164 research outputs found

    Divided difference operators in equivariant KKKK-theory

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    Let GG be a compact connected Lie group with a maximal torus TT. Let AA, BB be GG-Cβˆ—\mathrm{C}^\ast-algebras. We define certain divided difference operators on Kasparov's TT-equivariant KKKK-group KKT(A,B)KK_T(A,B) and show that KKG(A,B)KK_G(A,B) is a direct summand of KKT(A,B)KK_T(A,B). More precisely, a TT-equivariant KKKK-class is GG-equivariant if and only if it is annihilated by an ideal of divided difference operators. This result is a generalization of work done by Atiyah, Harada, Landweber and Sjamaar.Comment: 27 pages. arXiv admin note: text overlap with arXiv:0906.1629 by other author

    Derivations on four dimensional genetic Volterra algebra

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    In this paper, we describe all derivations on four dimensional genetic Volterra algebras. We show that any local derivation is a derivation of the algebra. It is a positive answer to a conjecture made by Ganikhodzhaev, Mukhamedov, Pirnapasov and Qaralleh

    K-theory of weight varieties

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    Let TT be a compact torus and (M,Ο‰)(M,\omega) a Hamiltonian TT-space. We give a new proof of the KK-theoretic analogue of the Kirwan surjectivity theorem in symplectic geometry by using the equivariant version of the Kirwan map introduced in one of R. Goldin's papers. We compute the kernel of this equivariant Kirwan map, and hence give a computation of the kernel of the Kirwan map. As an application, we find the presentation of the kernel of the Kirwan map for the TT-equivariant KK-theory of flag varieties G/TG/T where GG is a compact, connected and simply-connected Lie group. In the last section, we find explicit formulae for the KK-theory of weight varieties.Comment: 16 page

    Determinants containing powers of polynomial sequences

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    We derive identities for the determinants of matrices whose entries are (rising) powers of (products of) polynomials that satisfy a recurrence relation. In particular, these results cover the cases for Fibonacci polynomials, Lucas polynomials and certain orthogonal polynomials. These identities naturally generalize the determinant identities obtained by Alfred, Carlitz, Prodinger, Tangboonduangjit and Thanatipanonda.Comment: 12 page

    A remark on commutative subalgebras of Grassmann algebra

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    Let n=4k+1n=4k+1 and kβ‰₯4k\geq 4. We show that there exists maximal commutative subalgebras (with respect to inclusion) of dimension less that 3β‹…2nβˆ’23\cdot 2^{n-2}

    A Probabilistic Two-Pile Game

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    We consider a game with two piles, in which two players take turn to add aa or bb chips (aa, bb are not necessarily positive) randomly and independently to their respective piles. The player who collects nn chips first wins the game. We derive general formulas for pnp_n, the probability of the second player winning the game by collecting nn chips first and show the calculation for the cases {a,b}\{a,b\} = {βˆ’1,1}\{-1,1\} and {βˆ’1,2}\{-1,2\}. The latter case was asked by Wong and Xu \cite{WX}. At the end, we derive the general formula for pn1,n2p_{n_1,n_2}, the probability of the second player winning the game by collecting n2n_2 chips before the first player collects n1n_1 chips.Comment: 14 page

    Outlier Detection in High Dimensional Data

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    High-dimensional data poses unique challenges in outlier detection process. Most of the existing algorithms fail to properly address the issues stemming from a large number of features. In particular, outlier detection algorithms perform poorly on data set of small size with a large number of features. In this paper, we propose a novel outlier detection algorithm based on principal component analysis and kernel density estimation. The proposed method is designed to address the challenges of dealing with high-dimensional data by projecting the original data onto a smaller space and using the innate structure of the data to calculate anomaly scores for each data point. Numerical experiments on synthetic and real-life data show that our method performs well on high-dimensional data. In particular, the proposed method outperforms the benchmark methods as measured by the F1F_1-score. Our method also produces better-than-average execution times compared to the benchmark methods

    On Horadam quaternions by using matrix method

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    In this paper, we give several matrix representations for the Horadam quaternions. We derive several identities related to these quaternions by using the matrix method. Since quaternion multiplication is not commutative, some of our results are non-commutative analogues of the well known identities for the Fibonacci-like integer sequences. Lastly, we derive some binomial-sum identities for the Horadam quaternions as an application of the matrix method

    Some basic properties of the generalized bi-periodic Fibonacci and Lucas sequences

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    In this paper, we consider a generalization of Horadam sequence fwng which is defined by the recurrence relation wn = x(n)wn-1+ cwn-2; where x(n) = a if n is even, x(n) = b if n is odd with arbitrary initial conditions w0;w1 and nonzero real numbers a, b and c. As a special case, by taking initial conditions 0, 1 and 2, b we define the sequences {un} and {vn}, respectively. The main purpose of this study is to derive some basic properties of the sequences {un}, {vn} and {wn} by using matrix approach

    Game of Pure Chance with Restricted Boundary

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    We consider various probabilistic games with piles for one player or two players. In each round of the game, a player randomly chooses to add aa or bb chips to his pile under the condition that aa and bb are not necessarily positive. If a player has a negative number of chips after making his play, then the number of chips he collects will stay at 00 and the game will continue. All the games we considered satisfy these rules. The game ends when one collects nn chips for the first time. Each player is allowed to start with ss chips where sβ‰₯0s\geq 0. We consider various cases of (a,b)(a,b) including the pairs (1,βˆ’1)(1,-1) and (2,βˆ’1)(2,-1) in particular. We investigate the probability generating functions of the number of turns required to end the games. We derive interesting recurrence relations for the sequences of such functions in nn and write these generating functions as rational functions. As an application, we derive other statistics for the games which include the average number of turns required to end the game and other higher moments.Comment: 19 page
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