The elastic shell T‐matrix theory evaluated

The T‐matrix method initiated by Waterman was extended in a clever paper by Peterson and the Varadans in 1980 to the complicated problem of elongated elastic shells. There have been some questions on whether the method converges for thin shells due to the impression that one must be able to inscribe a spherical surface in the annular region of the shell. The method may be derived by making use of several of the constraining equations that arise naturally and we show that the expression derived in 1980 is generally correct at least for objects with mirror symmetry. We present some details of the theoretical development with some calculations.