The End of Time: The Next Revolution in Physics

This, then, gives a genuine cause for our awareness of motion and the passing of time. The conscious mind, in any instant, is actually aware of a short segment of the ‘line of time’, along which there is an entropy gradient. Time seems to flow in the direction of increasing entropy. Interestingly, consciousness and understanding are always tied to a short time span, which was called the specious present by the philosopher and psychologist William James (brother of novelist Henry). The specious present is closely related to the phenomenon of short-term memory and our ability to grasp and understand sentences, lines of poems and snatches of melody. It has a duration of up to about three seconds.

The key element in Boltzmann’s idea is comparison of structures. There needs to be qualitative change in the brain patterns along a segment of the ‘line of time’. If the brain pattern in each instant is likened to a card, then the patterns become a pack of cards, and our conscious experience of time flow arises (somehow) from the change of pattern across the pack. Though we may not understand the mechanism, the effect does have a cause.

To summarize: Newtonian time is an abstract line with direction – from past to future. Boltzmann keeps the line but not the direction. That belongs to the ‘washing’. But do we need the line?

TIME WITHOUT TIME

Perhaps not. The brain often fools us. When we first look at certain drawings, they appear to represent one thing. After a while, the image flickers and we see something different. The reason is well understood: the brain processes information before we get it. We do not see things as they are but as the brain interprets them for us. There are very understandable reasons for this, but the fact remains that we are often fooled by such ‘deceptions’.

Could all motion be a similar deception? Suppose we could freeze the atoms in our brains at some instant. We might be watching gymnastics. What would brain specialists find in the frozen pattern of the atoms? They will surely find that the pattern encodes the positions of the gymnasts at that instant. But it may also encode the positions of the gymnasts at preceding instants. Indeed, it is virtually certain that it will, because the brain cannot process data instantaneously, and it is known that the processing involves transmission of data backwards and forwards in the brain. Information about the positions of the gymnasts over a certain span of time is therefore present in the brain in any one instant.

I suggest that the brain in any instant always contains, as it were, several stills of a movie. They correspond to different positions of objects we think we see moving. The idea is that it is this collection of ‘stills’, all present in any one instant, that stands in psychophysical parallel with the motion we actually see. The brain ‘plays the movie for us’, rather as an orchestra plays the notes on the score. I am not going to attempt to elaborate on how this might be done; all I want to do is get the basic idea across. There are two parts to it. First, each instantaneous brain pattern contains information about several successive positions of the objects we see moving in the world. These successive positions need correspond only to a smallish fraction of a second. Second, the appearance of motion is created by the instantaneous brain pattern out of the simultaneous presence of several different ‘images’ of the gymnasts contained within it (Figure 2). This happens independently of the earlier and later brain states.

Figure 2 My explanation of how it might be possible to ‘see’ motion when none is there is illustrated in this chronophotograph of a sideways jump. My assumption is that the pattern of the atoms in our brain encodes, at any instant, about six or seven images of the gymnast. The standard ‘temporal’ explanation is that the gymnast passes through all these positions in a fraction of a second. My idea is that when we think we are seeing actual motion, the brain is interpreting all the simultaneously encoded images and, so to speak, playing them as a movie.