Results 81 to 90 of about 109 (103)

Multi-hypercyclic operators are hypercyclic

Mathematische Zeitschrift, 2001
An operator \(T\) on a separable complex Hilbert space \(\mathcal H\) space is said to be hypercyclic if there is a vector \(x\) such that the orbit \(\{T^nx: n=0,1,\ldots\}\) is dense in \(\mathcal H\). An operator is said to be supercyclic if there is a vector \(x\) such that the scalar multiples of the elements in the orbit are dense in \(\mathcal H\
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Syndetically Hypercyclic Operators

Integral Equations and Operator Theory, 2005
A sequence \((T_n)_{n\geq 0}\) of bounded operators on a separable \(\mathcal{F}\)-space \(X\) is hypercyclic if there exists a vector \(x\) in \(X\) such that the set \(\{T_n x \; ; \; n\geq 0\}\) is dense in \(X\). An operator \(T\) on \(X\) is hypercyclic if the sequence \((T^n)_{n\geq 0}\) of its powers is hypercyclic.
Peris, Alfredo, Saldivia, Luis
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A hypercyclic illusion

Journal of Theoretical Biology, 1988
Demonstration du caractere errone d'un modele de croissance de la paroi cellulaire des ...
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Codons and Hypercycles

Origins of life and evolution of the biosphere, 1999
Several hypotheses on the origin of codon assignments imply that the present protein synthesizing machinery was already in place when the assignments were made. These are examined by computer modeling. The results do not suggest that assignments were optimized for resistance to reading and mutation errors, nor that the assignments are random.
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Hypercycles, parasites and packages

Journal of Theoretical Biology, 1980
Abstract The hypercycle model considers a functional rather than spatial coupling of primitive tRNA molecules the essential phenomenon at the origin of life. We will critically discuss this model with special regard to the problems of selecting for functionally improved mutant molecules.
C, Bresch, U, Niesert, D, Harnasch
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Growth of hypercyclic functions: a continuous path between $\mathcal{U}$-frequent hypercyclicity and hypercyclicity

Proceedings of the Edinburgh Mathematical Society
AbstractWe are interested in the optimal growth in terms of Lp-averages of hypercyclic and $\mathcal{U}$-frequently hypercyclic functions for some weighted Taylor shift operators acting on the space of analytic functions on the unit disc. We unify the results obtained by considering intermediate notions of upper frequent hypercyclicity between ...
Mouze, Augustin, Munnier, Vincent
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Common Hypercyclic Vectors and the Hypercyclicity Criterion

Integral Equations and Operator Theory, 2009
An operator on a separable, infinite dimensional Banach space satisfies the Hypercyclicity Criterion if and only if the associated left multiplication operator is hypercyclic; see [14], [16], [29]. By examining paths of operators where each operator along the path satisfies the criterion, we provide necessary and sufficient conditions for a path of ...
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Hypercycles

1994
Abstract We now return to the problem last mentioned in Chapter 2: how can we devise a model in which more information than that contained in single 100-base RNA molecules can be maintained over many generations? There are two main approaches that have been taken to this problem.
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Frequently Hypercyclic Taylor Shifts

Computational Methods and Function Theory, 2016
Let \(\mathbb {C}_{\infty}\) be the extended complex plane endowed with the spherical metric. Assume that \(\Omega\subset \mathbb {C}_{\infty}\) is an open set and \(0\in \Omega.\) Denote by \(H(\Omega)\) the set of holomorphic functions on \(\Omega\) (vanishing at infinity in case \(\infty \in \Omega\)) endowed with the topology of uniform convergence
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Hypercyclic algebras

2018
We prove the existence of algebras of hypercyclic vectors in three cases: convolution operators, composition operators, and backward shift operators.
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