Spectra that are Newton after extension or translation

M. Pisonero
C. R. Johnson, William & Mary
C. Marijuan


The appending of real numbers, and also conjugate pairs, to Newton spectra is studied to understand circumstances in which the Newton inequalities are preserved. Appending to a non-Newton spectrum to achieve the Newton inequalities is also studied. Finally the translations of Newton spectra that are Newton are also studied. A sample result is that any number of positive real numbers may be appended to a Newton spectrum, to retain the Newton property, when the Newton coefficients are positive, while any Newton spectrum may be made non-Newton by appending a conjugate pair with positive real part and sufficiently large imaginary part. (C) 2010 Elsevier Inc. All rights reserved.