P T-symmetric strings

PAOLO AMORE; FRANCISCO M. FERNÁNDEZ; JAVIER GARCÍA; G. GUTIERREZ

ANNALS OF PHYSICS (NEW YORK)

ACADEMIC PRESS INC ELSEVIER SCIENCE

Lugar: Amsterdam; Año: 2014 vol. 343 p. 61 - 71

0003-4916

line"> <We study both analytically and numerically the spectrum ofinhomogeneous strings with P T-symmetric density. We discussan exactly solvable model of P T-symmetric string which isisospectral to the uniform string; for more general strings, wecalculate exactly the sum rules Z(p) ≡ ∞n=1 1/Enp, with p =1, 2, . . . and find explicit expressions which can be used toobtain bounds on the lowest eigenvalue. A detailed numericalcalculation is carried out for two non-solvable models dependingon a parameter, obtaining precise estimates of the critical valueswhere pair of real eigenvalues become complex.