String theory, the crisis in particle physics and the ascent of metaphoric arguments

This essay presents a critical evaluation of the concepts of string theory and its impact on particle physics. The point of departure is a historical review of four decades of string theory within the broader context of six decades of failed attempts at an autonomous S-matrix approach to particle theory. The central message, contained in sections 5 and 6, is that string theory is not what its name suggests, namely a theory of of objects in spacetime whose localization is string- instead of point-like. Contrary to popular opinion the oscillators corresponding to the Fourier models of a quantum mechanical string do not cause a stringlike spatial extension of the object under discussion and neither does the "range space" of a chiral conformal QFT acquire the interpretation of string-like localized quantum matter. Rather the superstring represents a solution of a problem which enjoyed some popularity in the 60s: the construction of infinite component wave function with a (realistic) mass/spin spectrum. The mass/spin tower "sits" over one point and does not arise from a string in spacetime. The widespread acceptance of a theory whose interpretation has been based on metaphoric reasoning had a corroding influence on particle theory, a point which will be illustrated in the last section with some remarks of a more sociological nature.