Keynote presentation at TIME-97
---------
Title: Alternative conceptions of the time-line
It is often assumed that if time is continuous, then the standard
mathematical account of the continuum - the real line - is the appropriate
model of the local structure of the timeline. However, another popular
account of the timeline which provides the basis for Allen's famous 13
interval relations does not seem naturally compatible with the real line.
This talk sharpens the differences between these two accounts and offers a
unified account which retains some advantages of both, at the cost of
making the continuum a slightly more complicated structure. The end result,
which allows intervals to have negative and zero lengths, might be seen as
a re-invention of arithmetic.
-----------