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1002.0744v2 | Applications of the graphs to the Generalized Ornstein-Uhlenbeck process | We consider the generalized Ornstein- Uhlenbeck equation $\partial_t X=-m X_t+\eta$. In this paper We construct the Lévy noise $\eta$. The generalized Ornstein- Uhlenbeck process $X_t$ will be represented by a special types of graphs called rooted trees with two types of leaves. | Probability (math.PR) | This paper has been withdrawn by the author due to a crucial sign error in equation7 | factual/methodological/other critical errors in manuscript | 741 |
1002.1610v2 | Skew characters which contain only few components | Wrong assumptions were made in the proof of Theorem 3.12 and Lemma 3.6. A preprint containing a correct proof for Lemma 3.6 is in preparation and will be uploaded later this month. So the results of section 3 are correct, apart from Theorem 3.12 and the remarks following Theorem 3.12. | Combinatorics (math.CO) | Wrong assumptions were made in the proof of Theorem 3.12 and Lemma 3.6. A preprint containing a correct proof for Lemma 3.6 is in preparation and will be uploaded later this month. So the results of section 3 are correct, apart from Theorem 3.12 and the remarks following Theorem 3.12 | factual/methodological/other critical errors in manuscript | 748 |
1002.1941v5 | Construction of a renormalizable perturbative expansion for General Relativity | Every field theory, to have some hope of being renormalizable, has to be defined by a lagrangian which terms never exceed the mass dimensions [mass]^4. The dimension of a field is given by one half of four minus the number of derivatives in its kinetic term. This is strictly related to the mass dimensions of the coupling constant in the kinetic term. In particular, a theory has very few chances of being renormalizable if these dimensions are negative. This is what happens in General Relativity, where the coupling of the Hilbert-Einstein action has dimensions [m]^-2. We present here an equivalent formulation of the theory where the Hilbert-Einstein action doesn't contain kinetic terms, but only interaction terms. Moreover, a new kinetic term appears, which coupling has dimensions [m]^0. We suggest that maybe, in this formulation, General Relativity can be renormalized. | General Physics (physics.gen-ph) | This paper has been withdrawn by the author due to a crucial sign error in equation 1 | factual/methodological/other critical errors in manuscript | 750 |
1002.2004v3 | Generalized external cone condition for domains in manifolds | This note is dedicated to the study of the solvability of the Dirichlet problem in Riemannian manifolds. In particular, we discuss the p-regularity (regularity relative to the p-laplacian) of domains of the form I = O-K, where O is a regular domain and K is a regular submanifold of variable codimension giving a geometric and intuitive proof of this fact. We also prove a sort of generalized external cone condition for the regularity of domains in riemaniann manifolds. | Analysis of PDEs (math.AP) | This paper has been withdrawn by the author. Some of the results are not correct | factual/methodological/other critical errors in manuscript | 753 |
1002.2267v5 | On integrals of fractional parts and the theory of prime differences | In this paper we study the integrals of fractional parts of given functions, and develop some new tools to understand the behaviour of prime differences. We demonstrate how simply some seemingly difficult conjectures related to prime differences can be dealt with. Some, good results discussed here includes, the well know conjecture on prime gaps by Cramér and $\lim \inf_{n\to\infty} d_n < \infty$. Based on some simple assumptions, we have demonstrated how to tackle such problems. | General Mathematics (math.GM) | I have not been able to implement the intuition behind my ideas in a rigorous manner. Withdrawing due to errors in the paper | factual/methodological/other critical errors in manuscript | 756 |
1002.2395v4 | Newton's Inequalities on a Lattice | Functions that satisfy the Hadamard Fisher Inequalities also satisfy Newton's Inequalities | Combinatorics (math.CO) | This paper has been withdrawn due to an error in the statement of lemma 8. | factual/methodological/other critical errors in manuscript | 757 |
1002.2410v2 | Contextuality offers security | The discovery of quantum key distribution by Bennett and Brassard (BB84) bases on the fundamental quantum feature: incompatibility of measurements of quantum non-commuting observables. In 1991 Ekert showed that cryptographic key can be generated at a distance with help of entangled (correlated) quantum particles. Recently Barrett, Hardy and Kent showed that the non-locality used by Ekert is itself a good resource of cryptographic key even beyond quantum mechanics. Their result paved the way to new generation of quantum cryptographic protocols - secure even if the devices are built by the very eavesdropper. However, there is a question, which is fundamental from both practical and philosophical point of view: does Nature offer security on operational level based on the original concept behind quantum cryptography - that information gain about one bservables must cause disturbance to another, incompatible one? Here we resolve this problem by using in place of non-locality another striking feature of quantum world - contextuality. It is a strong version of incompatibility manifested in the famous Kochen-Specker paradox. The crucial concept is the use of a new class of families of bipartite probability distributions which locally exhibit the Kochen-Specker paradox conditions and, in addition, exhibit perfect correlations. We show that if two persons share systems described by such a family then they can extract secure key. This is the first operational protocol that directly implements the fundamental feature of Nature: the information gain vs. disturbance trade-off. At the same time it provides natural device-independent cryptographic scheme within quantum mechanics suitable for current technology. | Quantum Physics (quant-ph) | This paper has been withdrawn by the authors due to crucial error in the proof. A significantly revised version has appeared as arXiv:1006.0468 | factual/methodological/other critical errors in manuscript | 758 |
1002.2695v2 | An Unconditional large gap between the Zeros of the Riemann Zeta-Function and Existence of Conditional Large Gaps | In this paper, we prove the lower bound of the unconditional large gap is 3.5555 which improves the obtained value 3.079 in the literature. Next, on the hypothesis that the moments of the Hardy Z-function and its derivatives are correctly predicted we establish a new explicit formula of the gaps and use it to establish some lower bounds for k=3,4,...,15. In particular it is proved that lower bound when k=15 is 9.6435 which means that the consecutive nontrivial zeros often differ by at least 9.6435 times the average spacing. The main results are proved by employed an integral inequality with a best constant proved by David Boyd. | Number Theory (math.NT) | This paper has been withdrawn by the author. The inequality applied in this paper in not sharp | factual/methodological/other critical errors in manuscript | 761 |
1002.3071v2 | The effect of curvature and symmetry on stable stationary solutions in convex domains | We address the question of existence of nonconstant stable stationary solution to the heat equation on a class of convex domains subject to nonlinear boundary flux involving a positive parameter. Such solutions which were known to exist in dumbbell-type domains and not to exist in $N$-dimensional balls are shown to exist in some convex domains obtained by smoothing out, in a convenient way, the edges and corners of a cube. Therefore convexity of the domain is not a necessary condition for nonexistence of this type of solutions. If the parameter is small enough we prove that the only equilibria are the constant ones by using the Implicit Function Theorem in a special setting. Symmetry inheritance by local minimizers from symmetry properties of the domain is also addressed. | Analysis of PDEs (math.AP) | This paper has been withdrawn by the author due to a scaling error which invalidate the ilustration provided for the convex domain.. | factual/methodological/other critical errors in manuscript | 762 |
1002.3148v2 | A Model for the Pr1-xCaxMnO3 Series with x = 0.30-0.50 under Application of Weak Magnetic Fields | We introduce a proposal for explaining manganites behavior, in the Pr1-xCaxMnO3 series with x=0.30-0.50. We carry out computer simulations for the Oguchi model along with the crystal field contribution. We contrast the outcomings to experimental measurements made with a commercial magnetometer SQUID. For analyzing the magnetization drop at low temperatures, we take into account quasi-probability distributions. | Strongly Correlated Electrons (cond-mat.str-el) | The unit system that has been utilized is wrong | factual/methodological/other critical errors in manuscript | 764 |
1002.4219v5 | Does a measurement really collapse the wave function? | A single-particle multi-branched wave-function is studied. Usual which-path tests show that if the detector placed on one branch clicks, the detectors on the other branches remain silent. By the collapse postulate, after this click, the state of the particle is reduced to a single branch, the branch on which the detector clicked. The present article challenges the collapse postulate, claiming that when one branch of the wave-function produces a click in a detector, the other branches don't disappear. They can't produce clicks in detectors, but they are still there. An experiment different from which-path test is proposed, which shows that detectors are responsible for strongly decohering the wave-function, but not for making parts of it disappear. Moreover, one of the branches supposed to disappear may produce an interference pattern with a wave-packet of another particle. | Quantum Physics (quant-ph) | This article is outdated. New researches show that the collapse hypothesis is correct. See the article "[REDACTED-NAME] and in Criticism of the Model of [REDACTED-NAME] Localization of the Wave-Function" to appear in JQIS vol. 10, no. 4, December 2020 | factual/methodological/other critical errors in manuscript | 772 |
1002.4365v2 | The $K$-theory spectrum of the reduced group $C^\ast$-algebra is a functor | We construct $C^\ast$-categories that are anologues of the categories used in controlled algebraic $K$-theory. We then show that the reduced $C^\ast$-algebra of a finitely presented group and an associated controlled $C^\ast$-category have equivalent $K$-theory spectra, and that, at least in certain special cases, the associated $C^\ast$-category depends functorially on the group. Thus in these cases the $K$-theory spectrum of the reduced group $C^\ast$-algebra is a functor. | K-Theory and Homology (math.KT) | The paper has been withdrawn due to a crucial error. A restricted version of the result stated is still true, and will appear in due course. | factual/methodological/other critical errors in manuscript | 776 |
1002.4851v2 | Entire solutions of the Donaldson equation and complex Monge-Ampere equation | In this short note we shall construct infinite many nontrivial entire solutions to Donaldson equation and complex Monge-Ampere equation; in particular these examples give infinite many Kahler Ricci-flat but non-flat complete metrics on complex Euclidean spaces. We shall also prove a Liouville type theorem for entire solutions of the Donaldson equation; we believe that one should be able to classify all entire solutions of the Donaldson equation. | Analysis of PDEs (math.AP) | This paper is withdrawn by the author due to a blunder on the examples in Theorem 2.2 | factual/methodological/other critical errors in manuscript | 781 |
1003.0092v2 | Vortex-Antivortex Pair Unbinding Driven by the Spin Texture of a Ferromagnet-Superconductor Bilayer | We report the observation of a pronounced dip in the in-plane field (H//) dependence of the critical current density Jc(H) and a peak in resistance R(H) of a NbN-HoNi5 bilayer at temperatures below the magnetic ordering temperature (TCurie ~ 5.5 K) of HoNi5, which is lower than the onset temperature (~ 9 K) of superconductivity in the NbN layer. The extrema in Jc(H) and R(H) appear at fields much below the upper critical field of NbN. It is suggested that the origin of this feature is linked with the non-collinear magnetization of HoNi5 whose normal component assists in depairing of Pearl vortex-antivortex pairs in the system. A spin reorientation transition driven by the H// diminishes this normal component and consequently the excess dissipation. | Superconductivity (cond-mat.supr-con) | This paper has been withdrawn by the author due to a crucial sign error in analysis | factual/methodological/other critical errors in manuscript | 787 |
1003.0212v2 | An Exact Solution to the Yukawa System in Four Dimensions | An exact, closed form solution to the scalar Yukawa system in four dimensions is presented. The formalism is used to state and prove a theorem on the initial value problem. The method also works for a general, iso-vector form of the interacting system. We close with some comments on the quantum version of this problem. | Mathematical Physics (math-ph) | This paper has been withdrawn by the author due to a conceptual error in the domain of definition of the proposed solution | factual/methodological/other critical errors in manuscript | 790 |
1003.0380v2 | A 2-dimensional Complex Kleinian Group With Infinite Lines in the Limit Set Lying in General Position | In this article we present an example of a discrete group $\Sigma_\C\subset PSL(3,\Bbb{R})$ whose action on $¶^2$ does no have invariant projective subspaces, is not conjugated to complex hyperbolic group and its limit set in the sense of Kulkarni on $\Bbb{P}^2_\Bbb{C}$ has infinite lines in general position. | Dynamical Systems (math.DS) | This paper has been withdrawn by the author due to a crucial sign error | factual/methodological/other critical errors in manuscript | 794 |
1003.0737v2 | Knots in homology spheres which have simple knot Floer homology are trivial | We show that if K is a non-trivial knot inside a homology sphere X, the rank of the knot Floer homology group associated with K is strictly bigger than the rank of the Heegaard Floer homology group associated with X. | Geometric Topology (math.GT) | This paper has been withdrawn by the author. The surgery formulas are used incorrectly for obtaining the main result of the paper | factual/methodological/other critical errors in manuscript | 798 |
1003.1884v4 | An optimal order error estimate for the variational discretization of optimal control problems in the presence of pointwise control and state constraints | We consider the variational discretization of a linear-quadratic optimal control problem with pointwise control and state constraints. In order to allow for a Fréchet smooth norm, the problem is reformulated by means of a reflexive Sobolev space instead of the space of continuous functions. The discretization of the state equation yields a family of perturbed optimal control problems, whose solutions can be computed numerically. We apply an implicit multifunction theorem (IMT) to the first order necessary conditions to proof a bound on the perturbation error for these solutions. In order to verify the abstract regularity condition of the IMT, we compute the Fréchet coderivative of a set-valued representation of the necessary conditions. Applying our results to an elliptic state equation in two dimensions, undergoing a simple finite element discretization, we obtain convergence of order O(h). | Optimization and Control (math.OC) | Withdrawn due to an error in the proof of Lemma 3.3 | factual/methodological/other critical errors in manuscript | 807 |
1003.2042v2 | Mannheim Partner D-Curves in Euclidean 3-space | In this paper we consider the idea of Mannheim partner curves for curves lying on surfaces and by considering the Darboux frames of them we define these curves as Mannheim partner D-curves and give the characterizations for these curves. We also find the relations between the geodesic curvatures, the normal curvatures and the geodesic torsions of these associated curves. Furthermore, we show that the definition and the characterizations of Mannheim partner D-curves include those of Mannheim partner curves in some special cases. | Differential Geometry (math.DG) | 10 pages There are some mistakes in the proof of theorems. | factual/methodological/other critical errors in manuscript | 808 |
1003.2043v2 | Mannheim Partner D-Curves in Minkowski 3-space | In this paper, we give the definition, different types and characterizations of Mannheim partner D-curves in Minkowski 3-space. We find the relations between the geodesic curvatures, the normal curvatures and the geodesic torsions of these associated curves. Furthermore, we show that the definition and the characterizations of Mannheim partner D-curves include those of Mannheim partner curves in some special cases in Minkowski 3-space. | Differential Geometry (math.DG) | 15 pages There are some mistakes in the proof of theorems. | factual/methodological/other critical errors in manuscript | 809 |
1003.2044v2 | Bertrand Partner D-Curves in Euclidean 3-space | In this paper we consider the idea of Bertrand curves for curves lying on surfaces and by considering the Darboux frames of them we define these curves as Bertrand D-curves and give the characterizations for these curves. We also find the relations between the geodesic curvatures, the normal curvatures and the geodesic torsions of these associated curves. Furthermore, we show that the definition and the characterizations of Bertrand D-curves include those of Bertrand curves in some special cases. | Differential Geometry (math.DG) | 10 pages There are some mistakes in the proof of theorems. | factual/methodological/other critical errors in manuscript | 810 |
1003.2048v2 | Bertrand Partner D-Curves in Minkowski 3-space | In this paper, we consider the idea of Bertrand curves for curves lying on surfaces in Minkowski 3-space. By considering the Darboux frame, we define these curves as Bertrand D-curves and give the characterizations for those curves. We also find the relations between the geodesic curvatures, the normal curvatures and the geodesic torsions of these associated curves. Furthermore, we show that in Minkowski 3-space, the definition and the characterizations of Bertrand D-curves include those of Bertrand curves in some special cases. | Differential Geometry (math.DG) | 14 pages There are some mistakes in the proof of theorems. | factual/methodological/other critical errors in manuscript | 811 |
1003.2056v3 | From the Hamiltonian formalism to Spin-Foams | Starting from a BF-type formulation of General Relativity in the canonical formalism, we construct a physical scalar product with no restrictions for the boundary states that, for particular cases, reproduce the E.P.R. amplitude. | General Relativity and Quantum Cosmology (gr-qc) | This paper has been withdrawn by the author due to a crucial sign error in equation 1 | factual/methodological/other critical errors in manuscript | 812 |
1003.2200v5 | Lefschetz Fibrations on Compact Stein Manifolds | Here we prove that up to diffeomorphism every compact Stein manifold W of dimension 2n+2>4 admits a Lefschetz fibration over the two-disk with Stein regular fibers, such that the monodromy of the fibration is a symplectomorphism induced by compositions of right-handed Dehn twists along embedded Lagrangian n-spheres on the generic fiber. This generalizes the Stein surface case of n=1, previously proven by Loi-Piergallini and Akbulut-Ozbagci. More precisely, we show that up to Liouville isomorphism any Weinstein domain W admits a compatible compact convex Lefschetz fibration with Weinstein regular fibers and with the same monodromy description stated above. Moreover, the induced convex open book supports the induced contact structure on the boundary of W. | Geometric Topology (math.GT) | 33 pages, 11 figures (There is an error in resolving the double points of Lagrangian spheres.) | factual/methodological/other critical errors in manuscript | 814 |
1003.2705v2 | Generators of Picard modular groups | In this paper, we extend the method in [FFLP] to obtain the generators of the Picard modular groups $\mathbf{PU}(2,1;\mathcal {O}_d)$ with $d=3,7,11$. | Group Theory (math.GR) | This paper has been withdrawn by the author due to big errors in the cases when d=7,11 | factual/methodological/other critical errors in manuscript | 818 |
1003.2816v4 | Finite Rank Bratteli Diagrams and their Invariant Measures | In this paper we study ergodic measures on non-simple Bratteli diagrams of finite rank that are invariant with respect to the cofinal equivalence relation. We describe the structure of finite rank diagrams and prove that every ergodic invariant measure (finite or infinite) is an extension of a finite ergodic measure defined on a simple subdiagram. We find some algebraic criteria in terms of entries of incidence matrices and their norms under which such an extension remains a finite measure. Furthermore, the support of every ergodic measure is explicitly determined. We also give an algebraic condition for a diagram to be uniquely ergodic. It is proved that Vershik maps (not necessarily continuous) on finite rank Bratteli diagrams cannot be strongly mixing and always have zero entropy with respect to any finite ergodic invariant measure. A number of examples illustrating the established results is included. | Dynamical Systems (math.DS) | The paper has been withdrawn due to critical errors in Section 4, which also affected the proofs of Section 5 | factual/methodological/other critical errors in manuscript | 821 |
1003.3703v3 | Does Zeeman's Fine Topology Exist? | We work on the family of topologies for the Minkowski manifold M. We partially order this family by inclusion to form the lattice \Sigma(M), and focus on the sublattice Z of topologies that induce the Euclidean metric space on every time axis and every space axis. We analyze the bounds of Z in the lattice \Sigma(M), in search for its supremum. Our conclusion --that such a supremum does not belong in Z-- is compared with constructive proofs of existence of the fine topology, defined as the maximum of Z and conceived to play an essential role in contemporary physical theories. Essential mathematical and physical questions arise. | Mathematical Physics (math-ph) | This paper has been withdrawn by the author due to a substancial error in equation 25, which does not hold true | factual/methodological/other critical errors in manuscript | 829 |
1003.4910v2 | On the representations of $N(T)$ via prime numbers | In this paper, under the RH, we give a new representation of $N(T)$ in term of sum of the logarithms of the powers of prime numbers and compute the difference between the new representation and Guinand representation. | General Mathematics (math.GM) | This paper has been withdrawn by the author due to a crucial error in the last page. | factual/methodological/other critical errors in manuscript | 845 |
1003.4948v3 | Generic points on exponential curves | We show, assuming Schanuel's conjecture, that every irreducible complex polynomial in two variables where both variables appear has infinitely many algebraically independent solutions of the form (z,e^z). | Number Theory (math.NT) | We withdraw the article due to a mistake in the proof of the main theorem. | factual/methodological/other critical errors in manuscript | 846 |
1003.5507v2 | Prüfer- like conditions in the amalgamated duplication of a ring along an ideal | In this paper, we consider five possible extensions of the Prüfer domain notion to the case of commutative rings with zero-divisors. We investigate the transfer of these Prüfer-like properties between a ring $R$ and $R\bowtie I$; his amalgamated duplication along some ideal $I$, and then generate new and original families of rings with these properties. | Commutative Algebra (math.AC) | This paper has been withdrawn by the author due to a gap in the proof of the main result | factual/methodological/other critical errors in manuscript | 854 |
1003.5739v4 | The Strengthened Hanna Neumann Conjecture I: A Combinatorial Proof | We prove the Strengthened Hanna Neumann Conjecture, in its common graph theoretic formulation. Our original approach to this conjecture used cohomology of sheaves on graphs, although here we give a short combinatorial proof that we found in a succession of simplifications of the cohomological approach. Our proof is inductive, and requires Tardos' previous result settling the rank two case of the conjecture. | Combinatorics (math.CO) | This has been withdrawn due to an error | factual/methodological/other critical errors in manuscript | 856 |
1003.6020v2 | More accurate approximations for the Gamma function | A series transformation idea inspired by a formula of R. W. Gosper and some asymptotic expansions for the central binomial coefficients leads us to new accurate approximations for the Gamma function. | Classical Analysis and ODEs (math.CA) | 12 pages. This paper has been withdrawn by the author due to an error in page 5 line 21 | factual/methodological/other critical errors in manuscript | 862 |
1004.0134v2 | Globally coupled chaotic maps with bistable behaviour: Large deviations | For a system of globally coupled chaotic maps with bistable behaviour we relate the rate function for large deviations in the system size at finite time to dynamical properties of the self consistent Perron-Frobenius operator (SCPFO) that describes the system in the infinite size limit. | Dynamical Systems (math.DS) | This paper has been withdrawn by the author due to a severe error in the proof of the main result and some (less severe) errors in section 2. A much less general version of the main theorem remains true, though | factual/methodological/other critical errors in manuscript | 864 |
1004.0354v2 | Rotational symmetry of 3D gradient steady Ricci solitons | This paper has been withdrawn by the author due to an error | Differential Geometry (math.DG) | This paper has been withdrawn by the author due to an error | factual/methodological/other critical errors in manuscript | 866 |
1004.0378v7 | Facial Expression Representation and Recognition Using 2DHLDA, Gabor Wavelets, and Ensemble Learning | In this paper, a novel method for representation and recognition of the facial expressions in two-dimensional image sequences is presented. We apply a variation of two-dimensional heteroscedastic linear discriminant analysis (2DHLDA) algorithm, as an efficient dimensionality reduction technique, to Gabor representation of the input sequence. 2DHLDA is an extension of the two-dimensional linear discriminant analysis (2DLDA) approach and it removes the equal within-class covariance. By applying 2DHLDA in two directions, we eliminate the correlations between both image columns and image rows. Then, we perform a one-dimensional LDA on the new features. This combined method can alleviate the small sample size problem and instability encountered by HLDA. Also, employing both geometric and appearance features and using an ensemble learning scheme based on data fusion, we create a classifier which can efficiently classify the facial expressions. The proposed method is robust to illumination changes and it can properly represent temporal information as well as subtle changes in facial muscles. We provide experiments on Cohn-Kanade database that show the superiority of the proposed method. KEYWORDS: two-dimensional heteroscedastic linear discriminant analysis (2DHLDA), subspace learning, facial expression analysis, Gabor wavelets, ensemble learning. | Computer Vision and Pattern Recognition (cs.CV) | This paper has been withdrawn by the author due to an error in experimental results | factual/methodological/other critical errors in manuscript | 867 |
1004.1040v2 | Dimer Smectic in Extended Quantum Dimer Model -approach from pseudo S=1 Hamiltonian- | We extend Quantum Dimer Model (QDM) introduced by Rokhsar and Kivelson in such a way that the model includes resonance processes on larger loops. The strategy is to ?first construct a pseudo spin Hamiltonian which is defi?ned not by the S =1/2 but by the S=1 representation and then establish the correspondence between the pseudo-spin-1 con?figurations and those of dimers. The standard QDM keeps only the lowest resonance processes for pairs of parallel dimers and its validity in describing the realistic spin systems is not obvious. Our extended QDM (EQDM) improves this point and contains a novel resonance term, which is equivalent to two successive actions of the familiar parallel dimer resonance. For a certain choice of the coupling constants, our model exhibits three exotic valence-bond phases (herringbone, checkerboard and 'dimer smectic') in the ground state, which meet at a triple point. The checkerboard phase has four-fold rotational symmetry, while the dimer smectic is characterized by partial ordering only in one of the two directions. In the dimer smectic phase, we investigate the dimer-dimer correlation by using an analogy to random walks. | Strongly Correlated Electrons (cond-mat.str-el) | 16pages, 28 figures. This paper has been withdrawn due to a crucial sign error in FIG.14 | factual/methodological/other critical errors in manuscript | 873 |
1004.1237v2 | Lightweight Distance bound Protocol for Low Cost RFID Tags | Almost all existing RFID authentication schemes (tag/reader) are vulnerable to relay attacks, because of their inability to estimate the distance to the tag. These attacks are very serious since it can be mounted without the notice of neither the reader nor the tag and cannot be prevented by cryptographic protocols that operate at the application layer. Distance bounding protocols represent a promising way to thwart relay attacks, by measuring the round trip time of short authenticated messages. All the existing distance bounding protocols use random number generator and hash functions at the tag side which make them inapplicable at low cost RFID tags. This paper proposes a lightweight distance bound protocol for low cost RFID tags. The proposed protocol based on modified version of Gossamer mutual authentication protocol. The implementation of the proposed protocol meets the limited abilities of low-cost RFID tags. | Cryptography and Security (cs.CR) | Results in paper questionable. Article withdrawn by authors. | factual/methodological/other critical errors in manuscript | 876 |
1004.1399v2 | A note on the entropy of repetitive sequences of symmetry group permutations | The paper makes the observation that all orders of information entropy are equal in signals composed of repeating units of distinct symbols where the units can be classified as a member of a symmetry group. This leads to an improved metric for measuring the information content of higher order entropies in data such as text, signals, or genetics and another measure of similarity to compare the incremental information content across entropy orders when comparing data of different sizes and symbol sets or when comparing entire sequences. | Information Theory (cs.IT) | Paper has been witdrawn pending corrections to equations and formalism; 3 pages, no figures | factual/methodological/other critical errors in manuscript | 877 |
1004.1569v2 | A Streaming Approximation Algorithm for Klee's Measure Problem | The efficient estimation of frequency moments of a data stream in one-pass using limited space and time per item is one of the most fundamental problem in data stream processing. An especially important estimation is to find the number of distinct elements in a data stream, which is generally referred to as the zeroth frequency moment and denoted by $F_0$. In this paper, we consider streams of rectangles defined over a discrete space and the task is to compute the total number of distinct points covered by the rectangles. This is known as the Klee's measure problem in 2 dimensions. We present and analyze a randomized streaming approximation algorithm which gives an $(\epsilon, \delta)$-approximation of $F_0$ for the total area of Klee's measure problem in 2 dimensions. Our algorithm achieves the following complexity bounds: (a) the amortized processing time per rectangle is $O(\frac{1}{\epsilon^4}\log^3 n\log\frac{1}{\delta})$; (b) the space complexity is $O(\frac{1}{\epsilon^2}\log n \log\frac{1}{\delta})$ bits; and (c) the time to answer a query for $F_0$ is $O(\log\frac{1}{\delta})$, respectively. To our knowledge, this is the first streaming approximation for the Klee's measure problem that achieves sub-polynomial bounds. | Data Structures and Algorithms (cs.DS) | This paper has been withdrawn by the author due to a small technical error in Algorithm 3 and 4 | factual/methodological/other critical errors in manuscript | 879 |
1004.1749v3 | Capacity Achieving Low Density Parity Check Lattices | The concept and existence of sphere-bound-achieving and capacity-achieving lattices has been explained on AWGN channels by Forney. LDPC lattices, introduced by Sadeghi, perform very well under iterative decoding algorithm. In this work, we focus on an ensemble of regular LDPC lattices. We produce and investigate an ensemble of LDPC lattices with known properties. It is shown that these lattices are sphere-bound-achieving and capacity-achieving. As byproducts we find the minimum distance, coding gain, kissing number and an upper bound for probability of error for this special ensemble of regular LDPC lattices. | Information Theory (cs.IT) | This paper has been withdrawn by the author due to an error in an equation | factual/methodological/other critical errors in manuscript | 881 |
1004.1814v5 | Existential Second Order Logic Expression With Horn First Order for Maximum Clique (Decision Version) | We show that the maximum clique problem (decision version) can be expressed in existential second order (ESO) logic, where the first order part is a Horn formula in second-order quantified predicates. Without ordering, the first order part is $\Pi_2$ Horn; if ordering is used, then it is universal Horn (in which case, the second order variables can be determined in polynomial time). UPDATE: Manuscript withdrawn, because results are incorrect. If phi = phi_1 AND phi_2, and phi is a Horn formula, it does NOT mean that both phi_1 and phi_2 are Horn formulae. Furthermore, the cardinality constraint CANNOT be expressed as a universal Horn sentence in ESO (NOT even when the structure is ordered). Graedel's theorem is valid at a lower (machine) level, but probably NOT at a higher level. | Computational Complexity (cs.CC) | Manuscript withdrawn, because results are incorrect. If phi = phi_1 AND phi_2, and phi is a Horn formula, it does NOT mean that both phi_1 and phi_2 are Horn formulae. Furthermore, the cardinality constraint CANNOT be expressed as a universal Horn sentence in ESO (NOT even when the structure is ordered). Graedel's theorem is valid at a lower (machine) level, but probably NOT at a higher level | factual/methodological/other critical errors in manuscript | 882 |
1004.1871v3 | Asymptotically Secure Quantum Oblivious Transfer | Due to the commonly known impossibility results, unconditional security for oblivious transfer is seen as impossible even in the quantum world. In this paper, we try to overcome these impossibility results by proposing a protocol which is asymptotically secure. The protocol makes use of the basic properties of non-orthogonal quantum states. Apart from security, the advantages of our protocol include the fact that the honest players do not need to have quantum memory or create entanglement between individual qubits. The relation of our work to the known impossibility results is also discussed. | Quantum Physics (quant-ph) | This paper has been withdrawn by the authors because the scheme may be insecure, due to an attack provided by Crépeau Claude. | factual/methodological/other critical errors in manuscript | 883 |
1004.2236v2 | Anisotropic Structure of the Order Parameter in FeSe_{0.4}Te_{0.6} Revealed by Angle Resolved Specific Heat | The symmetry and structure of the superconducting gap in the Fe-based superconductor are the central issue for understanding these novel materials. So far the experimental data and theoretical models have been highly controversial. Some experiments favor two or more constant or nearly-constant gaps, others indicate strong anisotropy and yet others suggest gap zeros ("nodes"). Theoretical models also vary, suggesting that the absence or presence of the nodes depends quantitatively on the model parameters. An opinion that has gained substantial currency is that the gap structure, unlike all other known superconductors, including cuprates, may be different in different compounds within the same family. A unique method for addressing this issue, one of the very few methods that are bulk and angle-resolved, calls for measuring the electronic specific heat in a rotating magnetic field, as a function of field orientation with respect to the crystallographic axes. In this Communication we present the first such measurement for an Fe-based high-Tc superconductor (FeBSC). We observed a fourfold oscillation of the specific heat as a function of the in-plane magnetic field direction, which allowed us to identify the locations of the gap minima (or nodes) on the Fermi surface. Our results place severe restrictions on the gap structure and on the existing theoretical models. | Superconductivity (cond-mat.supr-con) | This paper is replaced by a new one appearing on 22 July 2010. A mistake in determining the angle of the positions of minima/maxima of C/T with respect to the crystallographic axes in the original paper will be corrected, together with the new and repeatable data obtained from a new sample with much improved quality. The new paper arXiv:this http URL supersedes this paper arXiv:1004.2236 | factual/methodological/other critical errors in manuscript | 891 |
1004.2421v4 | Torques in atmospheres of rotating planets | Molecular motion in combination with rotation causes a torque in gas when seen from a coordinate system fixed in the rotating system. The torque is caused by Coriolis forces. | Earth and Planetary Astrophysics (astro-ph.EP) | 5 pages, 1 figure, withdrawn due to high approximations and wrong force type | factual/methodological/other critical errors in manuscript | 892 |
1004.2424v2 | Large diffusion expansion of the transition kernel of the Lévy Ornstein-Uhlenbeck process | In this paper we study the Lévy Ornstein- Uhlenbeck equation $\partial_t X_t=-m\,X_t+\eta$. The transition kernel of the Lévy Ornstein- Uhlenbeck process is given by a series which is not convergent in general, a large diffusion expansion of the transition kernel of the Lévy Ornstein- Uhlenbeck process will be given as well. The obtained series can be re-expressed in terms of generalized Feynman graphs and Feynman rules. | Mathematical Physics (math-ph) | 12 pages, This paper has been withdrawn by the author due to a crucial sign error in page5 | factual/methodological/other critical errors in manuscript | 895 |
1004.3327v2 | An Efficient Hybrid Data Gathering Scheme in Wireless Sensor Networks | This paper has been withdrawn by the author due to a crucial sign error in equation 1 | Networking and Internet Architecture (cs.NI) | This paper has been withdrawn by the author due to a crucial sign error in equation 1 | factual/methodological/other critical errors in manuscript | 904 |
1004.3407v2 | An Optimized Lifetime Enhancement Scheme for Data Gathering in Wireless Sensor Networks | This paper has been withdrawn by the author due to a crucial sign error in equation 1 | Networking and Internet Architecture (cs.NI) | This paper has been withdrawn by the author due to a crucial sign error in equation 1 | factual/methodological/other critical errors in manuscript | 906 |
1004.3408v2 | An Energy Efficient Scheme for Data Gathering in Wireless Sensor Networks Using Particle Swarm Optimization | This paper has been withdrawn by the author due to a crucial sign error in equation 1 | Networking and Internet Architecture (cs.NI) | This paper has been withdrawn by the author due to a crucial sign error in equation 1 | factual/methodological/other critical errors in manuscript | 907 |
1004.3646v2 | Quantization of Schrodinger-Virasoro Lie algebra | Using the general quantization method by Drinfel'd twists to quantize the SchrÄodinger- Virasoro algebra with its Lie bialgebra structure determined by Han-Su, and by constructing two different kinds of Drinfel'd twists, we obtain two new Hopf this http URL result extends the class of examples of noncommutative and noncocommutative Hopf algebras. | Quantum Algebra (math.QA) | This paper has been withdrawn by the author due to a crucial sign error in equation 1 | factual/methodological/other critical errors in manuscript | 909 |
1004.3930v2 | A proof of Halperin-Carlsson Conjecture for free Z_2-torus actions on manifolds | This paper has been withdrawn due to a gap in the proof of the main result. | Algebraic Topology (math.AT) | This paper has been withdrawn due to a gap in the proof of the main result. | factual/methodological/other critical errors in manuscript | 910 |
1004.4154v2 | Simulation of Wireless Sensor Networks Using TinyOS- A case Study | This paper has been withdrawn by the author due to a crucial sign error in equation 1 | Networking and Internet Architecture (cs.NI) | This paper has been withdrawn by the author due to a crucial sign error in equation 1 | factual/methodological/other critical errors in manuscript | 913 |
1004.4309v2 | An integral breakdown criterion for Einstein vacuum equations in the case of asymptotically flat spacetimes | We will give in this paper the proof of an integral breakdown criterion for Einstein vacuum equations. In a recent article of this http URL and this http URL a new breakdown criterion was proved as a result of a sequence of articles involving new techniques. However, in this article, the authors mentioned that it was likely possible to prove a sharper result involving an integral condition instead of a pointwise one. This paper is concerned with giving the proof of this improvement. Moreover the proof of this breakdown criterion was written in the original article for a foliation of constant mean curvature, we will present it here for a maximal foliation which leads to some difficulties due to the non-compacity of the leaves of such a foliation and the use of weighted Sobolev norms. | Mathematical Physics (math-ph) | This paper has been withdrawn by the author. paper removed for mistakes in part 2, corrected version to come | factual/methodological/other critical errors in manuscript | 916 |
1004.4333v2 | The Pimsner-Voiculescu sequence of the Drinfeld-Jimbo algebra | We study the triangulated $KK$-category equivariant with respect to Woronowitz deformations of a compact Lie group and their duals; the Drinfeld-Jimbo twists of the universal enveloping Lie algebra. The Pimsner-Voiculescu sequence is generalized to a Pimsner-Voiculescu tower describing the $KK$-category equivariant with respect to Drinfeld-Jimbo twists of the dual of a compact Lie group satisfying the Hodgkin condition. A dual Pimsner-Voiculescu tower is used to show that the Drinfeld-Jimbo twists of a simply connected, compact Lie group satisfy the Baum-Connes property. The dual Pimsner-Voiculescu tower is also used to show that the $KK$-category equivariant with respect to $SU_q(2)$ is, up to triangulated equivalence, independent of $q$. | K-Theory and Homology (math.KT) | The paper has been withdrawn by the author due to a fatal error in a crucial lemma. | factual/methodological/other critical errors in manuscript | 917 |
1004.5594v2 | Bilinear control of discrete spectrum Schrödinger operators | The bilinear control problem of the Schrödinger equation $i\frac{\partial}{\partial t}\psi(t)$ $=(A+u(t) B)\psi(t)$, where $u(t)$ is the control function, is investigated through topological irreducibility of the set $\mathfrak{M}=\{e^{-it (A+u B)}, u\in \mathbb{R}, t>0\}$ of bounded operators. This allows to prove the approximate controllability of such systems when the uncontrolled Hamiltonian $A$ has a simple discrete spectrum and under an appropriate assumption on $B$. | Mathematical Physics (math-ph) | This paper has been withdrawn by the authors due to a crucial gap in the proof of the main theorem. | factual/methodological/other critical errors in manuscript | 931 |
1005.0010v2 | Limit Theorems for Competitive Density Dependent Population Processes | Near the beginning of the century, Wright and Fisher devised an elegant, mathematically tractable model of gene reproduction and replacement that laid the foundation for contemporary population genetics. The Wright-Fisher model and its extensions have given biologists powerful tools of statistical inference that enabled the quantification of genetic drift and selection. Given the utility of these tools, we often forget that their model - for mathematical, and not biological reasons - makes assumptions that are violated in most real-world populations. In this paper, I consider an alternative framework that merges P. A. P. Moran's continuous-time Markov chain model of allele frequency with the density dependent models of ecological competition proposed by Gause, Lotka and Volterra, that, unlike Moran's model allow for a stochastically varying -- but bounded -- population size. I require that allele numbers vary according to a density-dependent population process, for which the limiting law of large numbers is a dissipative, irreducible, competitive dynamical system. Under the assumption that this limiting system admits a codimension one submanifold of attractive fixed points -- a condition that naturally generalises the weak selection regime of classical population dynamics -- it is shown that for an appropriate rescaling of time, the finite dimensional distributions of the original process converge to those of a diffusion process on the submanifold. Weak convergence results are also obtained for a related process. | Probability (math.PR) | This paper has been withdrawn by the author. The proofs herein contain errors. I do not intend to prepare a revised version | factual/methodological/other critical errors in manuscript | 932 |
1005.0261v2 | A Remark on Coclosed G_2-Structures | We prove that Einstein coclosed G_2-structures are nearly parallel. | Differential Geometry (math.DG) | This paper has been withdrawn due to an error in equation 18 | factual/methodological/other critical errors in manuscript | 934 |
1005.0427v2 | The tame level 1 eigencurve is proper | This paper has been withdrawn. | Number Theory (math.NT) | This paper has been withdrawn by the author due to a serious flaw pointed out by [REDACTED-NAME] and [REDACTED-NAME] | factual/methodological/other critical errors in manuscript | 937 |
1005.1120v2 | Estimating small moments of data stream in nearly optimal space-time | For each $p \in (0,2]$, we present a randomized algorithm that returns an $\epsilon$-approximation of the $p$th frequency moment of a data stream $F_p = \sum_{i = 1}^n \abs{f_i}^p$. The algorithm requires space $O(\epsilon^{-2} \log (mM)(\log n))$ and processes each stream update using time $O((\log n) (\log \epsilon^{-1}))$. It is nearly optimal in terms of space (lower bound $O(\epsilon^{-2} \log (mM))$ as well as time and is the first algorithm with these properties. The technique separates heavy hitters from the remaining items in the stream using an appropriate threshold and estimates the contribution of the heavy hitters and the light elements to $F_p$ separately. A key component is the design of an unbiased estimator for $\abs{f_i}^p$ whose data structure has low update time and low variance. | Data Structures and Algorithms (cs.DS) | Withdrawn due to error in analysis | factual/methodological/other critical errors in manuscript | 940 |
1005.1122v2 | Estimating small frequency moments of data stream: a characteristic function approach | A data stream is viewed as a sequence of $M$ updates of the form $(\text{index},i,v)$ to an $n$-dimensional integer frequency vector $f$, where the update changes $f_i$ to $f_i + v$, and $v$ is an integer and assumed to be in $\{-m, ..., m\}$. The $p$th frequency moment $F_p$ is defined as $\sum_{i=1}^n \abs{f_i}^p$. We consider the problem of estimating $F_p$ to within a multiplicative approximation factor of $1\pm \epsilon$, for $p \in [0,2]$.
Several estimators have been proposed for this problem, including Indyk's median estimator \cite{indy:focs00}, Li's geometric means estimator \cite{pinglib:2006}, an \Hss-based estimator \cite{gc:random07}. The first two estimators require space $\tilde{O}(\epsilon^{-2})$, where the $\tilde{O}$ notation hides polylogarithmic factors in $\epsilon^{-1}, m, n$ and $M$. Recently, Kane, Nelson and Woodruff in \cite{knw:soda10} present a space-optimal and novel estimator, called the log-cosine estimator.
In this paper, we present an elementary analysis of the log-cosine estimator in a stand-alone setting. The analysis in \cite{knw:soda10} is more complicated. | Data Structures and Algorithms (cs.DS) | Withdrawn due to an error in proof of Lemma 2.2 (acknowledgement: [REDACTED-NAME], [REDACTED-NAME]) | factual/methodological/other critical errors in manuscript | 941 |
1005.1238v2 | Finite generation of lattices on products of trees | We prove that an irreducible lattice acting on a product of two or more
locally finite, biregular trees is finitely generated. | Group Theory (math.GR) | This paper has been withdrawn by the authors due to an error in Lemma 5 | factual/methodological/other critical errors in manuscript | 943 |
1005.1462v2 | $R^+$ is regular in characteristic $p$ | $R^+$ is regular in characteristic $p$ | Commutative Algebra (math.AC) | This paper has been withdrawn due to a gap in the proof of the main result | factual/methodological/other critical errors in manuscript | 945 |
1005.2150v2 | Isometries and curvatures of tangent sphere bundles | Natural metric structures on tangent bundles and tangent sphere bundles enclose many important problems, from the topology of the base to the determination of their holonomy. We make here a brief study of the topic. We find the characteristic classes of some of those structures. We solve the question of when two given tangent sphere bundles S_rM of a Riemannian manifold M,g are homothetic, assuming different variable radius functions r and weighted metrics induced only by the conformal class of g. We determine their Riemannian, Ricci, scalar and mean curvatures in some cases. We find a family of positive scalar curvature metrics on S_rM when M has positive scalar curvature or when it has bounded sectional curvature and index of nullity 0. Our objective is the study of contact structures and gwistor spaces, a recently found natural G_2-structure on S_1M. | Differential Geometry (math.DG) | This paper has been withdrawn by the author due to an error in equation 90. The final conclusions are therefore not true | factual/methodological/other critical errors in manuscript | 953 |
1005.2254v9 | On Universal Complexity Measures | We relate the computational complexity of finite strings to universal representations of their underlying symmetries. First, Boolean functions are classified using the universal covering topologies of the circuits which enumerate them. A binary string is classified as a fixed point of its automorphism group; the irreducible representation of this group is the string's universal covering group. Such a measure may be used to test the quasi-randomness of binary sequences with regard to first-order set membership. Next, strings over general alphabets are considered. The complexity of a general string is given by a universal representation which recursively factors the codeword number associated with a string. This is the complexity of the representation recursively decoding a Godel number having the value of the string; the result is a tree of prime numbers which forms a universal representation of the string's group symmetries. | Information Theory (cs.IT) | The paper has been withdrawn due to the poor predictive performance of circuit complexity vs. universal data compression. Given this fact, as well as the high computational complexity, the method seems to have little practical utility | factual/methodological/other critical errors in manuscript | 955 |
1005.2764v2 | The equivariant K-theory of the affine Grassmannian of SU(2) | Let $G=SU(2)$ and $\Omega G$ the space of based loops in SU(2). Motivated by the theory of Hamiltonian $LG$-spaces, we explicitly compute the topological equivariant $K$-theory $K_G^*(\Omega G)$ as an $R(G)$-module. | Algebraic Topology (math.AT) | This paper has been withdrawn due to some errors | factual/methodological/other critical errors in manuscript | 959 |
1005.2823v2 | External Description for Multivariable Systems Sampled in an Aperiodic Way | An external description for nonperiodically sampled multivariable linear systems has been developed. Emphasis is on the sampling period sequence, included among the variables to be handled. The computational procedure is simple and no use of polynomial matrix theory is required. This input/output description is believed to be a basic formulation for its later application to the problem of optimal control and/or identification of linear dynamical systems. | Dynamical Systems (math.DS) | There are several errors that need to be corrected. This is the reason why I prefer to withdraw the paper | factual/methodological/other critical errors in manuscript | 960 |
1005.3698v3 | An improvement on the upper bound of exponential sums connected to holomorphic cusp forms | We improve the known upper bound for short exponential sums and increase the range on which a sharp upper bound is known. | Number Theory (math.NT) | This article is withdrawn due to a crucial error in the reasonings | factual/methodological/other critical errors in manuscript | 969 |
1005.3807v9 | A model of the twisted $K$-theory related to bundles of finite order | In the present paper we propose a geometric model of the twisted K-theory corresponding to elements of finite order in $H^3(X, \mathbb{Z})\times [X, \BBSU_\otimes]$. | K-Theory and Homology (math.KT) | This paper has been withdrawn by the author due to a crucial error | factual/methodological/other critical errors in manuscript | 970 |
1005.4089v8 | A background-free lattice gauge theory of quantum gravity | The search for a quantum theory of gravity has become one of the most well-known problems in theoretical physics. Problems quantizing general relativity because it is not renormalizable have led to a search for a new theory of gravity that, while still agreeing with measured observations, is renormalizable. In this paper, I show that, given a "vortex" model of elementary particles in which rest mass derives from intrinsic spin and polarization, a Yang-Mills force with a SO(4,1) group symmetry predicts post-Newtonian N-body motion such as solar system observations of gravitational behavior as well as binary pulsar precession and orbital speed-up caused by gravitational radiation-reaction. Yang-Mills theory of the SO(4,1) group is defined on a lattice graph such that a background manifold is not required-a property unique to the (anti-) de Sitter and Poincaré groups. It predicts the accelerating expansion of the universe as a consequence of the de Sitter group Lie algebra-an acceleration that I show does not occur in the Poincaré group approximation-suggesting that the de Sitter group symmetry explains dark energy. In addition, with quantized mass, because it is a generic massless, semi-simple Yang-Mills theory, it is mathematically proved to be a perturbatively renormalizable quantum theory. | Mathematical Physics (math-ph) | This paper has been withdrawn because of a critical error in how the stress-energy tensors are derived | factual/methodological/other critical errors in manuscript | 972 |
1005.4360v2 | Questions of controllability and observability for nonuniformly sampled discrete systems | A joint characterisation of the controllability and observability of a particular kind of discrete system has been developed. The key idea of the procedure can be reduced to a correct choice of the sampling sequence. This freedom, owing to the arbitrary choice of the sampling instants, is used to improve the sensitivity of system controllability and observability, by exploiting an adequate geometric structure. Some qualitative examples are presented for illustrative purposes. | Dynamical Systems (math.DS) | There are several equations that must be corrected | factual/methodological/other critical errors in manuscript | 976 |
1005.5082v3 | A Note on Sparse Minimum Variance Portfolios and Coordinate-Wise Descent Algorithms | In this short report, we discuss how coordinate-wise descent algorithms can be used to solve minimum variance portfolio (MVP) problems in which the portfolio weights are constrained by $l_{q}$ norms, where $1\leq q \leq 2$. A portfolio which weights are regularised by such norms is called a sparse portfolio (Brodie et al.), since these constraints facilitate sparsity (zero components) of the weight vector. We first consider a case when the portfolio weights are regularised by a weighted $l_{1}$ and squared $l_{2}$ norm. Then two benchmark data sets (Fama and French 48 industries and 100 size and BM ratio portfolios) are used to examine performances of the sparse portfolios. When the sample size is not relatively large to the number of assets, sparse portfolios tend to have lower out-of-sample portfolio variances, turnover rates, active assets, short-sale positions, but higher Sharpe ratios than the unregularised MVP. We then show some possible extensions; particularly we derive an efficient algorithm for solving an MVP problem in which assets are allowed to be chosen grouply. | Portfolio Management (q-fin.PM) | This paper has been withdrawn by the author due to a crucial sign error in equation 1 | factual/methodological/other critical errors in manuscript | 982 |
1005.5580v2 | Magnetism in graphite oxide: The role of epoxy groups | We investigate the magnetism in graphite by controlled oxidation. Our approach renders graphite an insulator while maintaining its structure. Fourier transform infrared spectroscopy and X-ray absorption near edge structure spectra reveal that graphite oxide has epoxy groups on its surface and it is not thermally stable. Magnetic susceptibility data exhibit negative Curie temperature, field irreversibility, and slow relaxation. The magnetic properties diminish after the epoxy groups are destroyed. The overall results indicate the unexpected magnetism is associated with the presence of epoxy groups. | Strongly Correlated Electrons (cond-mat.str-el) | This paper has been withdrawn by the author due to an error in dealing with data | factual/methodological/other critical errors in manuscript | 987 |
1006.0046v5 | Some Aspects on Non-commutative Theories with a compactified Extra-Dimension | We study some aspects when one consider the existence of one extra-dimension in addition to a non-commutative space-time. We present here two different examples, where the first one provides a scenario were it is possible to relate the variations on the compactification radius $L$ and the non-commutative parameter $\theta^{\mu\nu}$, recovering the usual Minkowski $(3+1)D$ metric and, in the other one, we can set a simple relationship between this radius and $\theta$, the non-commutative parameter, for the gravitational potential between a point particle and a straight cosmic string in $(2+1)D$. | High Energy Physics - Theory (hep-th) | This paper has been withdrawn by the author due to a error in the first initial hypothesis | factual/methodological/other critical errors in manuscript | 992 |
1006.0556v4 | Lower bounds for the spectral radii of adjacency operators on Baumslag-Solitar groups | We will use free probability techniques to find lower bounds for the spectral radii of the adjacency operators on the Caley graphs of some non-amenable Baumslag-Solitar groups with the standard generators. | Operator Algebras (math.OA) | The preprint is now withdrawn, because of an error in the technique. (Certain words were counted twice.) However, we are working on producing a correct argument and we are able to obtain a nontrivial lower bound | factual/methodological/other critical errors in manuscript | 996 |
1006.0944v2 | A note about levels and sublevels of algebras obtained by the Cayley-Dickson process | In this paper, \thinspace \thinspace we generalize the concepts of \thinspace level \thinspace and \thinspace sublevel of a composition algebra to algebras obtained by the Cayley-Dickson process. In 1967, R. B. Brown constructed, for every}$t\in \Bbb{N},${\small % \ a division algebra}$A_{t}${\small \ of dimension}$2^{t}${\small \ over the power-series field}$K\{X_{1},X_{2},...,X_{t}\}.\,${\small \ This gives us the possibility to construct a division algebra of \thinspace dimension \thinspace 2}$^{t}\,${\small and prescribed \thinspace level and sublevel \thinspace \thinspace 2}$^{k}${\small ,\thinspace \thinspace}$k,\,t\in \Bbb{% N}^{*}${\small \ and a division algebra of \thinspace dimension \thinspace}$% 2^{t}+1,t\in \Bbb{N}\,${\small and prescribed \thinspace level and sublevel}% $\,2^{k}+1,k\in \Bbb{N}.\,\medskip $ | Rings and Algebras (math.RA) | This paper has been withdrawn by the author due to some errors. A new version will be update soon | factual/methodological/other critical errors in manuscript | 998 |
1006.1533v2 | Hierarchy of Separability Conditions for Bipartite Systems | A new hierarchy of separability conditions for bipartite states is obtained. All the conditions in the hierarchy are necessary for separability. The conditions are expressed in terms of higher powers of the density operator of the bipartite system and the reduced density operators of the subsystems. Violation of any of the conditions in the hierarchy implies entanglement. As a consequence of the hierarchy, another separability condition, expressed in terms of the eigenvalues of the density operators of the total system and subsystems, is obtained. | Quantum Physics (quant-ph) | Withdrawn due to a serious error in derivation of the main result | factual/methodological/other critical errors in manuscript | 1,006 |
1006.1733v2 | Non-Additivity of Minimum Output p-$\mathbf{R\acute{e}nyi}$ Entropy | Hastings disproved additivity conjecture for minimum output entropy by using random unitary channels. In this note, we employ his approach to show that minimum output $p-$Rényi entropy is non-additive for $p\in(0,p_0)\cup(1-p_0,1)$ where $p_0\approx 0.2855$. | Quantum Physics (quant-ph) | This paper has been withdrawn by the author due to a crucial error | factual/methodological/other critical errors in manuscript | 1,008 |
1006.2189v2 | Smoothing theory revisited | We give a concise proof of the fundamental theorem of smoothing theory in the special case when a smoothing exists. | Algebraic Topology (math.AT) | This paper has been withdrawn by the authors. The proof of the verification of axiom 1 for the smoothing functor that is given in the paper is false, since it would violate what is known in dimension 4. If U is a subset of V and both are diffeomorphic to R^4, then the restriction map of smoothing spaces sm(V) -> sm(U) need not be one-to-one on path components. Thus axiom 1 is violated in dimension 4. The verification of axiom 1 in higher dimensions is probably a consequence of the product structure theorem | factual/methodological/other critical errors in manuscript | 1,014 |
1006.2511v2 | Contact geometry and the Poincaré conjecture | We give a simple proof of the Poincaré conjecture by using the contact Ricci flow associated with the Reeb vector field. | General Mathematics (math.GM) | This paper has been withdrawn by the author due to a serious gap in defining contact Ricci flow | factual/methodological/other critical errors in manuscript | 1,023 |
1006.2513v2 | On the Achievability of Cramér-Rao Bound In Noisy Compressed Sensing | Recently, it has been proved in [Babadi et. al., 2009] that in noisy compressed sensing, a joint typical estimator can asymptotically achieve the Cramér-Rao lower bound of the problem. To prove this result, [Babadi et. al., 2009] used a lemma, which is provided in [Akackaya et. al., 2008], that comprises the main building block of the proof. This lemma contains a mathematical mistake in its statement and proof which should be corrected. One wonders then whether or not the main results of [Babadi et. al., 2009] are correct. In this correspondence, we will first explain the mistake in the mentioned lemma in [Akackaya et. al., 2008] and will then state a new correct form of it. Then we re-study the main results of [1], and we will show that fortunately they remain valid, that is, the Cramér-Rao bound in noisy compressed sensing is achievable and a joint typical estimator can achieve it. | Information Theory (cs.IT) | This paper has been withdrawn by the author due to a crucial error in it, when talking about a mistake in [Akackaya et. al., 2008], which was indeed correct | factual/methodological/other critical errors in manuscript | 1,024 |
1006.2549v2 | An inequality for Diophantine exponents in the case of simultaneous approximation | In this paper we prove an inequality for individual and uniform Diophantine exponents in the case of simultaneous approximation. This inequality is better than Jarnik's for small values of the uniform exponent. | Number Theory (math.NT) | This paper has been withdrawn by the author because a better estimate exists than the one proven in the paper | factual/methodological/other critical errors in manuscript | 1,028 |
1006.2622v2 | Time symmetric Bloch-Nordsieck infrared cancellation | It is usually assumed that the infrared divergences that occur for virtual photons in Feynman diagrams cancel against the corresponding divergences in phase space integrals for the emission of real soft photons. If this were the case then why do the corresponding phase space integrals for the absorption of real soft photons not diverge too, as one might expect on grounds of time-reversal symmetry, and if so what cancels these divergences? We show that this apparent time asymmetry is an artifact of the way that the diagrams are calculated, and we introduce a procedure for such calculations that is manifestly time symmetric. Moreover, we show that it is not mathematically meaningful to distinguish arbitrarily soft massless particles of positive and negative energy. | High Energy Physics - Phenomenology (hep-ph) | This paper has been withdrawn by the author due to a crucial error in equation 2.6 | factual/methodological/other critical errors in manuscript | 1,030 |
1006.2655v2 | A Reciprocity Result for Projective Indecomposable Modules of Cellular Algebras and BGG Algebras | We show that an adaptation of Landrock's Lemma for symmetric algebras also holds for cellular algebras and BGG algebras. This is a result relating the radical layers of any two projective modules. The reason it holds in our setting is that there is a duality between injective hulls and projective hulls. We then specify to $(q)$-Schur algebras, in this setting there are applications to tilting modules. The results of Jantzen then give us a reciprocity for the Loewy structure of tilting modules from the fundamental alcove in terms of the Loewy structure of lighter Weyl modules. | Representation Theory (math.RT) | This paper has been withdrawn due to problems with the result on rigidity | factual/methodological/other critical errors in manuscript | 1,031 |
1006.3161v5 | Comparison of Variations of Statistical and Wald's Entropies | We write the variation of the statistical entropy of matter fields outside a black hole along a Killing vector. This is done for generalized theories of gravity, using a Lie derivative and identification of the energy momentum tensor. | General Relativity and Quantum Cosmology (gr-qc) | This paper has been withdrawn by the authors due to an error that led to incorrect conclusions | factual/methodological/other critical errors in manuscript | 1,037 |
1006.3184v2 | A simple proof of the generalized strong recurrence for any non-zero parameter | The strong recurrence is equivalent to the Riemann hypothesis. In the present paper, we give a simple proof of the generalized strong recurrence for all non-zero parameters. | Number Theory (math.NT) | This paper has been withdrawn by the author. 3 pages. The proof has a gap. It is possible to avoid this, but then the proof becomes not simple | factual/methodological/other critical errors in manuscript | 1,038 |
1006.3301v2 | Codebook-Based SDMA for Coexistence with Fixed Wireless Service | A portion of frequency band for International Mobile Telecommunications (IMT)-Advanced is currently allocated to Fixed Wireless Service (FWS) such as Fixed Service (FS), Fixed Satellite Service (FSS), or Fixed Wireless Access (FWA), which requires frequency sharing between both the systems. SDMA, due to its high throughput nature, is candidate for IMT-Advanced. This paper proposes a systematic design of a precoder codebook for SDMA sharing spectrum with existing FWS. Based on an estimated direction angle of a victim FWS system, an interfering transmitter adaptively constructs a codebook forming a transmit null in the direction angle while satisfying orthogonal beamforming constraint. We derive not only asymptotic throughput scaling laws, but also an upperbound on throughput loss to analyze performance loss of the proposed SDMA relative to the popular SDMA called per-user unitary rate control (PU2RC). Furthermore, we develop a method of evaluating protection distance in order to analyze the spectrum sharing performance of the proposed approach. The simulation results of protection distance confirm that the proposed SDMA efficiently shares spectrum with FWS systems by reducing protection distance to more than 66%. Although our proposed SDMA always has lower throughput compared to PU2RC in non-coexistence scenario, it offers an intriguing opportunity to reuse spectrum already allocated to FWS. | Information Theory (cs.IT) | The paper has been withdrawn by the author due to some error in main analysis | factual/methodological/other critical errors in manuscript | 1,040 |
1006.3569v2 | Correlated dynamics of inclusions in a supported membrane | The hydrodynamic theory of heterogeneous fluid membranes is extended to the case of a membrane adjacent to a solid substrate. We derive the coupling diffusion coefficients of pairs of membrane inclusions in the limit of large separation compared to the inclusion size. Two-dimensional compressive stresses in the membrane make the coupling coefficients decay asymptotically as $1/r^2$ with interparticle distance $r$. We have calculated the effect of inclusions on the response of the membrane and the associated corrections to the coupling diffusion coefficients to leading order in the concentration of inclusions. While at short distances the response is modified as if the membrane were a two-dimensional suspension, the large-distance response is not renormalized by the inclusions. | Soft Condensed Matter (cond-mat.soft) | This paper has been withdrawn due to an error | factual/methodological/other critical errors in manuscript | 1,042 |
1006.3869v2 | Galois groups of multivariate Tutte polynomials | The multivariate Tutte polynomial of a graph is a generalisation of the two-variable version, obtained by assigning a variable to each edge of the graph. It has been shown that a graph G is 2-connected if and only if it has an irreducible Tutte polynomial. In this paper we prove that the Galois group of the multivariate Tutte polynomial of such a graph (over the field of functions in the edge variables) is the symmetric or alternating group of degree n-1, where n is the order of G. We also provide a partial proof of the conjecture that only the symmetric group can appear. | Combinatorics (math.CO) | This paper has been provisionally withdrawn due to a possible major error in Proposition 7 | factual/methodological/other critical errors in manuscript | 1,045 |
1006.3965v2 | A New Formula for the Inverse Wavelet Transform | Finding a computationally efficient algorithm for the inverse continuous wavelet transform is a fundamental topic in applications. In this paper, we show the convergence of the inverse wavelet transform. | Functional Analysis (math.FA) | This paper has been withdrawn by the author due to a crucial mistake | factual/methodological/other critical errors in manuscript | 1,046 |
1006.3987v2 | On entropic uncertainty relations for position and momentum | In [1][2] uncertainty relations for position and momentum are expressed in the form of inequalities involving Shannon and Rényi entropies for measuring processes with finite resolution. We show that these inequalities do not hold in general. A new sharp lower bound of entropies is given. | Quantum Physics (quant-ph) | This paper has been withdrawn by the author due to a crucial sign error | factual/methodological/other critical errors in manuscript | 1,048 |
1006.4003v2 | Spin transfer torque enhancement in dual spin valve in the ballistic regime | The spin transfer torque in dual spin valve, in which two antiparallelly aligned pinned ferromagnetic layers are on the two sides of a free ferromagnetic layer with two thin nonmagnetic spacers in between, is studied in the ballistic regime. We first present a physical picture to argue that, similar to the results in the diffusion regime, the spin transfer torque is dramatically enhanced in comparison to that in a conventional spin valve although no spin accumulation exists at the magnetic-nonmagnetic interfaces. Then, following Slonczewski's approach, we derive the analytical formula of the torque acting on the free magnetic layer when all magnetic layers are perfect polarizers. Depending on the orientation of free layer and the polarization degree of electrons, the spin transfer torque enhancement can reach a factor of a few tens. The general cases when transmission and reflection probabilities of free layer are different from zero or one are also numerically calculated. | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | This paper has been withdrawn by the author due to crucial statement error | factual/methodological/other critical errors in manuscript | 1,049 |
1006.4061v3 | Electric-triple-layer model based AC electroosmosis flow | The paper presents an novel electric triple layer(ETL) model as an improved model of electrical double layer(EDL) to predict electroosmosis flow rate on the electrode surface at low frequency. The predicted slip velocity based on classical EDL theory is much higher than experimental results, and ETL model can account for this deviation. Cross-over frequency at which the maximum electroosmosis flow velocity occurs based on ETL model is a little bit higher than that predicted in EDL theory, but still in keeping with classical prediction. Influences of triple layer thickness and electrode surface roughness on electroosmosis flow are analyzed via simulation and theoretical analysis agrees with experimental data very well, proving its validity. | Classical Physics (physics.class-ph) | authors erro | factual/methodological/other critical errors in manuscript | 1,050 |
1006.4703v4 | A construction of universal secure network coding | We construct a universal secure network coding. Our construction just modifies the transmission scheme at the source node and works with every linear coding at an intermediate node. We relax the security criterion such that the mutual information between the message and the eavesdropped signal is sufficiently small instead of strictly zero. Our construction allows the set of eavesdropped links to change at each time slot. | Information Theory (cs.IT) | This paper has been withdrawn by the author. The proof technique in this paper does not ensure the existence of a coding scheme that is secure against all the eavesdropping matrices of rank less than or equal to μ, which means that the proof does not prove the universal security as originally claimed. A much extended and corrected version of this paper was registered as arXiv:1102.3002. The author appreciates the helpful comment by Dr. [REDACTED-NAME] | factual/methodological/other critical errors in manuscript | 1,065 |
1006.5047v2 | Cognitive radio ad hoc networks (CRAHNs): Cognitive radio ad hoc networks (CRAHNs): Resource allocation techniques based on Bio-inspired computing | Spectrum is a scarce commodity, and considering the spectrum scarcity faced by the wireless-based service providers led to high congestion levels. Technical inefficiencies from pooled spectrum (this is nothing but the "common carrier principle" adopted in oil/gas/electricity pipelines/networks.), since all ad hoc networks share a common pool of channels, exhausting the available channels will force ad hoc networks to block the services. Researchers found that cognitive radio (CR) technology may resolve the spectrum scarcity. CR network proved to next generation wireless communication system that proposed as a way to reuse under-utilised spectrum of licensee user (primary network) in an opportunistic and non-interfering basis. A CR is a self-configuring entity in a wireless networking that senses its environment, tracks changes, and frequently exchanges information with their networks. Adding this layer of such intelligence to the ad hoc network by looking at the overall geography of the network known as cognitive radio ad hoc networks (CRAHNs). However, CRAHN facing challenges and condition become worst while tracks changes i.e. reallocation of another under-utilised channels while primary network user arrives. In this paper, channels or resource reallocation technique based on bio-inspired computing algorithm for CRAHN has been proposed. | Networking and Internet Architecture (cs.NI) | This paper has been withdrawn by the author due to a crucial sign error in equation 1 | factual/methodological/other critical errors in manuscript | 1,074 |
1006.5069v3 | Role of Antibodies: A Novel Paradigm in Mathematical Modeling for Cancer Treatment | A mathematical model for the quantitative analysis of cancer immune interaction, considering the role of antibodies has been proposed in this paper. The model is based on the clinical evidence, which states that antibodies can directly kill cancerous cells [1]. The existence of transcritical and saddle-node bifurcation, which has been proved using Sotomayor theorem, provides strong biological implications. Through numerical simulations, it has been illustrated that under certain therapy (like monoclonal antibody therapy), which is capable of altering the parameters of the system, cancer-free state can be obtained. | Quantitative Methods (q-bio.QM) | This paper has been withdrawn due to modeling error occurred because of wrong biological assumption | factual/methodological/other critical errors in manuscript | 1,075 |
1006.5198v6 | G. Birkhoff's problem in irreversible quantum dynamics | We study operator spaces determined uniquely by a completely positive map and find a complete invariance upto cocycle conjugacy for an extremal element in the convex set of unital trace preserving completely positive map on matrix algebra over the field of complex numbers. We prove a Hann-Banach-Arveson's type of theorem on operator spaces which made it possible to use dynamical systems approach to arrive at our main result via P. Jordan's theorem on order isomorphisms on $C^*$ algebras. | Functional Analysis (math.FA) | This paper has been withdrawn by the author as it needs substantial changes and some end results are wrong in its present form | factual/methodological/other critical errors in manuscript | 1,076 |
1006.5318v2 | Tripartite probability distributions and communication complexity | We show that every tripartite quantum correlation generated with a Schmidt state (in particular every correlation generated with the GHZ state) can be simulated with the sending of two bits of classical communication from Alice to Bob and Charlie plus the sending of two bits of classical communication from Bob to Charlie. This extends recent results which showed that the maximal violation of Bell inequalities attainable by these correlations is uniformly bounded. For simplicity, we state and prove the result for three parties, but the generalization to the case of $n$ parties follows easily. We also show that every $n$-partite probability distribution generated with local resources plus $c$-bits of local communication can violate a Bell inequality by at most a factor of $2^c$. | Quantum Physics (quant-ph) | This paper has been withdrawn by the authors. We believe the main result to be true, but the proof is not correct. We are at the moment trying to fix it | factual/methodological/other critical errors in manuscript | 1,079 |
1006.5534v2 | Seesaw Type I and III at the LHeC | We study the potential of testing the seesaw type I and III models at the LHeC, an e-p collision mode at the CERN collider. The e-p collision mode provides an excellent place to study lepton number violating process e^- p \to N j + X \to l^+ W^- j + X with W^- into hadron jets. Here N is a heavy Majorana neutrino and j is a hard hadron jet. With the electron energy E_e = 140 GeV and proton energy E_p = 7 TeV, we find that the cross section for the heavy neutrino N production can be as large as a few fb for the mass scale as high as 1 TeV, higher than what can be achieved by the p-p collision mode of LHC with the same related heavy neutrino couplings. | High Energy Physics - Phenomenology (hep-ph) | This paper has been withdrawn by the author due to some error in section 3.3, and should be recalculated | factual/methodological/other critical errors in manuscript | 1,082 |
1006.5757v4 | Concerning the searches for Higgs bosons | The great successes achieved by the Standard Model(SM) lead us to believe the existence of the Higgs particle. On the other hand, there are many evidences indicate that some unknown dark matter particle must exist in our universe. To identify the Higgs boson as the dark matter particle is difficult in the present SM, the challenge is: the Higgs particle is unstable while the dark matter particle is stable. A solution of this problem is proposed in this paper. We will describe a model in which almost all the predictions made by the present SM remain unchanged but leave two neutral stable Higgs particles, which may be the dark matter particle. Some possible experimental tests of Higgs particle are also suggested in this paper. | General Physics (physics.gen-ph) | This paper has been withdrawn by the author, because the idea of this paper is wrong | factual/methodological/other critical errors in manuscript | 1,088 |
1007.0181v2 | Higher congruence companion forms | For a rational prime $p \geq 2$ we consider $p$-ordinary, normalised eigenforms $f$ with associated $p$-adic Galois representations $\rho_f$ and $\mod{p^n}$ reductions $\rho_{f,n}$. We use deformation theory and modularity lifting to show that if the restriction of $\rho_{f,n} $ to a decomposition group $G_p$ splits then $f$ has a companion form $g$ modulo $p^n$ in the sense that $\rho_{f,n}$ and $\rho_{g,n}$ satisfy a certain congruence property. Using these higher congruence companion forms, we reformulate a deep question about the equivalence between $\rho_f|G_p$ being split and $f$ having complex multiplication. The reformulation is particularly useful because it makes the question amenable to analysis by computational tools. | Number Theory (math.NT) | Errors noticed and corrected. Will put up new version shortly | factual/methodological/other critical errors in manuscript | 1,093 |
1007.0230v2 | Neumann spectral cluster estimates outside convex obstacles | This paper concerns spectral clusters of the Neumann Laplacian on compact Riemannian manifolds with strictly geodesically concave boundary. We prove an inequality which controls the $L^p$ norms of spectral clusters. | Analysis of PDEs (math.AP) | This paper has been withdrawn by the author due to a significant error | factual/methodological/other critical errors in manuscript | 1,094 |
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