178 research outputs found

    Geometric Phase Integrals and Irrationality Tests

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    Let F(x)F(x) be an analytical, real valued function defined on a compact domain B⊂R\mathcal {B}\subset\mathbb{R}. We prove that the problem of establishing the irrationality of F(x)F(x) evaluated at x0∈Bx_0\in \mathcal{B} can be stated with respect to the convergence of the phase of a suitable integral I(h)I(h), defined on an open, bounded domain, for hh that goes to infinity. This is derived as a consequence of a similar equivalence, that establishes the existence of isolated solutions of systems equations of analytical functions on compact real domains in Rp\mathbb{R}^p, if and only if the phase of a suitable ``geometric'' complex phase integral I(h)I(h) converges for h→∞h\rightarrow \infty. We finally highlight how the method can be easily adapted to be relevant for the study of the existence of rational or integer points on curves in bounded domains, and we sketch some potential theoretical developments of the method

    The New Publishing Scene and the Tenure Case: An Administrator’s View

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    Stem-Like Adaptive Aneuploidy and Cancer Quasispecies

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    We analyze and reinterpret experimental evidence from the literature to argue for an ability of tumor cells to self-regulate their aneuploidy rate. We conjecture that this ability is mediated by a diversification factor that exploits molecular mechanisms common to embryo stem cells and, to a lesser extent, adult stem cells, that is eventually reactivated in tumor cells. Moreover, we propose a direct use of the quasispecies model to cancer cells based on their significant genomic instability (i.e. aneuploidy rate), by defining master sequences lengths as the sum of all copy numbers of physically distinct whole and fragmented chromosomes. We compute an approximate error threshold such that any aneuploidy rate larger than the threshold would lead to a loss of fitness of a tumor population, and we confirm that highly aneuploid cancer populations already function with aneuploidy rates close to the estimated threshold

    Entire slice regular functions

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    Entire functions in one complex variable are extremely relevant in several areas ranging from the study of convolution equations to special functions. An analog of entire functions in the quaternionic setting can be defined in the slice regular setting, a framework which includes polynomials and power series of the quaternionic variable. In the first chapters of this work we introduce and discuss the algebra and the analysis of slice regular functions. In addition to offering a self-contained introduction to the theory of slice-regular functions, these chapters also contain a few new results (for example we complete the discussion on lower bounds for slice regular functions initiated with the Ehrenpreis-Malgrange, by adding a brand new Cartan-type theorem). The core of the work is Chapter 5, where we study the growth of entire slice regular functions, and we show how such growth is related to the coefficients of the power series expansions that these functions have. It should be noted that the proofs we offer are not simple reconstructions of the holomorphic case. Indeed, the non-commutative setting creates a series of non-trivial problems. Also the counting of the zeros is not trivial because of the presence of spherical zeros which have infinite cardinality. We prove the analog of Jensen and Carath\'eodory theorems in this setting

    Positivity, rational Schur functions, Blaschke factors, and other related results in the Grassmann algebra

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    We begin a study of Schur analysis in the setting of the Grassmann algebra, when the latter is completed with respect to the 11-norm. We focus on the rational case. We start with a theorem on invertibility in the completed algebra, and define a notion of positivity in this setting. We present a series of applications pertaining to Schur analysis, including a counterpart of the Schur algorithm, extension of matrices and rational functions. Other topics considered include Wiener algebra, reproducing kernels Banach modules, and Blaschke factors.Comment: 35 page

    Regular Functions on the Space of Cayley Numbers

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    In this paper we present a new definition of regularity on the space Ç of Cayley numbers (often referred to as octonions), based on a Gateaux-like notion of derivative. We study the main properties of regular functions, and we develop the basic elements of a function theory on Ç. Particular attention is given to the structure of the zero sets of such functions

    On a Generalization of the Corona Problem

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    Let g, fl,...., fm EH (A). We provide conditions on fl,...,fm in order that Ig(z) lIfi(z)l+...+Ifm (z)I, for all z in 4, imply that g, or g2, belong to the ideal generated by fl,....,fm in H

    A Sheaf Theoretic Approach to Consciousness

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    A new fundamental mathematical model of consciousness based on category theory is presented. The model is based on two philosophical-theological assumptions: a) the universe is a sea of consciousness, and b) time is multi-dimensional and non-linear
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