let
$\sigma_{p[\infty]}(T)$ be the set of all $\lambda \in \sigma_p(T)$ for which
$\ker (T - \lambda)$ is infinite-dimensional. It is shown that $\sigma_p(T)$ is
$\mathcal{F}_{\sigma}$, $\sigma_{p[\infty]}(T)$ is $\mathcal{F}_{\sigma\delta}$
and for each finite $n$ the set $\sigma_{p[n]}(T)$ is the intersection of an
$\mathcal{F}_{\sigma}$ and a $\mathcal{G}_{\delta}$ set provided $T$ is
closable and the domain of $T$ is separable and weakly $\sigma$-compact. For
closed densely defined operators in a separable Hilbert space $\mathcal{H}$
more detailed decomposition of the spectra is done and the algebra of all
bounded linear operators on $\mathcal{H}$ is decomposed into Borel parts. In
particular, it is shown that the set of all closed range operators on
$\mathcal{H}$ is Borel.
\\ ( http://arxiv.org/abs/1107.1512 ,  32kb)
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arXiv:1107.1513
Date: Thu, 7 Jul 2011 20:28:41 GMT   (58kb)

Title: Robustness of Two Simple Rules for the Evolution of Cooperation on
  Regular Graphs
Authors: Yu-Ting Chen
Categories: math.PR
\\
  We study two simple rules on finite graphs for the death-birth updating and
the imitation updating discovered by Ohtsuki, Hauert, Lieberman, and Nowak
[\emph{Nature} {\bf 441} (2006) 502-505]. Each rule consists a payoff-ratio
cutoff point for the magnitude of fixation probabilities of the underlying
evolutionary game between cooperators and defectors. We view the Markov chains
associated to the two updating mechanisms as voter model perturbations. Then we
present a first-order approximation of fixation probabilities for general voter
model perturbations on finite graphs under weak selection in terms of the voter
model fixation probabilities. In the context of regular graphs, the fixation
probabilities of cooperators distributed as certain uniform distributions have
algebraically explicit first-order approximations. These approximations lead to
a rigorous proof that both of the rules of Ohtsuki et al. are valid and are
robust.
\\ ( http://arxiv.org/abs/1107.1513 ,  58kb)
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arXiv:1107.1520
Date: Thu, 7 Jul 2011 21:03:06 GMT   (21kb)

Title: Lipschitz Games
Authors: Yaron Azrieli and Eran Shmaya
Categories: math.CO cs.GT
Comments: 17 papers
MSC-class: 91A10, 05D40
\\
  The Lipschitz constant of a finite normal-form game is the maximal change in
some player's payoff when a single opponent changes his strategy. We prove that
games with small Lipschitz constant admit pure {\epsilon}-equilibria, and
pinpoint the maximal Lipschitz constant that is sufficient to imply existence
of pure {\epsilon}-equilibrium as a function of the number of players in the
game and the number of strategies of each player. Our proofs use the
probabilistic method.
\\ ( http://arxiv.org/abs/1107.1520 ,  21kb)
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arXiv:1107.1522
Date: Thu, 7 Jul 2011 21:16:29 GMT   (25kb)

Title: Pfaffian quartic surfaces and representations of Clifford algebras
Authors: Emre Coskun, Rajesh S. Kulkarni and Yusuf Mustopa
Categories: math.AG math.RA
Comments: This paper contains a proof of the main result claimed in the
  erroneous preprint arXiv:1103.0529. We also extend this result to all smooth
  quartic surfaces
MSC-class: 14J60, 14J28, 16G50
\\
  Given a nondegenerate ternary form $f=f(x_1,x_2,x_3)$ of degree 4 over an
algebraically closed field of characteristic zero, we use the geometry of K3
surfaces and van den Bergh's correspondence between representations of the
generalized Clifford algebra $C_f$ associated to $f$ and Ulrich bundles on the
surface $X_f:=\{w^{4}=f(x_1,x_2,x_3)\} \subseteq \mathbb{P}^3$ to construct a
positive-dimensional family of irreducible representations of $C_f.$
  The main part of our construction, which is of independent interest, uses
recent work of Aprodu-Farkas on Green's Conjecture together with a result of
Basili on complete intersection curves in $\mathbb{P}^{3}$ to produce simple
Ulrich bundles of rank 2 on a smooth quartic surface $X \subseteq \mathbb{P}^3$
with determinant $\mathcal{O}_X(3).$ This implies that every smooth quartic
surface in $\mathbb{P}^3$ is the zerolocus of a linear Pfaffian, strengthening
a result of Beauville-Schreyer on general quartic surfaces.
\\ ( http://arxiv.org/abs/1107.1522 ,  25kb)
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arXiv:1107.1523
Date: Thu, 7 Jul 2011 21:17:28 GMT   (21kb)

Title: Invariant Measures with Bounded Variation Densities for Piecewise Area
  Preserving Maps
Authors: Yiwei Zhang and Congping Lin
Categories: math.DS
Comments: 19 pages
\\
  We investigate the properties of absolutely continuous invariant probability
measures (ACIPs) for piecewise area preserving maps (PAPs) on $\mathbb{R}^d$.
This class of maps unifies piecewise isometries (PWIs) and piecewise hyperbolic
maps where Lebesgue measure is locally preserved. In particular for PWIs, we
use a functional approach to explore the relationship between topological
transitivity and uniqueness of ACIPs, especially those measures with bounded
variation densities. Our results "partially" answer one of the fundamental
questions posed in \cite{Goetz03} - determine all invariant non-atomic
probability Borel measures in piecewise rotations. When reducing to interval
exchange transformations (IETs), we demonstrate that for non-uniquely ergodic
IETs with two or more ACIPs, these ACIPs have very irregular densities (namely
of unbounded variation and discontinuous everywhere) and intermingle with each
other.
\\ ( http://arxiv.org/abs/1107.1523 ,  21kb)
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arXiv:1107.1524
Date: Thu, 7 Jul 2011 21:20:59 GMT   (102kb)

Title: Khovanov Homology
Authors: Louis H. Kauffman
Categories: math.GT
Comments: 31 pages. 11 figures. LaTeX document
MSC-class: 57M25
\\
  This paper is an introduction to Khovanov homology.
\\ ( http://arxiv.org/abs/1107.1524 ,  102kb)
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arXiv:1107.1525
Date: Tue, 21 Jun 2011 22:55:02 GMT   (35kb)

Title: Accelerating Lossless Data Compression with GPUs
Authors: R. L. Cloud, M. L. Curry, H. L. Ward, A. Skjellum, P. Bangalore
Categories: cs.IT cs.GR cs.PF math.IT
Comments: peer reviewed and published in undergraduate research journal Inquiro
  in 2009 after Summer work in 2009
Journal-ref: Inquiro, Volume 3, 2009, p. 26 - 29
\\
  Huffman compression is a statistical, lossless, data compression algorithm
that compresses data by assigning variable length codes to symbols, with the
more frequently appearing symbols given shorter codes than the less. This work
is a modification of the Huffman algorithm which permits uncompressed data to
be decomposed into indepen- dently compressible and decompressible blocks,
allowing for concurrent compression and decompression on multiple processors.
We create implementations of this modified algorithm on a current NVIDIA GPU
using the CUDA API as well as on a current Intel chip and the performance
results are compared, showing favorable GPU performance for nearly all tests.
Lastly, we discuss the necessity for high performance data compression in
today's supercomputing ecosystem.
\\ ( http://arxiv.org/abs/1107.1525 ,  35kb)
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arXiv:1107.1528
Date: Thu, 7 Jul 2011 21:40:15 GMT   (5kb)

Title: Product decompositions in finite simple groups
Authors: Martin Liebeck, Nikolay Nikolov, Aner Shalev
Categories: math.GR
MSC-class: 20D40, 20D06
\\
  We propose a general conjecture on decompositions of finite simple groups as
products of conjugates of an arbitrary subset. We prove this conjecture for
bounded subsets of arbitrary finite simple groups, and for large subsets of
groups of Lie type of bounded rank. Some of our arguments apply recent advances
in the theory of growth in finite simple groups of Lie type, and provide a
variety of new product decompositions of these groups.
\\ ( http://arxiv.org/abs/1107.1528 ,  5kb)
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arXiv:1107.1529
Date: Thu, 7 Jul 2011 21:49:55 GMT   (11kb)

Title: Decoding of Matrix-Product Codes
Authors: Fernando Hernando and Diego Ruano
Categories: cs.IT math.IT
MSC-class: 94B05, 94B35
\\
  We propose a decoding algorithm for the $(u\mid u+v)$-construction that
decodes up to half of the minimum distance of the linear code. We extend this
algorithm for a class of matrix-product codes in two different ways. In some
cases, one can decode beyond the error correction capability of the code.
\\ ( http://arxiv.org/abs/1107.1529 ,  11kb)
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arXiv:1107.1532
Date: Thu, 7 Jul 2011 22:04:05 GMT   (39kb,D)

Title: SIR epidemics on a scale-free spatial nested modular network with a
  non-trivial threshold
Authors: Lorenzo Cecconi and Alberto Gandolfi
Categories: math.PR
Comments: 20 pages, 1 figure
MSC-class: 60K35, 92D30
\\
  We propose a class of random scale-free spatial networks with nested
community structures and analyze Reed-Frost epidemics with community related
independent transmissions. We show that the epidemic threshold may be trivial
or not depending on the relation among community sizes, distribution of the
number of communities and transmission rates
\\ ( http://arxiv.org/abs/1107.1532 ,  39kb)
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arXiv:1107.1533
Date: Thu, 7 Jul 2011 22:29:01 GMT   (7kb)

Title: Martingale Couplings and Bounds on the Tails of Probability
  Distributions
Authors: Kyle J. Luh and Nicholas Pippenger
Categories: math.PR math.ST stat.TH
Comments: i+7 pp
\\
  Hoeffding has shown that tail bounds on the distribution for sampling from a
finite population with replacement also apply to the corresponding cases of
sampling without replacement. (A special case of this result is that binomial
tail bounds apply to the corresponding hypergeometric tails.) We give a new
proof of Hoeffding's result by constructing a martingale coupling between the
sampling distributions. This construction is given by an explicit combinatorial
procedure involving balls and urns. We then apply this construction to create
martingale couplings between other pairs of sampling distributions, both
without replacement and with "surreplacement" (that is, sampling in which not
only is the sampled individual replaced, but some number of "copies" of that
individual are added to the population).
\\ ( http://arxiv.org/abs/1107.1533 ,  7kb)
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arXiv:1107.1535
Date: Thu, 7 Jul 2011 23:41:33 GMT   (150kb,D)

Title: Multilevel Polarization of Polar Codes Over Arbitrary Discrete
  Memoryless Channels
Authors: Aria G. Sahebi and S. Sandeep Pradhan
Categories: cs.IT math.IT
\\
  It is shown that the original construction of polar codes suffices to achieve
the symmetric capacity of discrete memoryless channels with arbitrary input
alphabet sizes. It is shown that in general, channel polarization happens in
several, rather than only two, levels so that the synthesized channels are
either useless, perfect or "partially perfect". Given a coset decomposition of
the input alphabet, there exists a corresponding partially perfect channel
whose outputs uniquely determine the coset where the channel input symbol
belongs to. By a slight modification of the encoding and decoding rules, it is
shown that perfect transmission of certain information letters over partially
perfect channels is possible. It is also shown through an example that polar
codes do not achieve the capacity of coset codes over arbitrary channels.
\\ ( http://arxiv.org/abs/1107.1535 ,  150kb)
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arXiv:1107.1536
Date: Thu, 7 Jul 2011 23:42:26 GMT   (5kb)

Title: The M/M/Infinity Service System with Ranked Servers in Heavy Traffic
Authors: Patrick Eschenfeldt, Ben Gross and Nicholas Pippenger
Categories: math.PR cs.PF
Comments: i+6 pp
MSC-class: 60K26, 90B22
\\
  We consider an M/M/Infinity service system in which an arriving customer is
served by the first idle server in an infinite sequence S_1, S_2, ... of
servers. We determine the first two terms in the asymptotic expansions of the
moments of L as lambda tends to infinity, where L is the index of the server
S_L serving a newly arriving customer in equilibrium, and lambda is the ratio
of the arrival rate to the service rate. The leading terms of the moments show
that L/lambda tends to a uniform distribution on [0,1].
\\ ( http://arxiv.org/abs/1107.1536 ,  5kb)
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arXiv:1107.1538
Date: Thu, 7 Jul 2011 23:55:55 GMT   (74kb)

Title: Singular foliations with trivial canonical class
Authors: Frank Loray, Jorge Vitorio Pereira, Frederic Touzet
Categories: math.AG math.CV math.DS
Comments: 68 pages
\\
  This paper is devoted to describe the structure of singular codimension one
foliations with numerically trivial canonical bundle on projective manifolds.
To achieve this goal we study the reduction modulo $p$ of foliations, describe
the structure of first integrals of (semi-)stable foliations with (negative)
zero canonical bundle, establish a criterium for uniruledness of projective
manifolds, and investigate the deformation of free morphisms along foliations.
This paper also contains a classification of the irreducible components of the
space of foliations with $K\mathcal F \le 0$ on Fano 3-folds with rank one
Picard group, and new information about the structure of codimension one
foliations on $\mathbb P^n$ of degree smaller than or equal to $2n-3$.
\\ ( http://arxiv.org/abs/1107.1538 ,  74kb)
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arXiv:1107.1539
Date: Thu, 7 Jul 2011 23:58:41 GMT   (13kb)

Title: Lie algebroid modules and representations up to homotopy
Authors: Rajan Amit Mehta
Categories: math.DG
MSC-class: 16E45, 53D17, 58A50
\\
  We explain how Lie algebroid modules in the sense of Vaintrob provide
geometric models for Lie algebroid representations up to homotopy.
Specifically, we show that there is a noncanonical way to obtain
representations up to homotopy from a given Lie algebroid module, and that any
two representations up to homotopy obtained in this way are equivalent in a
natural sense. This result extends the relationship between VB-algebroids and
2-term representations up to homotopy, as studied by Gracia-Saz and the author.
We also extend the construction of VB-algebroid characteristic classes to the
setting of Lie algebroid modules.
\\ ( http://arxiv.org/abs/1107.1539 ,  13kb)
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arXiv:1107.1541
Date: Fri, 8 Jul 2011 00:53:57 GMT   (286kb,D)

Title: Entropy of Schur-Weyl Measures
Authors: Sevak Mkrtchyan
Categories: math.RT math.CO math.PR
Comments: 45 pages, 10 Figures
MSC-class: 05D40, 05E10, 20C30, 60C05
\\
  Relative dimensions of isotypic components of N-th order tensor
representations of the symmetric group on n letters give a Plancherel-type
measure on the space of Young diagrams with n cells and at most N rows. It was
conjectured by G. Olshanski that dimensions of isotypic components of tensor
representations of finite symmetric groups, after appropriate normalization,
converge to a constant with respect to this family of Plancherel-type measures
in the limit when N/sqrt{n} converges to a constant. The main result of the
paper is the proof of this conjecture.
\\ ( http://arxiv.org/abs/1107.1541 ,  286kb)
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arXiv:1107.1543
Date: Fri, 8 Jul 2011 01:39:19 GMT   (22kb)

Title: Rational curves on the supersingular K3 surface with Artin invariant 1
  in characteristic 3
Authors: Toshiyuki Katsura, Shigeyuki Kondo
Categories: math.AG
Comments: 31 pages
\\
  We show the existence of 112 non-singular rational curves on the
supersingular K3 surface with Artin invariant 1 in characteristic 3 by several
ways. Using these rational curves, we have a $(16)_{10}$-configuration and a
$(280_{4}, 112_{10})$-configuration on the K3 surface. Moreover we study the
Picard lattice by using the theory of the Leech lattice. The 112 non-singular
rational curves correspond to 112 Leech roots.
\\ ( http://arxiv.org/abs/1107.1543 ,  22kb)
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arXiv:1107.1544
Date: Fri, 8 Jul 2011 01:43:00 GMT   (157kb,D)

Title: Cooperative Jamming for Secure Communications in MIMO Relay Networks
Authors: Jing Huang and A. Lee Swindlehurst
Categories: cs.IT math.IT
Comments: 30 pages, 7 figures, to appear in IEEE Transactions on Signal
  Processing
\\
  Secure communications can be impeded by eavesdroppers in conventional relay
systems. This paper proposes cooperative jamming strategies for two-hop relay
networks where the eavesdropper can wiretap the relay channels in both hops. In
these approaches, the normally inactive nodes in the relay network can be used
as cooperative jamming sources to confuse the eavesdropper. Linear precoding
schemes are investigated for two scenarios where single or multiple data
streams are transmitted via a decode-and-forward (DF) relay, under the
assumption that global channel state information (CSI) is available. For the
case of single data stream transmission, we derive closed-form jamming
beamformers and the corresponding optimal power allocation. Generalized
singular value decomposition (GSVD)-based secure relaying schemes are proposed
for the transmission of multiple data streams. The optimal power allocation is
found for the GSVD relaying scheme via geometric programming. Based on this
result, a GSVD-based cooperative jamming scheme is proposed that shows
significant improvement in terms of secrecy rate compared to the approach
without jamming. Furthermore, the case involving an eavesdropper with unknown
CSI is also investigated in this paper. Simulation results show that the
secrecy rate is dramatically increased when inactive nodes in the relay network
participate in cooperative jamming.
\\ ( http://arxiv.org/abs/1107.1544 ,  157kb)
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arXiv:1107.1563
Date: Fri, 8 Jul 2011 06:05:55 GMT   (777kb)

Title: Designing Nonlinear Turbo Codes with a Target Ones Density
Authors: Jiadong Wang, Thomas Courtade, Tsung-Yi Chen, Bike Xie and Richard
  Wesel
Categories: cs.IT math.IT
\\
  Certain binary asymmetric channels, such as Z-channels in which one of the
two crossover probabilities is zero, demand optimal ones densities different
from 50%. Some broadcast channels, such as broadcast binary symmetric channels
(BBSC) where each component channel is a binary symmetric channel, also require
a non-uniform input distribution due to the superposition coding scheme, which
is known to achieve the boundary of capacity region. This paper presents a
systematic technique for designing nonlinear turbo codes that are able to
support ones densities different from 50%. To demonstrate the effectiveness of
our design technique, we design and simulate nonlinear turbo codes for the
Z-channel and the BBSC. The best nonlinear turbo code is less than 0.02 bits
from capacity.
\\ ( http://arxiv.org/abs/1107.1563 ,  777kb)
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arXiv:1107.1571
Date: Fri, 8 Jul 2011 07:36:34 GMT   (1227kb)

Title: On ringing effects near jump discontinuities for periodic solutions to
  dispersive partial differential equations
Authors: Kenneth D. T.-R. McLaughlin and Nigel J. E. Pitt
Categories: math.AP
Comments: 22 pages, 10 figures
MSC-class: 35B40, 35B65, 35B05
\\
  We consider weak solutions to dispersive partial differential equations with
periodic boundary conditions and initial data with jump discontinuities. These
are already known to be continuous at irrational times and piecewise constant
at rational times; we show that as time approaches a rational value the
solution exhibits a ringing effect, with the characteristic overshoot of fixed
amplitude near the discontinuities. Furthermore this effect is the same whether
the sequence of times follows rational or irrational values.
\\ ( http://arxiv.org/abs/1107.1571 ,  1227kb)
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arXiv:1107.1572
Date: Fri, 8 Jul 2011 08:09:57 GMT   (12kb)

Title: On Hecke eigenvalues at primes of the form $[g(n)]$
Authors: Stephan Baier, Liangyi Zhao
Categories: math.NT
Comments: 13 pages
MSC-class: 11F11, 11F30, 11F60, 11L03, 11L07, 11L20
\\
  In this paper, we study the average of the Fourier coefficients of a
holomorphic cusp form for the full modular group at primes of the form
$[g(n)]$.
\\ ( http://arxiv.org/abs/1107.1572 ,  12kb)
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arXiv:1107.1580
Date: Fri, 8 Jul 2011 09:10:29 GMT   (141kb)

Title: Controller Synthesis for Robust Invariance of Polynomial Dynamical
  Systems using Linear Programming
Authors: Mohamed Amin Ben Sassi and Antoine Girard
Categories: math.OC cs.SY
\\
  In this paper, we consider a control synthesis problem for a class of
polynomial dynamical systems subject to bounded disturbances and with input
constraints. More precisely, we aim at synthesizing at the same time a
controller and an invariant set for the controlled system under all admissible
disturbances. We propose a computational method to solve this problem. Given a
candidate polyhedral invariant, we show that controller synthesis can be
formulated as an optimization problem involving polynomial cost functions over
bounded polytopes for which effective linear programming relaxations can be
obtained. Then, we propose an iterative approach to compute the controller and
the polyhedral invariant at once. Each iteration of the approach mainly
consists in solving two linear programs (one for the controller and one for the
invariant) and is thus computationally tractable. Finally, we show with several
examples the usefulness of our method in applications.
\\ ( http://arxiv.org/abs/1107.1580 ,  141kb)
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arXiv:1107.1584
Date: Fri, 8 Jul 2011 09:27:30 GMT   (146kb)

Title: Approximate Parametrization of Space Algebraic Curves
Authors: Sonia L. Rueda, Juana Sendra, J. Rafael Sendra
Categories: math.AG
MSC-class: 14H50
\\
  Given a non-rational real space curve and a tolerance $\epsilon>0$, we
present an algorithm to approximately parametrize the curve. The algorithm
checks whether a planar projection of the space curve is $\epsilon$-rational
and, in the affirmative case, generates a planar parametrization that is lifted
to an space parametrization. This output rational space curve is of the same
degree as the input curve, both have the same structure at infinity, and the
Hausdorff distance between them is always finite.
\\ ( http://arxiv.org/abs/1107.1584 ,  146kb)
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arXiv:1107.1594
Date: Fri, 8 Jul 2011 10:01:25 GMT   (1069kb,D)

Title: Turing instabilities in a mathematical model for signaling networks
Authors: Andreas R\"atz and Matthias R\"oger
Categories: math.AP q-bio.CB
MSC-class: 92C37, 35K57, 35Q92
\\
  GTPase molecules are important regulators in cells that continuously run
through an activation/deactivation and membrane-attachment/membrane-detachment
cycle. Activated GTPase is able to localize in parts of the membranes and to
induce cell polarity. As feedback loops contribute to the GTPase cycle and as
the coupling between membrane-bound and cytoplasmic processes introduces
different diffusion coefficients a Turing mechanism is a natural candidate for
this symmetry breaking. We formulate a mathematical model that couples a
reaction-diffusion system in the inner volume to a reaction-diffusion system on
the membrane via a flux condition and an attachment/detachment law at the
membrane. We present a reduction to a simpler non-local reaction-diffusion
model and perform a stability analysis and numerical simulations for this
reduction. Our model in principle does support Turing instabilities but only if
the lateral diffusion of inactivated GTPase is much faster than the diffusion
of activated GTPase.
\\ ( http://arxiv.org/abs/1107.1594 ,  1069kb)
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\\
arXiv:1107.1595
Date: Fri, 8 Jul 2011 10:01:42 GMT   (27kb)

Title: Global existence for the Euler-Maxwell system
Authors: Pierre Germain, Nader Masmoudi
Categories: math.AP
Comments: 33 pages
MSC-class: 35L03, 35L60, 35Q31, 35Q60, 37L50
\\
  The Euler-Maxwell system describes the evolution of a plasma when the
collisions are important enough that each species is in a hydrodynamic
equilibrium. In this paper we prove global existence of small solutions to this
system set in the whole three-dimensional space, by combining the space-time
resonance method, dispersive estimates, localization estimates and energy
estimates. An important novelty is that we can prove a very slow growth of high
derivatives even with a nonintegrable decay by reiterating the energy estimate.
\\ ( http://arxiv.org/abs/1107.1595 ,  27kb)
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\\
arXiv:1107.1600
Date: Fri, 8 Jul 2011 10:32:26 GMT   (103kb)

Title: On fuzzy syndrome hashing with LDPC coding
Authors: Marco Baldi, Marco Bianchi, Franco Chiaraluce, Joachim Rosenthal and
  Davide Schipani
Categories: cs.IT cs.CR math.IT
\\
  The last decades have seen a growing interest in hash functions that allow
some sort of tolerance, e.g. for the purpose of biometric authentication. Among
these, the syndrome fuzzy hashing construction allows to securely store
biometric data and to perform user authentication without the need of sharing
any secret key. This paper analyzes this model, showing that it offers a
suitable protection against information leakage and several advantages with
respect to similar solutions, such as the fuzzy commitment scheme. Furthermore,
the design and characterization of LDPC codes to be used for this purpose is
addressed.
\\ ( http://arxiv.org/abs/1107.1600 ,  103kb)
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\\
arXiv:1107.1603
Date: Fri, 8 Jul 2011 10:53:54 GMT   (15kb)

Title: Extrinsic hyperspheres in manifolds with special holonomy
Authors: Tillmann Jentsch, Andrei Moroianu And Uwe Semmelmann
Categories: math.DG
Comments: 12 pages
MSC-class: 53C26, 53C35, 53C10, 53C15
\\
  We describe extrinsic hyperspheres and totally geodesic hypersurfaces in
manifolds with special holonomy. In particular we prove the nonexistence of
extrinsic hyperspheres in quaternion-Kaehler manifolds. We develop a new
approach to extrinsic hyperspheres based on the classification of special
Killing forms.
\\ ( http://arxiv.org/abs/1107.1603 ,  15kb)
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\\
arXiv:1107.1607
Date: Fri, 8 Jul 2011 11:15:35 GMT   (32kb)

Title: Path properties and regularity of affine processes on general state
  spaces
Authors: Christa Cuchiero and Josef Teichmann
Categories: math.PR q-fin.GN
MSC-class: 60J25, 60G17
\\
  We provide a new proof for regularity of affine processes on general state
spaces by methods from the theory of Markovian semimartingales. On the way to
this result we also show that the definition of an affine process, namely as
stochastically continuous time-homogeneous Markov process with exponential
affine Fourier-Laplace transform, already implies the existence of a c\`adl\`ag
version. This was one of the last open issues in the fundaments of affine
processes.
\\ ( http://arxiv.org/abs/1107.1607 ,  32kb)
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\\
arXiv:1107.1609
Date: Fri, 8 Jul 2011 11:17:54 GMT   (21kb)

Title: Linear Complexity Lossy Compressor for Binary Redundant Memoryless
  Sources
Authors: Kazushi Mimura
Categories: cs.IT cond-mat.dis-nn math.IT
Comments: 4 pages, 1 figure
\\
  A lossy compression algorithm for binary redundant i.i.d. sources is
presented. The proposed scheme is based on sparse graph codes. By introducing a
nonlinear function, redundant memoryless sequences can be compressed. We
propose a linear complexity compressor based on the extended belief
propagation, into which an inertia term is heuristically introduced, and show
that it has near optimal performance for moderate blocklengths.
\\ ( http://arxiv.org/abs/1107.1609 ,  21kb)
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\\
arXiv:1107.1618
Date: Fri, 8 Jul 2011 12:20:23 GMT   (21kb)

Title: Spectral functions of products of selfadjoint operators
Authors: Tomas Ya. Azizov, Mikhail Denisov, Friedrich Philipp
Categories: math.SP
MSC-class: 47A11, 47B50
\\
  Given two possibly unbounded selfadjoint operators A and G such that the
resolvent sets of AG and GA are non-empty, it is shown that the operator AG has
a spectral function on IR with singularities if there exists a non-zero
polynomial p such that the symmetric operator Gp(AG) is non-negative. This
result generalizes a well-known theorem for definitizable operators in Krein
spaces.
\\ ( http://arxiv.org/abs/1107.1618 ,  21kb)
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\\
arXiv:1107.1627
Date: Fri, 8 Jul 2011 13:21:28 GMT   (1326kb)

Title: On Codes for Optimal Rebuilding Access
Authors: Zhiying Wang, Itzhak Tamo, Jehoshua Bruck
Categories: cs.IT cs.DC math.IT
Comments: Submitted to Allerton 2011
\\
  MDS (maximum distance separable) array codes are widely used in storage
systems due to their computationally efficient encoding and decoding
procedures. An MDS code with r redundancy nodes can correct any r erasures by
accessing (reading) all the remaining information in both the systematic nodes
and the parity (redundancy) nodes. However, in practice, a single erasure is
the most likely failure event; hence, a natural question is how much
information do we need to access in order to rebuild a single storage node? We
define the rebuilding ratio as the fraction of remaining information accessed
during the rebuilding of a single erasure. In our previous work we showed that
the optimal rebuilding ratio of 1/r is achievable (using our newly constructed
array codes) for the rebuilding of any systematic node, however, all the
information needs to be accessed for the rebuilding of the parity nodes.
Namely, constructing array codes with a rebuilding ratio of 1/r was left as an
open problem. In this paper, we solve this open problem and present array codes
that achieve the lower bound of 1/r for rebuilding any single systematic or
parity node.
\\ ( http://arxiv.org/abs/1107.1627 ,  1326kb)
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\\
arXiv:1107.1632
Date: Fri, 8 Jul 2011 13:47:03 GMT   (22kb)

Title: Growth behaviors in the range $e^{r^\alpha}$
Authors: J\'er\'emie Brieussel
Categories: math.GR
Comments: 23 pages, 2 figures
\\
  For every $\alpha \leq \beta$ in a left neighborhood $[\alpha_0,1]$ of 1, a
group $G(\alpha,\beta)$ is constructed, the growth function of which satisfies
$\limsup \frac{\log \log b_{G(\alpha,\beta)}(r)}{\log r}=\alpha$ and $\liminf
\frac{\log \log b_{G(\alpha,\beta)}(r)}{\log r}=\beta$. When $\alpha=\beta$,
this provides an explicit uncountable collection of groups with growth
functions strictly comparable. On the other hand, oscillation in the case
$\alpha < \beta$ explains the existence of groups with non comparable growth
functions. Some period exponents associated to the frequency of oscillation
provide new group invariants.
\\ ( http://arxiv.org/abs/1107.1632 ,  22kb)
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\\
arXiv:1107.1634
Date: Fri, 8 Jul 2011 13:51:18 GMT   (32kb)

Title: Arithmetic of 0-cycles on varieties defined over number fields
Authors: Yongqi Liang
Categories: math.AG math.NT
Comments: 21 pages, part of the main result appeared in an old version of the
  author's preprint (arXiv:1011.5995), the proof here is simplified
MSC-class: 14G25 (11G35, 14M22)
\\
  Let $X$ be a rationally connected algebraic variety, defined over a number
field $k$. We find a relation between the arithmetic of rational points on $X$
and the arithmetic of zero-cycles. More precisely, we consider the following
statements: (1) the Brauer-Manin obstruction is the only obstruction to weak
approximation for $K$-rational points on $X_K$ for all finite extensions $K/k$;
(2) the Brauer-Manin obstruction is the only obstruction to weak approximation
in some sense that we define for zero-cycles of degree 1 on $X_K$ for all
finite extensions $K/k$; (3) a certain sequence of local-global type for Chow
groups of 0-cycles on $X_K$ is exact for all finite extensions $K/k$. We prove
that (1) implies (2), and that (2) and (3) are equivalent. We also prove a
similar implication for the Hasse principle.
  As an application, we prove the exactness of the sequence mentioned above for
smooth compactifications of certain homogeneous spaces of linear algebraic
groups.
\\ ( http://arxiv.org/abs/1107.1634 ,  32kb)
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\\
arXiv:1107.1636
Date: Fri, 8 Jul 2011 14:02:46 GMT   (12kb)

Title: An analytic approach to the stratified Morse inequalities for complex
  cones
Authors: Ursula Ludwig
Categories: math.DG
Comments: 12 pages
\\
  In a previous article the author extended the Witten deformation to singular
spaces with cone-like singularities and to a class of Morse functions called
admissible Morse functions. The method applies in particular to complex cones
and stratified Morse functions in the sense of the theory developed by Goresky
and MacPherson. It is well-known from stratified Morse theory that the singular
points of the complex cone contribute to the stratified Morse inequalities in
middle degree only. In this article an analytic proof of this fact is given.
\\ ( http://arxiv.org/abs/1107.1636 ,  12kb)
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\\
arXiv:1107.1638
Date: Fri, 8 Jul 2011 14:10:49 GMT   (3557kb,D)

Title: Weighted algorithms for compressed sensing and matrix completion
Authors: St\'ephane Ga\"iffas and Guillaume Lecu\'e
Categories: cs.IT math.IT math.ST stat.TH
\\
  This paper is about iteratively reweighted basis-pursuit algorithms for
compressed sensing and matrix completion problems. In a first part, we give a
theoretical explanation of the fact that reweighted basis pursuit can improve a
lot upon basis pursuit for exact recovery in compressed sensing. We exhibit a
condition that links the accuracy of the weights to the RIP and incoherency
constants, which ensures exact recovery. In a second part, we introduce a new
algorithm for matrix completion, based on the idea of iterative reweighting.
Since a weighted nuclear "norm" is typically non-convex, it cannot be used
easily as an objective function. So, we define a new estimator based on a
fixed-point equation. We give empirical evidences of the fact that this new
algorithm leads to strong improvements over nuclear norm minimization on
simulated and real matrix completion problems.
\\ ( http://arxiv.org/abs/1107.1638 ,  3557kb)
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\\
arXiv:1107.1639
Date: Fri, 8 Jul 2011 14:18:05 GMT   (6kb)

Title: Injectivity and flatness of semitopological modules
Authors: Henri Bourl\`es
Categories: math.OC math.AP math.CT
MSC-class: 18G50
\\
  The spaces D, S and E' over \mathbb{R}^(n) are known to be flat modules over
A=\mathbb{C}[\partial_{1},...,\partial_{n}], whereas their duals D', S' and E
are known to be injective modules over the same ring. Let A be a Noetherian
k-algebra (k=\mathbb{R} or \mathbb{C}). The above observation leads us to study
in this paper the link existing between the flatness of an A-module E which is
a locally convex topological k-vector space and the injectivity of its dual. We
show that, for dual pairs (E,E') which are (K) over A--a notion which is
explained in the paper--, injectivity of E' is a stronger condition than
flatness of E. A preprint of this paper (dated September 2009) has been quoted
and discussed in Shankar.
\\ ( http://arxiv.org/abs/1107.1639 ,  6kb)
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\\
arXiv:1107.1640
Date: Fri, 8 Jul 2011 14:20:33 GMT   (75kb)

Title: Nearest Neighbour Decoding with Pilot-Assisted Channel Estimation for
  Fading Multiple-Access Channels
Authors: A. Taufiq Asyhari and Tobias Koch and Albert Guill\'en i F\`abregas
Categories: cs.IT math.IT
Comments: 8 pages. Submitted to the Forty-Ninth Annual Allerton Conference on
  Communication, Control and Computing, Allerton Retreat Center, Monticello,
  IL, September 28-30, 2011
\\
  We study a noncoherent multiple-input multiple-output (MIMO) fading
multiple-access channel (MAC), where the transmitters and the receiver are
aware of the statistics of the fading, but not of its realisation. We analyse
the rate region that is achievable with nearest neighbour decoding and
pilot-assisted channel estimation and determine the corresponding pre-log
region, which is defined as the limiting ratio of the rate region to the
logarithm of the SNR as the SNR tends to infinity.
\\ ( http://arxiv.org/abs/1107.1640 ,  75kb)
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\\
arXiv:1107.1642
Date: Fri, 8 Jul 2011 14:24:03 GMT   (203kb)

Title: Indirect Channel Sensing for Cognitive Amplify-and-Forward Relay
  Networks
Authors: Yipeng Liu and Qun Wan
Categories: cs.IT math.IT
Comments: 5 pages, 5 figures
\\
  In cognitive radio network the primary channel information is beneficial. But
it can not be obtained by direct channel estimation in cognitive system as
pervious methods. And only one possible way is the primary receiver broadcasts
the primary channel information to the cognitive users, but it would require
the modification of the primary receiver and additional precious spectrum
resource. Cooperative communication is also a promising technique. And this
paper introduces an indirect channel sensing method for the primary channel in
cognitive amplify-and-forward (AF) relay network. As the signal retransmitted
from the primary AF relay node includes channel effects, the cognitive radio
can receive retransmitted signal from AF node, and then extract the channel
information from them. Afterwards, Least squares channel estimation and sparse
channel estimation can be used to address the dense and sparse multipath
channels respectively. Numerical experiment demonstrates that the proposed
indirect channel sensing method has an acceptable performance.
\\ ( http://arxiv.org/abs/1107.1642 ,  203kb)
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\\
arXiv:1107.1645
Date: Fri, 8 Jul 2011 14:32:26 GMT   (215kb,D)

Title: Knot state asymptotics I, AJ Conjecture and abelian representations
Authors: Laurent Charles and Julien Marche
Categories: math.GT math-ph math.MP math.SG
Comments: 47 pages, 2 figures
MSC-class: 57M27, 57R56, 53D50
\\
  Consider the Chern-Simons topological quantum field theory with gauge group
SU(2) and level k. Given a knot in the 3-sphere, this theory associates to the
knot exterior an element in a vector space. We call this vector the knot state
and study its asymptotic properties when the level is large. The latter vector
space being isomorphic to the geometric quantization of the SU(2)-character
variety of the peripheral torus, the knot state may be viewed as a section
defined over this character variety. We first conjecture that the knot state
concentrates in the large level limit to the character variety of the knot.
This statement may be viewed as a real and smooth version of the AJ conjecture.
Our second conjecture says that the knot state in the neighborhood of abelian
representations is a Lagrangian state. Using microlocal techniques, we prove
these conjectures for the figure eight and torus knots. The proof is based on
q-difference relations for the colored Jones polynomial. We also provide a new
proof for the asymptotics of the Witten-Reshetikhin-Turaev invariant of the
lens spaces and a derivation of the Melvin-Morton-Rozansky theorem from the two
conjectures.
\\ ( http://arxiv.org/abs/1107.1645 ,  215kb)
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\\
arXiv:1107.1646
Date: Fri, 8 Jul 2011 14:33:35 GMT   (79kb,D)

Title: Knot state asymptotics II, Witten conjecture and irreducible
  representations
Authors: Laurent Charles and Julien Marche
Categories: math.GT math-ph math.MP math.SG
Comments: 45 pages, 2 figures
MSC-class: 57M27, 57R56, 53D50
\\
  This article pursues the study of the knot state asymptotics in the large
level limit initiated in "Knot sate Asymptotics I". As a main result, we prove
the Witten asymptotic expansion conjecture for the Dehn fillings of the figure
eight knot. The state of a knot is defined in the realm of Chern-Simons
topological quantum field theory as a holomorphic section on the
SU(2)-character manifold of the peripheral torus. In the previous paper, we
conjectured that the knot state concentrates on the character variety of the
knot with a given asymptotic behavior on the neighborhood of the abelian
representations. In the present paper we study the neighborhood of irreducible
representations. We conjecture that the knot state is Lagrangian with a phase
and a symbol given respectively by the Chern-Simons and Reidemeister torsion
invariants. We show that under some mild assumptions, these conjectures imply
the Witten conjecture on the asymptotic expansion of WRT invariants of the Dehn
fillings of the knot. Using microlocal techniques, we show that the figure
eight knot state satisfies our conjecture starting from q-differential
relations verified by the colored Jones polynomials. The proof relies on a
differential equation satisfied by the Reidemeister torsion along the branches
of the character variety, a phenomenon which has not been observed previously
as far as we know.
\\ ( http://arxiv.org/abs/1107.1646 ,  79kb)
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\\
arXiv:1107.1650
Date: Fri, 8 Jul 2011 14:59:04 GMT   (9kb)

Title: On filling minimality of simple Finsler manifolds
Authors: Henrik Koehler
Categories: math.MG math.DG
Comments: 11 pages
MSC-class: 53C23, 53C60, 51K99
\\
  This paper states a formula for the difference of the Holmes-Thompson volumes
of two simple Finsler manifolds of arbitrary dimension, in terms of the
boundary distances and their derivatives. An application is a preconditioned
filling minimality result.
\\ ( http://arxiv.org/abs/1107.1650 ,  9kb)
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\\
arXiv:1107.1651
Date: Fri, 8 Jul 2011 15:05:16 GMT   (31kb)

Title: A regression Monte-Carlo method for Backward Doubly Stochastic
  Differential Equations
Authors: Omar Aboura (SAMM)
Categories: math.PR
\\
  This paper extends the idea of E.Gobet, J.P.Lemor and X.Warin from the
setting of Backward Stochastic Differential Equations to that of Backward
Doubly Stochastic Differential equations. We propose some numerical
approximation scheme of these equations introduced by E.Pardoux and S.Peng.
\\ ( http://arxiv.org/abs/1107.1651 ,  31kb)
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\\
arXiv:1107.1653
Date: Fri, 8 Jul 2011 15:07:45 GMT   (106kb,D)

Title: Multigrid methods for two-player zero-sum stochastic games
Authors: Marianne Akian and Sylvie Detournay
Categories: math.OC math.NA
Comments: 29 pages
MSC-class: 49L20, 65M55, 65K15, 49N70, 91A15, 91A05
\\
  We develop a fast numerical algorithm for large scale zero-sum stochastic
games with perfect information, which combines policy iteration and algebraic
multigrid methods. This algorithm can be applied either to a true finite state
space zero-sum two player game or to the discretization of an Isaacs equation.
We present numerical tests on discretizations of Isaacs equations or
variational inequalities. We also develop a full multi-level policy iteration,
similar to FMG, which allows one to improve substantially the computation time
for solving some variational inequalities.
\\ ( http://arxiv.org/abs/1107.1653 ,  106kb)
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\\
arXiv:1107.1654
Date: Fri, 8 Jul 2011 15:08:12 GMT   (364kb,D)

Title: Extrapolation of stable random fields
Authors: Wolfgang Karcher, Elena Shmileva, Evgeny Spodarev
Categories: math.PR
Comments: 19 pages, 8 figures, 2 tables
MSC-class: 60G60, 60G25, 62M20
\\
  In this paper, we discuss three extrapolation methods for alpha-stable random
fields with 1<alpha<=2. We justify them, giving proofs of the existence and
uniqueness of the solutions for each method and providing sufficient conditions
for path continuity. Two methods are based on minimizing the variability of the
difference between the predictor and the theoretical value, whereas in the
third approach we provide a new method that maximizes the covariation between
these two quantities.
\\ ( http://arxiv.org/abs/1107.1654 ,  364kb)
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\\
arXiv:1107.1657
Date: Thu, 7 Jul 2011 08:14:58 GMT   (19kb)

Title: Quantum isometry groups of symmetric groups
Authors: Jan Liszka-Dalecki, Piotr M. So{\l}tan
Categories: math.QA math.OA math.RA
Comments: LaTeX, 18 pages
MSC-class: 16T05, 58B34. 16T20
\\
  We identify the quantum isometry groups of spectral triples built on the
symmetric groups with length functions arising from the nearest-neighbor
transpositions as generators. It turns out that they are isomorphic to certain
"doubling" of the group algebras of the respective symmetric groups. We discuss
the doubling procedure in the context of regular multiplier Hopf algebras. In
the last section we study the dependence of the isometry group of S_n on the
choice of generators in the case n=3. We show that two different choices of
generators lead to non-isomorphic quantum isometry groups which exhaust the
list of non-commutative non-cocommutative semisimple Hopf algebras of dimension
12. This provides non-commutative geometric interpretation of these Hopf
algebras.
\\ ( http://arxiv.org/abs/1107.1657 ,  19kb)
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\\
arXiv:1107.1659
Date: Fri, 8 Jul 2011 15:36:40 GMT   (16kb,D)

Title: A Linear Programming Approach to Weak Reversibility and Linear Conjugacy
  of Chemical Reaction Networks
Authors: Matthew D. Johnston and David Siegel and G\'abor Szederk\'enyi
Categories: math.DS
Comments: 19 pages
MSC-class: 80A30, 90C35
\\
  A numerically effective procedure for determining weakly reversible chemical
reaction networks that are linearly conjugate to a known reaction network is
proposed in this paper. The method is based on translating the structural and
algebraic characteristics of weak reversibility to logical statements and
solving the obtained set of linear (in)equalities in the framework of mixed
integer linear programming. The unknowns in the problem are the reaction rate
coefficients and the parameters of the linear conjugacy transformation. The
efficacy of the approach is shown through numerical examples.
\\ ( http://arxiv.org/abs/1107.1659 ,  16kb)
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\\
arXiv:1107.1667
Date: Fri, 8 Jul 2011 16:05:42 GMT   (1574kb)

Title: Violating the Singular Cardinals Hypothesis Without Large Cardinals
Authors: Moti Gitik and Peter Koepke
Categories: math.LO
Comments: 18 pages, to appear in Israel Journal of Mathematics
MSC-class: 03E25, 03E35
\\
  We extend a transitive model V of ZFC + GCH cardinal preservingly to a model
N of ZF + "GCH holds below Alef_omega" + "there is a surjection from the power
set of Alef_omega onto lambda" where lambda is an arbitrarily high fixed
cardinal in V.
\\ ( http://arxiv.org/abs/1107.1667 ,  1574kb)
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\\
arXiv:1107.1669
Date: Fri, 8 Jul 2011 16:25:03 GMT   (19kb)

Title: A Relativistic Version of the Two-Level Atom in the Rest-Frame Instant
  Form of Dynamics
Authors: David Alba, Horace W. Crater, Luca Lusanna
Categories: math-ph hep-th math.MP
Comments: 23 pages
\\
  We define a relativistic version of the two-level atom, in which an extended
atom is replaced by a point particle carrying suitable Grassmann variables for
the description of the two-level structure and of the electric dipole. After
studying the isolated system "atom plus the electro-magnetic field" in the
electric-dipole representation as a parametrized Minkowski theory, we give its
restriction to the inertial rest frame and the explicit form of the Poincar\'e
generators. After quantization we get a two-level atom with a spin 1/2 electric
dipole and the relativistic generalization of the Hamiltonians of the Rabi and
Jaynes-Cummings models.
\\ ( http://arxiv.org/abs/1107.1669 ,  19kb)
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\\
arXiv:1107.1670
Date: Fri, 8 Jul 2011 16:26:34 GMT   (27kb)

Title: On p-Compact mappings and p-approximation
Authors: Silvia Lassalle and Pablo Turco
Categories: math.FA
Comments: 31 pages
MSC-class: 46G20, 46B28
\\
  The notion of $p$-compact sets arises naturally from Grothendieck's
characterization of compact sets as those contained in the convex hull of a
norm null sequence. The definition, due to Sinha and Karn (2002), leads to the
concepts of $p$-approximation property and $p$-compact operators, which form a
ideal with its ideal norm $\kappa_p$. This paper examines the interaction
between the $p$-approximation property and the space of holomorphic functions.
Here, the $p$-compact analytic functions play a crucial role. In order to
understand this type of functions we define a $p$-compact radius of convergence
which allow us to give a characterization of the functions in the class. We
show that $p$-compact holomorphic functions behave more like nuclear than
compact maps. We use the $\epsilon$-product, defined by Schwartz, to
characterize the $p$-approximation property of a Banach space in terms of
$p$-compact homogeneous polynomials and also in terms of $p$-compact
holomorphic functions with range on the space. Finally, we show that
$p$-compact holomorphic functions fit in the framework of holomorphy types
which allows us to inspect the $\kappa_p$-approximation property. Along these
notes we solve several questions posed by Aron, Maestre and Rueda.
\\ ( http://arxiv.org/abs/1107.1670 ,  27kb)
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\\
arXiv:1107.1675
Date: Fri, 8 Jul 2011 16:47:12 GMT   (17kb)

Title: Conformal pure radiation with parallel rays
Authors: Thomas Leistner and Pawel Nurowski
Categories: math.DG
Comments: 13 pages
MSC-class: 53A30, 53B30, 53C29
\\
  We define pure radiation metrics with parallel rays to be n-dimensional
pseudo-Riemannian metrics that admit a parallel null line bundle K and whose
Ricci tensor vanishes on vectors that are orthogonal to K. We give necessary
conditions in terms of the Weyl, Cotton and Bach tensors for a
pseudo-Riemannian metric to be conformal to a pure radiation metric with
parallel rays. Then we derive conditions in terms of tractor calculus that are
equivalent to the existence of a pure radiation metric with parallel rays in a
conformal class. We also give an analogous result for n-dimensional
pseudo-Riemannian pp-waves.
\\ ( http://arxiv.org/abs/1107.1675 ,  17kb)
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\\
arXiv:1107.1679
Date: Fri, 8 Jul 2011 17:26:41 GMT   (20kb)

Title: Umbilical submanifolds of $\mathbb{S}^n\times \mathbb{R}$
Authors: Bruno Mendon\c{c}a and Ruy Tojeiro
Categories: math.DG
Comments: 25 pages
\\
  We give a complete classification of umbilical submanifolds of arbitrary
dimension and codimension of $\mathbb{S}^n\times \mathbb{R}$, extending the
classification of umbilical surfaces in $\mathbb{S}^2\times \mathbb{R}$ by
Rabah-Souam and Toubiana as well as the local description of umbilical
hypersurfaces in $\mathbb{S}^n\times \mathbb{R}$ by Van der Vecken and
Vrancken. We prove that, besides small spheres in a slice, up to isometries of
the ambient space they come in a two-parameter family of rotational
submanifolds whose substantial codimension is either one or two and whose
profile is a curve in a totally geodesic $\Sf^1\times \mathbb{R}$ or
$\mathbb{S}^2\times \mathbb{R}$, respectively, the former case arising in a
one-parameter family. All of them are diffeomorphic to a sphere, except for a
single element that is diffeomorphic to Euclidean space. We obtain explicit
parametrizations of all such submanifolds. We also study more general classes
of submanifolds of $\mathbb{S}^n\times \mathbb{R}$ and $\mathbb{H}^n\times
\mathbb{R}$. In particular, we give a complete description of all submanifolds
in those product spaces that have flat normal bundle when regarded as
submanifolds of the underlying flat spaces. We prove a Dajczer-type reduction
of codimension theorem for submanifolds of $\mathbb{S}^n\times \mathbb{R}$ and
$\mathbb{H}^n\times \mathbb{R}$. As an application, we give a simple proof of a
recent result by Alencar, do Carmo and Tribuzzi on surfaces with parallel mean
curvature vector in $\mathbb{S}^n\times \mathbb{R}$ and $\mathbb{H}^n\times
\mathbb{R}$.
\\ ( http://arxiv.org/abs/1107.1679 ,  20kb)
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\\
arXiv:1107.1680
Date: Fri, 8 Jul 2011 17:31:12 GMT   (19kb)

Title: Developments in perfect simulation for Gibbs measures
Authors: Emilio De Santis, Andrea Lissandrelli
Categories: math.PR math-ph math.MP
Comments: 19 pages
MSC-class: 60K35, 82B20, 68U20, 60K35
\\
  This paper deals with the problem of perfect sampling from a Gibbs measure
with infinite range interactions. We present some sufficient conditions for the
extinction of processes which are like supermartingales when large values are
taken. This result has profound consequences on perfect simulation, showing
that local modifications on the interactions of a model do not affect the
simulability. We also pose the question to optimize over a sequence of sets and
we completely solve the question in the case of finite range interactions.
\\ ( http://arxiv.org/abs/1107.1680 ,  19kb)
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arXiv:1107.1685
Date: Fri, 8 Jul 2011 17:58:32 GMT   (12kb)

Title: A construction of 2-cofiltered bilimits of topoi
Authors: Eduardo J. Dubuc, Sergio Yuhjtman
Categories: math.CT
Comments: 7 pages
\\
  We show the existence of bilimits of 2-cofiltered diagrams of topoi,
generalizing the construction of cofiltered bilimits developed in "SGA 4
Springer LNM 270 (1972)". For any given such diagram, we show that it can be
represented by a 2-cofiltered diagram of small sites with finite limits, and we
construct a small site for the inverse limit topos. This is done by taking the
2-filtered bicolimit of the underlying categories and inverse image functors.
We use the construction of this bicolimit developed in "A construction of
2-filtered bicolimits of categories, Cah. Top. et Geo. Diff. Vol. XLVII-2
(2006)", where it is proved that if the categories in the diagram have finite
limits and the transition functors are exact, then the bicolimit category has
finite limits and the pseudocone functors are exact. An application of our
result here is the fact that every Galois topos has points "2-Filteredness and
the point of every Galois topos, Proc. CT2007, App. Cat. St., Vol. 18, 2,
(2010)".
\\ ( http://arxiv.org/abs/1107.1685 ,  12kb)
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arXiv:1107.1687
Date: Fri, 8 Jul 2011 18:02:29 GMT   (21kb)

Title: The Szeg\"o kernel for certain non-pseudoconvex domains in C^2
Authors: Michael Gilliam and Jennifer Halfpap
Categories: math.CV
Comments: 25 pages. To appear in the Illnois J. Math
MSC-class: 32T99, 42B20
\\
  We consider the Szeg\"o kernel for domains \Omega in C^2 given by \Omega =
{(z,w): Im w > b(Re z)} where b is a non-convex quartic polynomial with
positive leading coefficient. Such domains are not pseudoconvex. We describe
the subset of \bar{\Omega} \times \bar{\Omega} on which the kernel and all its
derivatives are finite. In particular, we show that there are points off the
diagonal of the boundary at which the Szeg\"o kernel is infitie as well as
points on the diagonal at which it is finite.
\\ ( http://arxiv.org/abs/1107.1687 ,  21kb)
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\\
arXiv:1107.1691
Date: Fri, 8 Jul 2011 18:19:31 GMT   (63kb)

Title: Minimum-Time Quantum Transport with Bounded Trap Velocity
Authors: Dionisis Stefanatos and Jr-Shin Li
Categories: math.OC quant-ph
MSC-class: 49K15, 93C05, 81V45
\\
  We formulate the problem of efficient transport of a quantum particle trapped
in a harmonic potential which can move with a bounded velocity, as a
minimum-time problem on a linear system with bounded input. We completely solve
the corresponding optimal control problem and obtain an interesting bang-bang
solution. These results are expected to find applications in quantum
information processing, where quantum transport between the storage and
processing units of a quantum computer is an essential step. They can also be
extended to the efficient transport of Bose-Einstein condensates, where the
ability to control them is crucial for their potential use as interferometric
sensors.
\\ ( http://arxiv.org/abs/1107.1691 ,  63kb)
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\\
arXiv:1107.1692
Date: Fri, 8 Jul 2011 18:19:44 GMT   (8kb)

Title: Under the Continuum Hypothesis all nonreflexive Banach space ultrapowers
  are primary
Authors: Piotr Wilzcek
Categories: math.LO math.FA
Comments: 7 pages
MSC-class: 46B08, 46B20, 46B25
\\
  In this note a large class of primary Banach spaces is characterized. Namely,
it will be demonstrated that under the Continuum Hypothesis the ultrapower of
any infinite dimensional nonsuperreflexive Banach space is always primary.
Consequently, any infinite dimensional nonsuperreflexive Banach space can be
isometrically embedded into its primary ultrapowers.
\\ ( http://arxiv.org/abs/1107.1692 ,  8kb)
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\\
arXiv:1107.1693
Date: Fri, 8 Jul 2011 18:25:43 GMT   (13kb)

Title: Some Representation Theorem for nonreflexive Banach space ultrapowers
  under the Continuum Hypothesis
Authors: Piotr Wilczek
Categories: math.LO math.FA
Comments: 12 pages
MSC-class: 46B08, 46B20, 46B25
\\
  In this paper it will be shown that assuming the Continuum Hypothesis (CH)
every nonreflexive Banach space ultrapower is isometrically isomorphic to the
space of continuous, bounded and real-valued functions on the Parovicenko
space. This Representation Theorem will be helpful in proving some facts from
geometry and topology of nonreflexive Banach space ultrapowers.
\\ ( http://arxiv.org/abs/1107.1693 ,  13kb)
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\\
arXiv:1107.1694
Date: Fri, 8 Jul 2011 18:31:39 GMT   (17kb)

Title: The Szeg\"o kernel for non-pseudoconvex tube domains in C^2
Authors: Michael Gilliam and Jennifer Halfpap
Categories: math.CV
Comments: 17 pages
MSC-class: 32T99, 42B20
\\
  We consider the Szeg\"o kernel for non-pseudoconvex domains in C^2 given by
\Omega = {(z,w): Im w > b(Re z)} for b a non-convex even-degree polynomial with
positive leading coefficient. This is an extension of results previously
obtained by the authors for the case in which b has degree 4. We show that the
Szeg\"o kernel has singularities off the diagonal of the boundary of
\bar{\Omega} \times \bar{\Omega} for all such domains, as well as points on the
diagonal of the boundary at which it is finite.
\\ ( http://arxiv.org/abs/1107.1694 ,  17kb)
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\\
arXiv:1107.1695
Date: Fri, 24 Jun 2011 02:34:47 GMT   (9kb)

Title: On Krawtchouk Transforms
Authors: Philip Feinsilver, Ren\'e Schott
Categories: cs.IT math.CA math.IT
Comments: 13 pages, presented at 10th International Conference on Artificial
  Intelligence and Symbolic Computation, AISC 2010, Paris, France, 5-6 July
  2010
MSC-class: Primary: 15.0, 15A69 Secondary: 05E35, 42C05
Journal-ref: Intelligent Computer Mathematics, 10th International Conference,
  AISC 2010, Paris, France, July 5-10, 2010. Proceedings. Springer 2010, pp.
  64-75
\\
  Krawtchouk polynomials appear in a variety of contexts, most notably as
orthogonal polynomials and in coding theory via the Krawtchouk transform. We
present an operator calculus formulation of the Krawtchouk transform that is
suitable for computer implementation. A positivity result for the Krawtchouk
transform is shown. Then our approach is compared with the use of the
Krawtchouk transform in coding theory where it appears in MacWilliams' and
Delsarte's theorems on weight enumerators. We conclude with a construction of
Krawtchouk polynomials in an arbitrary finite number of variables, orthogonal
with respect to the multinomial distribution.
\\ ( http://arxiv.org/abs/1107.1695 ,  9kb)
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\\
arXiv:1107.1698
Date: Fri, 8 Jul 2011 18:56:22 GMT   (31kb)

Title: Generic representations of abelian groups and extreme amenability
Authors: Julien Melleray (ICJ), Todor Tsankov (ELM)
Categories: math.LO math.DS
\\
  If $G$ is a Polish group and $\Gamma$ is a countable group, denote by
$\Hom(\Gamma, G)$ the space of all homomorphisms $\Gamma \to G$. We study
properties of the group $\cl{\pi(\Gamma)}$ for the generic $\pi \in
\Hom(\Gamma, G)$, when $\Gamma$ is abelian and $G$ is one of the following
three groups: the unitary group of an infinite-dimensional Hilbert space, the
automorphism group of a standard probability space, and the isometry group of
the Urysohn metric space. Under mild assumptions on $\Gamma$, we prove that in
the first case, there is (up to isomorphism of topological groups) a unique
generic $\cl{\pi(\Gamma)}$; in the other two, we show that the generic
$\cl{\pi(\Gamma)}$ is extremely amenable. We also show that if $\Gamma$ is
torsion-free, the centralizer of the generic $\pi$ is as small as possible,
extending a result of King from ergodic theory.
\\ ( http://arxiv.org/abs/1107.1698 ,  31kb)
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\\
arXiv:1107.1699
Date: Fri, 8 Jul 2011 18:57:11 GMT   (14kb)

Title: b-Stability and blow-ups
Authors: S.K.Donaldson
Categories: math.DG math.AG
MSC-class: 53C55
\\
  We extend an argument of Stoppa to make some prgress towards a proof that
K\"ahler-Einstein manifolds are "b-stable". We point out some algebro-geometric
questions, involving finite generation, that arise.
\\ ( http://arxiv.org/abs/1107.1699 ,  14kb)
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\\
arXiv:1107.1700
Date: Fri, 8 Jul 2011 19:04:59 GMT   (43kb)

Title: Wavelet analysis on adeles and pseudo-differential operators
Authors: A.Yu. Khrennikov (Vaxjo University), A.V. Kosyak (Institute of
  Mathematics, Kyiv), V.M. Shelkovich (St.-Petersburg State Architecture and
  Civil Engineering University)
Categories: math.FA
Comments: 45 pages
MSC-class: 11F85, 42C40, 47G30, 26A33, 46F10
\\
  This paper is devoted to wavelet analysis on adele ring $\bA$ and the theory
of pseudo-differential operators. We develop the technique which gives the
possibility to generalize finite-dimensional results of wavelet analysis to the
case of adeles $\bA$ by using infinite tensor products of Hilbert spaces. The
adele ring is roughly speaking a subring of the direct product of all possible
($p$-adic and Archimedean) completions $\bQ_p$ of the field of rational numbers
$\bQ$ with some conditions at infinity. Using our technique, we prove that
$L^2(\bA)=\otimes_{e,p\in\{\infty,2,3,5,...}}L^2({\bQ}_{p})$ is the infinite
tensor product of the spaces $L^2({\bQ}_{p})$ with a stabilization $e=(e_p)_p$,
where $e_p(x)=\Omega(|x|_p)\in L^2({\bQ}_{p})$, and $\Omega$ is a
characteristic function of the unit interval $[0,\,1]$, $\bQ_p$ is the field of
$p$-adic numbers, $p=2,3,5,...$; $\bQ_\infty=\bR$. This description allows us
to construct an infinite family of Haar wavelet bases on $L^2(\bA)$ which can
be obtained by shifts and multi-delations. The adelic multiresolution analysis
(MRA) in $L^2(\bA)$ is also constructed. In the framework of this MRA another
infinite family of Haar wavelet bases is constructed. We introduce the adelic
Lizorkin spaces of test functions and distributions and give the
characterization of these spaces in terms of wavelet functions. One class of
pseudo-differential operators (including the fractional operator) is studied on
the Lizorkin spaces. A criterion for an adelic wavelet function to be an
eigenfunction for a pseudo-differential operator is derived. We prove that any
wavelet function is an eigenfunction of the fractional operator. These results
allow one to create the necessary prerequisites for intensive using of adelic
wavelet bases and pseudo-differential operators in applications.
\\ ( http://arxiv.org/abs/1107.1700 ,  43kb)
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\\
arXiv:1107.1705
Date: Fri, 8 Jul 2011 19:22:18 GMT   (26kb)

Title: On natural derivatives and the curvature formula in fibre bundles
Authors: Giovanni Romano
Categories: math.DG
Comments: 13 pages
MSC-class: 53C05
\\
  In a fibre bundle, natural derivatives of a section are defined as tangent
vector fields on the image of a section of the fibre bundle. A local extension
to vector fields in the tangent bundle leads to a direct proof of the formula
expressing the curvature of a connection in terms of covariant derivatives. The
result is based on a tensoriality argument and extends to nonlinear connections
on fibre bundles a well-known formula for linear connections on vector bundles.
\\ ( http://arxiv.org/abs/1107.1705 ,  26kb)
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\\
arXiv:1107.1707
Date: Fri, 8 Jul 2011 19:35:32 GMT   (70kb)

Title: A polynomial bound on solutions of quadratic equations in free groups
Authors: Igor Lysenok, Alexei Myasnikov
Categories: math.GR
Comments: 41 pages, 10 figures
\\
  We provide polynomial upper bounds on the size of a shortest solution for
quadratic equations in a free group. A similar bound is given for parametric
solutions in the description of solutions sets of quadratic equations in a free
group.
\\ ( http://arxiv.org/abs/1107.1707 ,  70kb)
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\\
arXiv:1107.1709
Date: Fri, 8 Jul 2011 19:47:15 GMT   (228kb,D)

Title: Massive MIMO: How many antennas do we need?
Authors: Jakob Hoydis, Stephan ten Brink, Merouane Debbah
Categories: cs.IT math.IT
Comments: 10 pages, 3 figures
\\
  We consider a multicell MIMO uplink channel where each base station (BS) is
equipped with a large number of antennas N. Recent work has shown that, as N
grows infinitely large, (i) the simplest form of user detection, i.e., the
matched filter (MF), becomes optimal, (ii) the transmit power per user terminal
(UT) can be made arbitrarily small, (iii) the system performance is limited by
pilot contamination. The aim of this paper is to assess to which extent the
above conclusions hold true for large, but finite N. In particular, we derive
how many antennas per UT are needed to achieve \eta % of the ultimate
performance. We then study how much can be gained through more sophisticated
minimum-mean-square-error (MMSE) detection and how many more antennas are
needed with the MF to achieve the same performance. Our analysis relies on
novel results from random matrix theory which allow us to derive tight
approximations of the signal-to-interference-plus-noise-ratio (SINR) of a class
of linear receivers.
\\ ( http://arxiv.org/abs/1107.1709 ,  228kb)
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arXiv:1011.0397 (*cross-listing*)
Date: Mon, 1 Nov 2010 18:00:00 GMT   (132kb,D)
Date (revised v2): Fri, 8 Jul 2011 09:27:12 GMT   (110kb)

Title: Efficient Approximation of Optimal Control for Markov Games
Authors: John Fearnley, Markus Rabe, Sven Schewe, Lijun Zhang
Categories: cs.GT cs.SY math.OC
\\
  We study the time-bounded reachability problem for continuous-time Markov
decision processes (CTMDPs) and games (CTMGs). Existing techniques for this
problem use discretisation techniques to break time into discrete intervals,
and optimal control is approximated for each interval separately. Current
techniques provide an accuracy of O(\epsilon^2) on each interval, which leads
to an infeasibly large number of intervals. We propose a sequence of
approximations that achieve accuracies of O(\epsilon^3), O(\epsilon^4), and
O(\epsilon^5), that allow us to drastically reduce the number of intervals that
are considered. For CTMDPs, the performance of the resulting algorithms is
comparable to the heuristic approach given by Buckholz and Schulz, while also
being theoretically justified. All of our results generalise to CTMGs, where
our results yield the first practically implementable algorithms for this
problem. We also provide positional strategies for both players that achieve
similar error bounds.
\\ ( http://arxiv.org/abs/1011.0397 ,  110kb)
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\\
arXiv:1105.3612 (*cross-listing*)
Date: Wed, 18 May 2011 12:52:37 GMT   (13kb)
Date (revised v2): Fri, 8 Jul 2011 09:57:50 GMT   (14kb)

Title: Braided Tensor Products and the Covariance of Quantum Noncommutative
  Free Fields
Authors: Jerzy Lukierski and Mariusz Woronowicz (IFT, Wroclaw Univ.)
Categories: hep-th math-ph math.MP
Comments: 15 pages,v2. Mainly Sect 5 modified, new references added
\\
  We introduce the free quantum noncommutative fields as described by braided
tensor product. The multiplication of such fields is decomposed into three
operations, describing the multiplication in the algebra M of functions on
noncommutative space-time, the product in the algebra H of deformed field
oscillators, and the braiding by factor Psi_{M,H} between algebras M and H. For
noncommutativity generated by the twist factor we shall employ the star-product
realizations of the algebra M in terms of functions on standard Minkowski
space. The covariance of the noncommutative quantum fields under deformed
Poincare symmetries is described by the algebraic covariance conditions which
are equivalent to the deformation of generalized Heisenberg equations on
Poincare group manifold. We shall calculate the covariant braided field
commutator, which for free quantum noncommutative fields provides the field
quantization condition and is given by standard Pauli-Jordan function. For
ilustration of our scheme we present explicit calculations for the well-known
case in the literature of canonically deformed free quantum fields.
\\ ( http://arxiv.org/abs/1105.3612 ,  14kb)
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\\
arXiv:1107.1148 (*cross-listing*)
Date: Wed, 6 Jul 2011 14:56:23 GMT   (17kb)

Title: Discrete Integrable Systems and Hodograph Transformations Arising from
  Motions of Discrete Plane Curves
Authors: Bao-Feng Feng, Jun-ichi Inoguchi, Kenji Kajiwara, Ken-ichi Maruno and
  Yasuhiro Ohta
Categories: nlin.SI math-ph math.MP nlin.PS
Comments: 19 pages
MSC-class: 35Q51, 35C08, 37K10, 65Q10
\\
  We consider integrable discretizations of some soliton equations associated
with the motions of plane curves: the Wadati-Konno-Ichikawa elastic beam
equation, the complex Dym equation, and the short pulse equation. They are
related to the modified KdV or the sine-Gordon equations by the hodograph
transformations. Based on the observation that the hodograph transformations
are regarded as the Euler-Lagrange transformations of the curve motions, we
construct the discrete analogues of the hodograph transformations, which yield
integrable discretizations of those soliton equations.
\\ ( http://arxiv.org/abs/1107.1148 ,  17kb)
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\\
arXiv:1107.1511 (*cross-listing*)
Date: Thu, 7 Jul 2011 20:19:55 GMT   (1102kb)

Title: Cluster Synchrony in Systems of Coupled Phase Oscillators with
  Higher-Order Coupling
Authors: Per Sebastian Skardal, Edward Ott, Juan G. Restrepo
Categories: nlin.CD math.DS nlin.AO nlin.PS nlin.SI
Comments: 9 pages, 9 figures
\\
  We study the phenomenon of cluster synchrony that occurs in ensembles of
coupled phase oscillators when higher-order modes dominate the coupling between
oscillators. For the first time, we develop a complete analytic description of
the dynamics in the limit of a large number of oscillators and use it to
quantify the degree of cluster synchrony, cluster asymmetry, and switching. We
use a variation of the recent dimensionality-reduction technique of Ott and
Antonsen \cite{OA1} and find an analytic description of the degree of cluster
synchrony valid on a globally attracting manifold. Shaped by this manifold,
there is an infinite family of steady-state distributions of oscillators,
resulting in a high degree of multi-stability in the cluster asymmetry. We also
show how through external forcing the degree of asymmetry can be controlled,
and suggest that systems displaying cluster synchrony can be used to encode and
store data.
\\ ( http://arxiv.org/abs/1107.1511 ,  1102kb)
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arXiv:1107.1546 (*cross-listing*)
Date: Fri, 8 Jul 2011 02:16:01 GMT   (428kb)

Title: Decision Based Uncertainty Propagation Using Adaptive Gaussian Mixtures
Authors: Gabriel Terejanu, Puneet Singla, Tarunraj Singh, Peter D. Scott
Categories: stat.CO math.PR nlin.CD
Comments: The 12th International Conference on Information Fusion, Seattle,
  Washington, July 2009
\\
  Given a decision process based on the approximate probability density
function returned by a data assimilation algorithm, an interaction level
between the decision making level and the data assimilation level is designed
to incorporate the information held by the decision maker into the data
assimilation process. Here the information held by the decision maker is a loss
function at a decision time which maps the state space onto real numbers which
represent the threat associated with different possible outcomes or states. The
new probability density function obtained will address the region of interest,
the area in the state space with the highest threat, and will provide overall a
better approximation to the true conditional probability density function
within it. The approximation used for the probability density function is a
Gaussian mixture and a numerical example is presented to illustrate the
concept.
\\ ( http://arxiv.org/abs/1107.1546 ,  428kb)
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\\
arXiv:1107.1547 (*cross-listing*)
Date: Fri, 8 Jul 2011 02:20:59 GMT   (134kb)

Title: Approximate Interval Method for Epistemic Uncertainty Propagation using
  Polynomial Chaos and Evidence Theory
Authors: Gabriel Terejanu, Puneet Singla, Tarunraj Singh, Peter D. Scott
Categories: stat.CO math.PR stat.ME
Comments: 2010 American Control Conference, Baltimore, Maryland, June 2010
\\
  The paper builds upon a recent approach to find the approximate bounds of a
real function using Polynomial Chaos expansions. Given a function of random
variables with compact support probability distributions, the intuition is to
quantify the uncertainty in the response using Polynomial Chaos expansion and
discard all the information provided about the randomness of the output and
extract only the bounds of its compact support. To solve for the bounding range
of polynomials, we transform the Polynomial Chaos expansion in the Bernstein
form, and use the range enclosure property of Bernstein polynomials to find the
minimum and maximum value of the response. This procedure is used to propagate
Dempster-Shafer structures on closed intervals through nonlinear functions and
it is applied on an algebraic challenge problem.
\\ ( http://arxiv.org/abs/1107.1547 ,  134kb)
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arXiv:1107.1548 (*cross-listing*)
Date: Fri, 8 Jul 2011 02:25:20 GMT   (220kb)

Title: Approximate Propagation of both Epistemic and Aleatory Uncertainty
  through Dynamic Systems
Authors: Gabriel Terejanu, Puneet Singla, Tarunraj Singh, Peter D. Scott
Categories: stat.ME math.DS math.PR nlin.CD stat.CO
Comments: The 13th International Conference on Information Fusion, Edinburgh,
  UK, July 2010
\\
  When ignorance due to the lack of knowledge, modeled as epistemic uncertainty
using Dempster-Shafer structures on closed intervals, is present in the model
parameters, a new uncertainty propagation method is necessary to propagate both
aleatory and epistemic uncertainty. The new framework proposed here, combines
both epistemic and aleatory uncertainty into a second-order uncertainty
representation which is propagated through a dynamic system driven by white
noise. First, a finite parametrization is chosen to model the aleatory
uncertainty by choosing a representative approximation to the probability
density function conditioned on epistemic variables. The epistemic uncertainty
is then propagated through the moment evolution equations of the conditional
probability density function. This way we are able to model the ignorance when
the knowledge about the system is incomplete. The output of the system is a
Dempster-Shafer structure on sets of cumulative distributions which can be
combined using different rules of combination and eventually transformed into a
singleton cumulative distribution function using Smets' pignistic
transformation when decision making is needed.
\\ ( http://arxiv.org/abs/1107.1548 ,  220kb)
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\\
arXiv:1107.1549 (*cross-listing*)
Date: Fri, 8 Jul 2011 03:14:52 GMT   (296kb,D)

Title: The frequency-dependent Wright-Fisher model: diffusive and non-diffusive
  approximations
Authors: Fabio A. C. C. Chalub and Max O. Souza
Categories: q-bio.PE math.AP
MSC-class: 92D15, 92D25, 35K57, 35K67, 35L65
\\
  We study a class of processes that are akin to the Wright-Fisher model, with
transition probabilities weighted in terms of the frequency-dependent fitness
of the population types. Following an inverse numerical analysis approach, we
obtain a family of partial differential equations (PDE) for the evolution of
the probability density, and which will be an approximation of the discrete
process in the joint large population and weak selection limit. The equations
in this family can be purely diffusive, purely hyperbolic or of
convection-diffusion type, with frequency dependent convection, and the
particular outcome will depend on the assumed scalings. The diffusive equations
are of the degenerate type; using a duality approach, we also obtain a
frequency dependent version of the Kimura equation without any further
assumptions. We also show that the convective approximation is related to the
replicator dynamics and provide some estimate of how good is the convective
approximation. In particular, we show that the mode, but not the expected
value, of the probability distribution is modeled by the replicator dynamics.
Some numerical simulations that illustrate the results are also presented.
\\ ( http://arxiv.org/abs/1107.1549 ,  296kb)
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\\
arXiv:1107.1617 (*cross-listing*)
Date: Fri, 8 Jul 2011 12:02:05 GMT   (25kb)

Title: On optimal investment for a behavioural investor in multiperiod
  incomplete market models
Authors: Laurence Carassus and Miklos Rasonyi
Categories: q-fin.PM math.OC math.PR
MSC-class: 91G10
\\
  We provide easily verifiable conditions for the well-posedness of the optimal
investment problem for a behavioral investor in an incomplete discrete-time
multiperiod financial market model, for the first time in the literature. Under
suitable assumptions we also establish the existence of optimal strategies.
\\ ( http://arxiv.org/abs/1107.1617 ,  25kb)
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\\
arXiv:1107.1619 (*cross-listing*)
Date: Fri, 8 Jul 2011 12:39:22 GMT   (1221kb)

Title: Reconfigurable knots and links in chiral nematic colloids
Authors: Uro\v{s} Tkalec, Miha Ravnik, Simon \v{C}opar, Slobodan \v{Z}umer,
  Igor Mu\v{s}evi\v{c}
Categories: cond-mat.soft cond-mat.mtrl-sci math.GT
Comments: 6 pages, 3 figures
Journal-ref: Science 333, 62-65 (2011)
DOI: 10.1126/science.1205705
\\
  Tying knots and linking microscopic loops of polymers, macromolecules, or
defect lines in complex materials is a challenging task for material
scientists. We demonstrate the knotting of microscopic topological defect lines
in chiral nematic liquid crystal colloids into knots and links of arbitrary
complexity by using laser tweezers as a micromanipulation tool. All knots and
links with up to six crossings, including the Hopf link, the Star of David and
the Borromean rings are demonstrated, stabilizing colloidal particles into an
unusual soft matter. The knots in chiral nematic colloids are classified by the
quantized self-linking number, a direct measure of the geometric, or Berry's,
phase. Forming arbitrary microscopic knots and links in chiral nematic colloids
is a demonstration of how relevant the topology can be for the material
engineering of soft matter.
\\ ( http://arxiv.org/abs/1107.1619 ,  1221kb)
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arXiv:1107.1677 (*cross-listing*)
Date: Fri, 8 Jul 2011 16:57:45 GMT   (28kb)

Title: Series expansions from the corner transfer matrix renormalization group
  method: the hard squares model
Authors: Yao-ban Chan
Categories: cond-mat.stat-mech math.CO
Comments: 10 figures
MSC-class: 82B20
\\
  The corner transfer matrix renormalization group method is an efficient
method for evaluating physical quantities in statistical mechanical models. It
originates from Baxter's corner transfer matrix equations and method, and was
developed by Nishino and Okunishi in 1996. In this paper, we review and adapt
this method, previously used for numerical calculations, to derive series
expansions. We use this to calculate 92 terms of the partition function of the
hard squares model. We also examine the claim that the method is subexponential
in the number of generated terms and briefly analyse the resulting series.
\\ ( http://arxiv.org/abs/1107.1677 ,  28kb)
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arXiv:0809.0088
replaced with revised version Fri, 8 Jul 2011 14:24:24 GMT   (7kb)

Title: Generalized asymptotic Euler's relation for certain families of
  polytopes
Authors: Laszlo Major
Categories: math.CO
Comments: 6 pages; added section
MSC-class: 68R05
\\ ( http://arxiv.org/abs/0809.0088 ,  7kb)
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\\
arXiv:0907.2284
replaced with revised version Fri, 8 Jul 2011 08:21:13 GMT   (58kb)

Title: Orientability of linear Weingarten surfaces, spacelike CMC-1 surfaces
  and maximal surfaces
Authors: Masatoshi Kokubu and Masaaki Umehara
Categories: math.DG
Comments: 19 pages, 3 figures
\\ ( http://arxiv.org/abs/0907.2284 ,  58kb)
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arXiv:0908.0447
replaced with revised version Fri, 8 Jul 2011 19:36:45 GMT   (20kb)

Title: Wiener's 'closure of translates' problem and Piatetski-Shapiro's
  uniqueness phenomenon
Authors: Nir Lev and Alexander Olevskii
Categories: math.CA math.FA
MSC-class: 42A63 (Primary) 43A45, 47A16 (Secondary)
Journal-ref: Annals of Mathematics 174 (2011), 519-541
DOI: 10.4007/annals.2011.174.1.15
\\ ( http://arxiv.org/abs/0908.0447 ,  20kb)
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arXiv:0909.0799
replaced with revised version Fri, 8 Jul 2011 09:04:27 GMT   (29kb)

Title: The cusp amplitudes and quasi-level of a congruence subgroup of SL2 over
  any Dedekind domain
Authors: A. W. Mason, Andreas Schweizer
Categories: math.GR math.NT
Comments: 40 pages, refereed version, minor changes, second author's address
  updated
MSC-class: 11F06, 20G30, 20H05
\\ ( http://arxiv.org/abs/0909.0799 ,  29kb)
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arXiv:0911.3212
replaced with revised version Thu, 7 Jul 2011 20:50:58 GMT   (47kb)

Title: Transgression to Loop Spaces and its Inverse, I: Diffeological Bundles
  and Fusion Maps
Authors: Konrad Waldorf
Categories: math.DG
Comments: 45 pages, 1 figure; v2: parts of the appendix have been moved to the
  main text, many small improvements
\\ ( http://arxiv.org/abs/0911.3212 ,  47kb)
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arXiv:0911.4147
replaced with revised version Thu, 7 Jul 2011 21:14:48 GMT   (23kb)

Title: Smooth solutions to the abc equation: the xyz Conjecture
Authors: Jeffrey C. Lagarias and K. Soundararajan
Categories: math.NT
Comments: 21 pages, presented at 26th Journees Arithmetiques, 2009; v2 added
  new examples 1.2, updated references; v3 changed title, more examples added,
  notation changes, v4 corrects misprints in Conj. 3.1, Thm. 4.3 statement, 25
  pages
MSC-class: 11D61, 11P55
Journal-ref: J. Theor. Nombres Bordeaux 23 (2011), No. 1, 209--234
\\ ( http://arxiv.org/abs/0911.4147 ,  23kb)
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arXiv:0912.2255
replaced with revised version Fri, 8 Jul 2011 13:30:10 GMT   (38kb)

Title: Test ideals via algebras of $p^{-e}$-linear maps
Authors: Manuel Blickle
Categories: math.AC math.AG
Comments: 29 pages, to appear in Journal of Algebraic Geometry
MSC-class: 13A35, 14G17
\\ ( http://arxiv.org/abs/0912.2255 ,  38kb)
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arXiv:1008.2154
replaced with revised version Fri, 8 Jul 2011 00:56:52 GMT   (26kb)

Title: Nielsen equalizer theory
Authors: P. Christopher Staecker
Categories: math.GN math.AT math.GT
Comments: + addendum, sync with published version
Journal-ref: Topology and its Applications 158, 2011, p. 1615-1625
DOI: 10.1016/j.topol.2011.05.032
\\ ( http://arxiv.org/abs/1008.2154 ,  26kb)
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arXiv:1009.0143 (*cross-listing*)
replaced with revised version Fri, 8 Jul 2011 15:04:09 GMT   (416kb)

Title: A non-ergodic probabilistic cellular automaton with a unique invariant
  measure
Authors: Philippe Chassaing (IECN), Jean Mairesse (LIAFA)
Categories: cs.FL cs.DM math.PR
Comments: To appear in Stochastic Processes and their Applications
\\ ( http://arxiv.org/abs/1009.0143 ,  416kb)
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arXiv:1009.0498
replaced with revised version Fri, 8 Jul 2011 10:31:23 GMT   (5kb)

Title: One side invertibility for implicit hyperbolic systems with delays
Authors: Faouzi Haddouchi
Categories: math.OC cs.SY
Comments: Paper presented at the conference" The 3rd International IEEE
  Scientific Conference on Physics and Control (PhysCon 2007), September
  3rd-7th 2007 at the University of Potsdam, Germany
MSC-class: 93C15, 93C25
\\ ( http://arxiv.org/abs/1009.0498 ,  5kb)
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arXiv:1009.2892
replaced with revised version Fri, 8 Jul 2011 16:22:52 GMT   (22kb)

Title: A universality result for endomorphism monoids of some ultrahomogeneous
  structures
Authors: Igor Dolinka, Dragan Ma\v{s}ulovi\'c
Categories: math.GR math.LO
Comments: 20 pages; to appear in the Proceedings of the Edinburgh Mathematical
  Society
MSC-class: Primary 20M20, Secondary 03C15, 08A35, 18A30, 20M50
\\ ( http://arxiv.org/abs/1009.2892 ,  22kb)
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arXiv:1009.5847
replaced with revised version Fri, 8 Jul 2011 12:26:31 GMT   (49kb)

Title: Structure of Chinese algebras
Authors: Joanna Jaszunska, Jan Okninski
Categories: math.RA math.RT
MSC-class: 16S15 (Primary), 16S36, 16N60, 20M05, 20M25 (Secondary)
\\ ( http://arxiv.org/abs/1009.5847 ,  49kb)
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arXiv:1011.2474
replaced with revised version Fri, 8 Jul 2011 06:05:23 GMT   (18kb)

Title: Nontangential limits and Fatou-type theorems on post-critically finite
  self-similar sets
Authors: Ricardo A. S\'aenz
Categories: math.CA
Comments: 22 pages
MSC-class: 28A80, 31B25
\\ ( http://arxiv.org/abs/1011.2474 ,  18kb)
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arXiv:1011.3027
replaced with revised version Fri, 8 Jul 2011 13:57:21 GMT   (53kb)

Title: Introduction to the non-asymptotic analysis of random matrices
Authors: Roman Vershynin
Categories: math.PR cs.NA math.FA
Comments: 65 pages. A few typos corrected. This is a chapter for the book
  "Compressed Sensing: Theory and Applications" (eds. Y. Eldar and G.
  Kutyniok), Cambridge University Press, to appear
MSC-class: 60B20, 46B09
\\ ( http://arxiv.org/abs/1011.3027 ,  53kb)
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arXiv:1011.4735
replaced with revised version Fri, 8 Jul 2011 12:58:45 GMT   (73kb)

Title: Cech cocycles for differential characteristic classes -- An infinity-Lie
  theoretic construction
Authors: Domenico Fiorenza, Urs Schreiber, Jim Stasheff
Categories: math.AT hep-th math.DG
Comments: 90 pages. Added discussion of computations of homotopy fibers of the
  infinity-Chern-Weil homomorphism. As an application a section on higher
  twisted differential spin structures added; in particular twisted string
  structures and twisted fivebrane structures are briefly discussed. Expanded
  introduction. References added
\\ ( http://arxiv.org/abs/1011.4735 ,  73kb)
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arXiv:1011.6410
replaced with revised version Fri, 8 Jul 2011 13:31:02 GMT   (22kb)

Title: On Algebraically Integrable Differential Operators on an Elliptic Curve
Authors: Pavel Etingof and Eric Rains
Categories: math-ph math.CV math.MP
Journal-ref: SIGMA 7 (2011), 062
DOI: 10.3842/SIGMA.2011.062
\\ ( http://arxiv.org/abs/1011.6410 ,  22kb)
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arXiv:1011.6441
replaced with revised version Fri, 8 Jul 2011 09:50:06 GMT   (715kb,D)

Title: LP Decodable Permutation Codes based on Linearly Constrained Permutation
  Matrices
Authors: Tadashi Wadayama and Manabu Hagiwara
Categories: cs.IT math.CO math.IT math.RT
Comments: 29 pages, 7 figures, submitted to IEEE Transactions on Information
  Theory
\\ ( http://arxiv.org/abs/1011.6441 ,  715kb)
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arXiv:1012.2068
replaced with revised version Fri, 8 Jul 2011 03:44:21 GMT   (10kb)

Title: On maximal curves which are not Galois subcovers of the Hermitian curve
Authors: Iwan Duursma and Kit-Ho Mak
Categories: math.NT math.AG
Comments: 10 pages. Version 3 corrected an error in earlier versions
MSC-class: 11G20
\\ ( http://arxiv.org/abs/1012.2068 ,  10kb)
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arXiv:1012.4818
replaced with revised version Thu, 7 Jul 2011 21:08:41 GMT   (301kb,D)

Title: Outliers in the spectrum of iid matrices with bounded rank perturbations
Authors: Terence Tao
Categories: math.PR
Comments: 24 pages, 5 figures, to appear, Prob. Thy. and Related Fields. This
  is the final version, incorporating the referee comments
MSC-class: 60B20
\\ ( http://arxiv.org/abs/1012.4818 ,  301kb)
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arXiv:1012.5653 (*cross-listing*)
replaced with revised version Fri, 8 Jul 2011 17:47:46 GMT   (152kb)

Title: On the viscosity to entropy density ratio for unitary Bose and Fermi
  Gases
Authors: Andr\'e LeClair
Categories: cond-mat.quant-gas hep-th math-ph math.MP
Comments: 25 pages, 5 figures. v2: Minor addition on high T behavior; minor
  factors of 2 corrected, with no change in final result
\\ ( http://arxiv.org/abs/1012.5653 ,  152kb)
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arXiv:1101.2116
replaced with revised version Fri, 8 Jul 2011 19:59:27 GMT   (10kb)

Title: A Ganzstellensatz for open semi-algebraic sets in real closed valued
  fields
Authors: Noa Lavi
Categories: math.AG math.LO
\\ ( http://arxiv.org/abs/1101.2116 ,  10kb)
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arXiv:1101.2578
replaced with revised version Fri, 8 Jul 2011 19:08:35 GMT   (28kb)

Title: Inverse curvature flows in hyperbolic space
Authors: Claus Gerhardt
Categories: math.DG math.AP
Comments: 38 pages, v4: Dedication added; will appear in J. Diff. Geometry
\\ ( http://arxiv.org/abs/1101.2578 ,  28kb)
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arXiv:1102.4327
replaced with revised version Fri, 8 Jul 2011 16:18:14 GMT   (10kb)

Title: Characteristic Numbers and invariant subvarieties for Projective Webs
Authors: Maycol Falla Luza, Thiago Fassarella
Categories: math.AG math.CV
\\ ( http://arxiv.org/abs/1102.4327 ,  10kb)
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arXiv:1102.4911
replaced with revised version Thu, 7 Jul 2011 21:03:55 GMT   (33kb)

Title: Counting Smooth Solutions to the Equation A+B=C
Authors: J. C. Lagarias and K. Soundararajan
Categories: math.NT
Comments: 35 pages latex; v2 corrected misprints
MSC-class: 11D45 (primary), 11N25, 11P55 (secondary)
\\ ( http://arxiv.org/abs/1102.4911 ,  33kb)
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arXiv:1102.4916
replaced with revised version Fri, 8 Jul 2011 14:47:44 GMT   (13kb)

Title: Spencer Operator and Applications: From Continuum Mechanics to
  Mathematical Physics
Authors: Jean-Fran\c{c}ois Pommaret (CERMICS)
Categories: math.AP math-ph math.AC math.DG math.GR math.MP
Comments: Though a few of the results presented are proved in the recent
  references provided, the way they are combined with others and patched
  together around the three books quoted is new. In view of the importance of
  the full paper, the present version is only a summary of the definitive
  version to appear later on
\\ ( http://arxiv.org/abs/1102.4916 ,  13kb)
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arXiv:1102.5415 (*cross-listing*)
replaced with revised version Fri, 8 Jul 2011 16:56:44 GMT   (30kb)

Title: Privacy Amplification and Non-Malleable Extractors Via Character Sums
Authors: Xin Li and Trevor D. Wooley and David Zuckerman
Categories: cs.CR cs.CC math.NT
MSC-class: 94A62 (Primary) 11L40 (Secondary)
\\ ( http://arxiv.org/abs/1102.5415 ,  30kb)
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arXiv:1103.2059
replaced with revised version Fri, 8 Jul 2011 17:13:08 GMT   (22kb)

Title: The Walk Distances in Graphs
Authors: Pavel Chebotarev
Categories: math.CO cs.DM cs.SI math.MG
Comments: Version #4. A new conjecture added; presentation improved. 21 pages,
  2 figures
MSC-class: 05C12, 05C50, 15A48
\\ ( http://arxiv.org/abs/1103.2059 ,  22kb)
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arXiv:1103.2612 (*cross-listing*)
replaced with revised version Fri, 8 Jul 2011 09:03:00 GMT   (82kb,D)

Title: Control Synthesis for Constrained Nonlinear Systems using Hybridization
  and Robust Controllers on Simplices
Authors: Antoine Girard and Samuel Martin
Categories: cs.SY math.OC
\\ ( http://arxiv.org/abs/1103.2612 ,  82kb)
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arXiv:1103.3005
replaced with revised version Thu, 7 Jul 2011 22:06:11 GMT   (23kb)

Title: The Separation Principle in Stochastic Control, Redux
Authors: Tryphon T. Georgiou and Anders Lindquist
Categories: math.OC cs.SY
Comments: 18 pages, 7 figures revision: added references, revised Lemma 6
MSC-class: 93E20
\\ ( http://arxiv.org/abs/1103.3005 ,  23kb)
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arXiv:1104.2563
replaced with revised version Thu, 7 Jul 2011 20:55:52 GMT   (42kb)

Title: Section Extension from Hyperbolic Geometry of Punctured Disk and
  Holomorphic Family of Flat Bundles
Authors: Yum-Tong Siu
Categories: math.CV
MSC-class: 32L10, 14D20
\\ ( http://arxiv.org/abs/1104.2563 ,  42kb)
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arXiv:1104.3158
replaced with revised version Thu, 7 Jul 2011 20:22:54 GMT   (7kb)

Title: On the Maximum Number of Edges in a Hypergraph with a Unique Perfect
  Matching
Authors: Deepak Bal, Andrzej Dudek, Zelealem B. Yilma
Categories: math.CO
Comments: 5 pages
\\ ( http://arxiv.org/abs/1104.3158 ,  7kb)
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arXiv:1104.4345
replaced with revised version Fri, 8 Jul 2011 12:31:20 GMT   (38kb)

Title: Hitchhiker's guide to the fractional Sobolev spaces
Authors: Eleonora Di Nezza, Giampiero Palatucci and Enrico Valdinoci
Categories: math.FA math.AP
\\ ( http://arxiv.org/abs/1104.4345 ,  38kb)
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arXiv:1104.4607
replaced with revised version Fri, 8 Jul 2011 00:21:38 GMT   (26kb)

Title: Tree-Structured Random Vector Quantization for Limited-Feedback Wireless
  Channels
Authors: Wiroonsak Santipach and Kritsada Mamat
Categories: cs.IT math.IT
\\ ( http://arxiv.org/abs/1104.4607 ,  26kb)
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arXiv:1105.0876
replaced with revised version Fri, 8 Jul 2011 13:50:06 GMT   (12kb)

Title: Gaussian lower bound for the FIN diffusion
Authors: Manuel Cabezas
Categories: math.PR
\\ ( http://arxiv.org/abs/1105.0876 ,  12kb)
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arXiv:1105.2126
replaced with revised version Thu, 7 Jul 2011 20:49:20 GMT   (579kb,D)

Title: Fast First-Order Methods for Stable Principal Component Pursuit
Authors: Necdet Serhat Aybat, Donald Goldfarb and Garud Iyengar
Categories: math.OC
\\ ( http://arxiv.org/abs/1105.2126 ,  579kb)
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arXiv:1105.4401 (*cross-listing*)
replaced with revised version Fri, 8 Jul 2011 03:59:51 GMT   (11kb)

Title: Kohn's theorem and Galilean symmetry
Authors: P-M. Zhang and P.A. Horvathy
Categories: hep-th math-ph math.MP
Comments: 11 pages, no figures. To appear in Physics Letters B
\\ ( http://arxiv.org/abs/1105.4401 ,  11kb)
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arXiv:1105.5310
replaced with revised version Fri, 8 Jul 2011 09:13:42 GMT   (918kb)

Title: On emergence times in competition processes
Authors: Romain Bourget (LAREMA, PAVE), Lo\"ic Chaumont (LAREMA), Natalia
  Sapoukhina (PAVE)
Categories: math.PR
\\ ( http://arxiv.org/abs/1105.5310 ,  918kb)
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arXiv:1106.0936
replaced with revised version Fri, 8 Jul 2011 09:33:44 GMT   (8kb)

Title: Gunning-Narasimhan's theorem with a growth condition
Authors: Franc Forstneric and Takeo Ohsawa
Categories: math.CV
\\ ( http://arxiv.org/abs/1106.0936 ,  8kb)
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arXiv:1106.3878
replaced with revised version Fri, 8 Jul 2011 17:20:58 GMT   (9kb)

Title: Poisson Reduction
Authors: Chiara Esposito
Categories: math.DG
Comments: 13 pages
\\ ( http://arxiv.org/abs/1106.3878 ,  9kb)
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arXiv:1106.4348
replaced with revised version Fri, 8 Jul 2011 00:06:46 GMT   (421kb,D)

Title: The Integral of the Riemann xi-function
Authors: Jeffrey C. Lagarias and David Montague
Categories: math.NT math.CV
Comments: 23 pages, LaTeX
MSC-class: 11M26, (30D35)
\\ ( http://arxiv.org/abs/1106.4348 ,  421kb)
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arXiv:1107.0078
replaced with revised version Fri, 8 Jul 2011 05:12:09 GMT   (59kb)

Title: Optimization of UAV Heading for the Ground-to-Air Uplink
Authors: Feng Jiang and A. Lee Swindlehurst
Categories: cs.IT math.IT
Comments: 31 pages, 10 figures
\\ ( http://arxiv.org/abs/1107.0078 ,  59kb)
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arXiv:1107.1010
replaced with revised version Fri, 8 Jul 2011 15:21:35 GMT   (12kb)

Title: On the number of solutions to
  $\frac{4}{p}=\frac{1}{n_1}+\frac{1}{n_2}+\frac{1}{n_3}$
Authors: Terence Tao
Categories: math.NT
Comments: 15 pages, no figures. The paper is currently being revised in order
  to merge it with some closely related unpublished observations of Elsholtz
  and Heath-Brown. I am leaving this version up on the arXiv for now, but it
  will be superceded by a revised version in the future
MSC-class: 11D68
\\ ( http://arxiv.org/abs/1107.1010 ,  12kb)
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arXiv:1107.1131
replaced with revised version Fri, 8 Jul 2011 12:44:55 GMT   (783kb)

Title: Posets of Geometric Graphs
Authors: Debra L. Boutin, Sally Cockburn, Alice Dean and Andrei Margea
Categories: math.CO
Comments: 42 pages, 25 figures; co-author added in replaced version
MSC-class: 05C62
\\ ( http://arxiv.org/abs/1107.1131 ,  783kb)
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arXiv:1107.1301
replaced with revised version Fri, 8 Jul 2011 17:56:32 GMT   (21kb)

Title: A catalog of Cayley-Dickson-like products
Authors: John W. Bales
Categories: math.RA
\\ ( http://arxiv.org/abs/1107.1301 ,  21kb)
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arXiv:1107.1382
replaced with revised version Fri, 8 Jul 2011 03:44:40 GMT   (3310kb,D)

Title: Operations-Based Planning for Placement and Sizing of Energy Storage in
  a Grid With a High Penetration of Renewables
Authors: Krishnamurthy Dvijotham, Scott Backhaus and Misha Chertkov
Categories: math.OC cs.SY physics.soc-ph
\\ ( http://arxiv.org/abs/1107.1382 ,  3310kb)
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