Between Physics and Philosophy—Festschrift for Peter Mittelstaedt on His 80th Birthday

Abstract

On 24 November 2009, Peter Mittelstaedt celebrated his eightieth birthday. The contributions by his colleagues and students collected here in three consecutive issues of Foundations of Physics have been specially written to pay tribute to his scientific achievements. The articles written for this Festschrift reflect the breadth of Peter Mittelstaedt’s scientific oeuvre. Brigitte Falkenburg has contributed a review and appreciation of Peter Mittelstaedt’s philosophical work. Also included is a survey of his research in theoretical physics and the foundations of quantum mechanics, which may serve as a guide to the enclosed bibliography of his publications. “Between Physics and Philosophy” is the title of a two-day Symposion that was held in his honor at the University of Cologne in December 2009. Under this title we celebrated Peter Mittelstaedt as one of a small number of distinguished scholars who have successfully maintained the spirit and practice of physics as natural philosophy. Creatively crossing the boundary between physics and philosophy, he has helped to build bridges connecting these disciplines much to their mutual benefit. A Festschrift Editorial entitled “Peter Mittelstaedt—Philosopher–Physicist”, written for this journal in 1989 on the occasion of his sixtieth birthday, concluded with the sentence: “Foundations of physics, a delicate orchid among the firm and well-established branches of physics, will be a fortunate beneficiary indeed of his undiminished support and inspiration in the future.” This sentence has come true indeed—Peter Mittelstaedt has continued to be highly productive, looking back now at an astounding time span of 55 years as an active researcher, always maintaining exemplary standards of intellectual rigor, clarity and depth in his scientific writing. The delicate orchid that Foundations of Quantum Mechanics used to be then has now grown into a strong and flourishing branch of fundamental physics, not least through