In a Commentary in the July 2012 issue of Physics Today, I maintain that stubborn problems in the interpretation of quantum mechanics melt away if one takes literally Niels Bohr's dictum that the purpose of science is not to reveal “the real essence of the phenomena” but to find “relations between the manifold aspects of our experience” [1].

This same view of science, that it is a tool each of us uses to organize our own experience, also disposes of the vexing but entirely classical problem of “the Now.” Rudolf Carnap states the problem succinctly in his report of a conversation with Albert Einstein:

The issue here is not, as you might think, that the simultaneity of events in different places depends on frame of reference. Events whose temporal ordering is ambiguous relative to an event that I experience Now are irrelevant, because they are outside the backward and forward light cones of my Now and cannot affect or be affected by what I experience Now. Whether or not I choose to regard them as contemporary with my Now is entirely a matter of personal convention. The actual issue is that physics seems to have nothing whatever to say about the Now even at a single place, but deals only with relations between one time and another, in spite of the fact that the present moment is immediately evident as such to each and every one of us.

Any person's Now is a special event for that person as it is happening. By an “event” I mean an experience whose duration and location are restricted enough that it can usefully be represented as a point in space and time. My Now is distinguished from other events I have experienced by being the actual current state of affairs. I can distinguish it from earlier events (former Nows) that I merely remember and from later events that I can only imagine. My remembered past terminates in my Now.