Time is a fundamental concept in both physics and philosophy, and it is therefore a natural subject for investigation by someone who attempts to bridge these two disciplines. Professor Shimony, a physicist and philosopher of science, is investigating three topics about time. The first is to lay down criteria for the proper measurement of time intervals. This problem has been extensively studied by the school called "Protophysics," but some of the doctrines of this school will be criticized -- particularly that measurement that measurement criteria should precede the formulation of dynamical laws. Professor Shimony argues that these criteria must be formulated in tandem with dynamic, as Newton implicitly does in the "Principia." The second investigation concerns "becoming" or "the transient now." It is commonly maintained by philosophers of science that the"nowness" of an event or a moment is merely subjective, and an old argument by McTaggart to this effect is cited. Professor Shimony will answer this argument by modifying and generalizing the classical Kantian thesis the "existence" in not a property. The third investigation is about the many different "arrows of time" that have been distinguished -- that of the psychological time sense, that of the second law of thermodynamics, that of the expanding universe, that of outgoing radiation from a source, and others. Professor Shimony is developing a thesis that the fundamental "arrow" is that of the actualization of quantum mechanical potentialities (of which a special case is the outcome of measurement of an indefinite quantity). This thesis requires a modification of the standard quantum dynamics, probably by adding a stochastic term to the time-dependent Schrodinger equation. In this way irreversibility will be inserted into the fundamental dynamics of physics, and it will be accomplished in a way that attributes objectivity to becoming.
