The Structure of Space and Time

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Until the 20th century physicists by and large did not pay much attention to the structure of space and time. Physicists were for the most part interested in figuring out the structure of the physical contents of space and time, namely matter and fields, and the equations that govern their interaction and evolution. Space and time themselves were simply taken as an immutable background, one which Euclid already knew how to describe, and which did not require much further attention. With the advent of Relativity Theory in the early 20th Century this changed. According to General Relativity space-time interacts with its contents, and its structure is non-Euclidean. In fact, there are many other implications that modern physics has for the structure of space and time which have received less scrutiny. My book (Space and Time, and Stuff) will discuss the following ideas: the idea that time has no structure whatsoever, i.e. the idea that time consists of nothing but a collection of intrinsically unrelated snapshots; the idea that only the present exists; the idea that everything that is physically possible occurs somewhere in space and time; the idea that space and time are not physical objects but rather relations between physical events; the idea that properties are nothing but locations in structured spaces; the idea that one can dispense with mathematical objects by 'spatialising' the physical properties of objects, the idea that space and time do not contain minimal-sized points and instants but are infinitely divisible, the idea that the structure of space and time allows time travel in a perfectly consistent and clear manner, and, finally, the idea that anti-particles are nothing but particles that are traveling back in time. In fact, my book amounts to a fairly detailed investigation of a single unified topic, namely the structure of space and time. In each chapter I concentrate on a different feature of physics, and ask: what is the best fundamental account of this feature, and what consequences does this have for the structure of space and time?