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“David Park is a physicist and philosopher at Williams College in Massachusetts with a lifelong interest in a time which he too thinks doesn't pass. For Park, the passage of time is not so much an illusion as a myth, "because it involves no deception of the senses.... One cannot perform any experiment to tell unambiguously whether time passes or not." This is certainly a telling argument. After all, what reality can be attached to a phenomenon that can never be demonstrated experimentally? In fact, it is not even clear how to think about demonstrating the flow of time experimentally. As the apparatus, laboratory, experimenter, technicians, humanity generally and the universe as a whole are apparently caught up in the same inescapable flow, how can any bit of the universe be "stopped in time" in order to register the flow going on in the rest of it? It is analogous to claiming that the whole universe is moving through space at the same speed—or, to make the analogy closer, that space is moving through space. How can such a claim ever be tested?”
― Paul Davies, About Time: Einstein's Unfinished Revolution

“Until now, I've been writing about "now" as if it were literally an instant of time, but of course human faculties are not infinitely precise. It is simplistic to suppose that physical events and mental events march along exactly in step, with the stream of "actual moments" in the outside world and the stream of conscious awareness of them perfectly synchronized. The cinema industry depends on the phenomenon that what seems to us a movie is really a succession of still pictures, running at twenty-five [sic] frames per second. We don't notice the joins. Evidently the "now" of our conscious awareness stretches over at least 1/25 of a second.

In fact, psychologists are convinced it can last a lot longer than that. Take he familiar "tick-tock" of the clock. Well, the clock doesn't go "tick-tock" at all; it goes "tick-tick," every tick producing the same sound. It's just that our consciousness runs two successive ticks into a singe "tick-tock" experience—but only if the duration between ticks is less than about three seconds. A really bug pendulum clock just goes "tock . . . tock . . . tock," whereas a bedside clock chatters away: "ticktockticktock..." Two to three seconds seems to be the duration over which our minds integrate sense data into a unitary experience, a fact reflected in the structure of human music and poetry.”
― Paul Davies, About Time: Einstein's Unfinished Revolution

“Perhaps there are many "nows" of varying duration, depending on just what it is we are doing. We must face up to the fact that, at least in the case of humans, the subject experiencing subjective time is not a perfect, structureless observer, but a complex, multilayered, multifaceted psyche. Different levels of our consciousness may experience time in quite different ways. This is evidently the case in terms of response time. You have probably had the slightly unnerving experience of jumping at the sound of a telephone a moment or two before you actually hear it ring. The shrill noise induces a reflex response through the nervous system much faster than the time it takes to create the conscious experience of the sound.

It is fashionable to attribute certain qualities, such as speech ability, to the left side of the brain, whereas others, such as musical appreciation, belong to processes occurring on the right side. But why should both hemispheres experience a common time? And why should the subconscious use the same mental clock as the conscious?”
― Paul Davies, About Time: Einstein's Unfinished Revolution

“Psychologists have devised some ingenious ways to help unpack the human "now." Consider how we run those jerky movie frames together into a smooth and continuous stream. This is known as the "phi phenomenon." The essence of phi shows up in experiments in a darkened room where two small spots are briefly lit in quick succession, at slightly separated locations. What the subjects report seeing is not a succession of spots, but a single spot moving continuously back and forth. Typically, the spots are illuminated for 150 milliseconds separated by an interval of fifty milliseconds. Evidently the brain somehow "fills in" the fifty-millisecond gap. Presumably this "hallucination" or embellishment occurs after the event, because until the second light flashes the subject cannot know the light is "supposed" to move. This hints that the human now is not simultaneous with the visual stimulus, but a bit delayed, allowing time for the brain to reconstruct a plausible fiction of what has happened a few milliseconds before.

In a fascinating refinement of the experiment, the first spot is colored red, the second green. This clearly presents the brain with a problem. How will it join together the two discontinuous experiences—red spot, green spot—smoothly? By blending the colors seamlessly into one another? Or something else? In fact, subjects report seeing the spot change color abruptly in the middle of the imagined trajectory, and are even able to indicate exactly where using a pointer. This result leaves us wondering how the subject can apparently experience the "correct" color sensation before the green spot lights up. Is it a type of precognition? Commenting on this eerie phenomenon, the philosopher Nelson Goodman wrote suggestively: "The intervening motion is produced retrospectively, built only after the second flash occurs and projected backwards in time." In his book Consciousness Explained , philosopher Daniel Dennett points out that the illusion of color switch cannot actually be created by the brain until after the green spot appears. "But if the second spot is already 'in conscious experience,' wouldn't it be too late to interpose the illusory content between the conscious experience of the red spot and the conscious experience of the green spot?”
― Paul Davies, About Time: Einstein's Unfinished Revolution