24. The Direction of Time
1. Two questions
a) Does time flow, or do we flow through time?
Let’s assume that we (the universe) flow through time; time is just there, like space, as a
dimension which we can occupy – which we do occupy successively
Then there is an interesting question about the direction in which we move through time
b) If we flow through time, could we be flowing in the other direction?
Could we have been going through it in the opposite direction? What tells us which direction we
are going in and which we are not?
2. A brief digression on physics
Most highlevel laws of physics are symmetrical to time
The only basic physical law that is not symmetrical with respect to time is the Second Law of
Thermodynamics: entropy increases with time
Entropy: extent to which the “smoothingout” process has occurred.
Entropy later in time is greater than entropy earlier in time
The Second Law of Thermodynamics just says that as time goes on the peaks of matter and
energy in the universe smooth out.
i.e. Spiky jagged mountains get rounded down, Crisp New Carpets get dull and ragged, Hotspots
in Bathtubs even out, Pristine books get tatty, Smooth Skin gets wrinkled, Concentrations of time
and energy even out.
The smoothingout process of objects, us, is what gives the direction of time
3. A question about the direction of time
Could there be a part of the universe where the smoothingout process is going in the other direction?
That is, a part where people (and their objects) are going through time in the opposite direction?
On a certain morning, in 1950, as dawn breaks and students gather at UWO, a colony of people
surrounded by a fence has appeared on the lawn in front of UC. What is bizarre about them going about
their business, they look like they are a film being played backwards. They don’t actually eat food; they
regurgitate food onto their plates, as if they had not eaten them. When they take a bath, they are clean and
as they pull the plug, dirty water comes up and they become dirty and the water goes up the spout.
That is not their reality; their reality is very much like ours except they experience it in