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20042022
most citedFrom genotypes to organisms: State-of-the-art and perspectives of a cornerstone in evolutionary dynamics

110 citations · 323 across the 20 of their papers we have counts for

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math.SP2020★ 2 cited

Nonconcavity of the Spectral Radius in Levinger's Theorem

Lee Altenberg, Joel E. Cohen

Let be a nonnegative irreducible square matrix and let be its spectral radius and Perron-Frobenius eigenvalue. Levinger asserted and sever…

math.SP2019

An Extension of the Rayleigh Quotient to the Spectral Radius of Asymmetric Nonnegative Matrices

Lee Altenberg

The Rayleigh quotient, which provides the classical variational characterization of the spectral radius of Hermitian matrices, can be extended to nonsymmetric nonnegative irreducib…

math.SP2013

On the Ordering of Spectral Radius Product r(A) r(AD) Versus r(A^2 D) and Related Applications

Lee Altenberg

For a nonnegative matrix A and real diagonal matrix D, two known inequalities on the spectral radius, r(A^2 D^2) >= r(AD)^2 and r(A) r(A D^2) >= r(AD)^2, leave open the question of…

math.SP2012★ 8 cited

A Sharpened Condition for Strict Log-Convexity of the Spectral Radius via the Bipartite Graph

Lee Altenberg

Friedland (1981) showed that for a nonnegative square matrix A, the spectral radius r(e^D A) is a log-convex functional over the real diagonal matrices D. He showed that for fully…

math.SP2011★ 66 cited

Resolvent Positive Linear Operators Exhibit the Reduction Phenomenon

Lee Altenberg

The spectral bound, s(a A + b V), of a combination of a resolvent positive linear operator A and an operator of multiplication V, was shown by Kato to be convex in b \in R. This is…

math.SP2010★ 5 cited

Karlin Theory On Growth and Mixing Extended to Linear Differential Equations

Lee Altenberg

Karlin's (1982) Theorem 5.2 shows that linear systems alternating between growth and mixing phases have lower asymptotic growth with greater mixing. Here this result is extended to…