## Friday, November 03, 2006

### Kingdom Thermodynamics 3: The Boundaries

I followed the introduction to this series with a discussion of the principle of causality, and how it underlies the Second Law of Thermodynamics but is also inconsistent with Christian theology. In this third post I want to look at a different, but in some way equivalent, way in which the Second Law is in tension with theology. This relates to assumptions about what happens at boundaries, especially those at the beginning and the end of time.

The point which I am trying to make is rather clearer when presented in terms of space rather than of time. So I will start with what is I hope a simple analogy, so that those of you who are not used to too much technical material can get an idea of what I am talking about.

First imagine a large flag, flying in a gentle breeze. At one end the flag is fixed, tied to a flagpole, and can move only if the flagpole moves. The other end of the flag is flying free, with no immediate constraints. The middle of the flag is partially free, but not completely so because it cannot move too far from the pole. A point on the flag say one tenth of its width from the pole is even less free, because it is constrained to be close to the pole.

Then imagine a large banner of the kind which is fixed at each end to a pole, but is being carried so that it is loose in the middle. In this case both ends of the banner are fixed. The middle of the banner is relatively free, but it is constrained to some extent, to an equal extent, by both poles, for it cannot move too far from either of them. As for a point on the banner one tenth of its width from one pole, this is again quite tightly constrained by the nearby pole; there is also some constraint from the second pole, but this is much less tight.

Then try to imagine this same kind of situation transformed from space into time. This is rather hard. Perhaps one can imagine a group of children who are released from school to explore an area on condition that they all get home at a particular time - and imagine that they are actually obedient! As you watch how they spread out across the area, to start with this will be determined by their starting point and how fast they walk or run. As time goes on they will start to realise that they mustn't wander too far as they must get home on time, and so their distribution will start to be affected by this. As they start to return, a time will come when their positions are determined by their need to get home, and hardly at all by where they started from.

Or imagine a dynamic caption of the type I have sometimes seen on TV programmes. It starts with a clear message, and then gradually and apparently at random letters in the message start to change until it becomes unreadable. For a time it looks as if nothing but chaos remains. But it gradually becomes apparent that a new message is forming. The changes turn out not to have been random at all, but to have been constrained by the intention to transform the message letter by letter into a new message.

All of these are examples of boundary conditions. In the case of the flag, the boundary conditions in space apply at one edge only, whereas there are no conditions at the other edge; but for the banner the boundary conditions apply at both edges. For the children, there is an initial boundary condition and also a final boundary condition, that they are in a particular place at a particular time. Similarly, there are initial and final conditions on the letters on the TV screen, that they form particular messages at the start and at the end. If you look at a point in space or time which is close to a boundary with conditions, the state at this point is constrained closely by the boundary conditions, but the constraints become much looser a long way from the boundary.

When we look at processes in time in the world as we know it, at least those which are not somehow controlled by intelligence and advance planning, it seems that no final boundary conditions can apply, although initial boundary conditions may be imposed. Thus processes in time are more like the flag than the banner, with the end flying free. In practice we can constrain the final state of something in time only by imposing tight initial boundary conditions, or by intelligent intervention. This is a direct consequence of causality operating within the universe, which implies that the state of something at the end of a period cannot affect any state or event during that period.

However, when we look at all of this from a biblical and theological perspective, the position is quite different. The Bible gives clear teaching about the future, including specific prophecies, some of which have already been fulfilled, and details about the end times. If the future is known in any kind of absolute sense, that is to say if these prophecies are more than predictions based on current data (like weather forecasts), this is a final boundary condition and so a breach of the principle of causality.

Theologians have taken a variety of positions on specific prophecies. Those of a more liberal kind have tended to discount all biblical prophecy, and to take apparent fulfilment of prophecies, such as those in the book of Daniel, as evidence that the prophecy was in fact written after the event. Open theists have taken a rather different line: prophecies are not absolute knowledge of the future, but rather a combination of predictions based on current data and advance announcements of plans which God intends to fulfil by working within the universe and within time.

Of course any theologian who presupposes that the principle of causality is a philosophical absolute is bound to take one or other of these positions on prophecy. However, this does not seem to be the biblical picture, as I briefly explained in part 2 of this series. The biblical position, as it seems to me, is that God knows the future absolutely, and at times communicates information about it to humans as prophecy. He has said:
I make known the end from the beginning,
from ancient times, what is still to come.
I say, 'My purpose will stand,
and I will do all that I please.'
(Isaiah 46:10, TNIV)
This flow of definite information from the future to the present is a breach of causality. Furthermore, it is related to the spiritual gift of prophecy (although revelation of information about the future is only a small part of that gift), and as such is an indication of a link between the gifts of the Holy Spirit and breaches of the Second Law of Thermodynamics. I intend to explore this link further later in this series.

I do not intend in this series to discuss specific prophecies concerning events before the end of time. My interest here is more in the final state of the created universe, and how it compares with the initial state. As this post is already rather long, I will continue this discussion in the next post in this series.

Note: originally the next post was combined with this one; I then split them into two separate posts.