From Peter Lavers
Amanda Gefter’s exploration of infinity, mathematics and physics (17 August, p 32) arouses my bewilderment that people believe mathematical constructs like infinity are realised in the world. Where theory predicts infinite density, I see a breakdown of the theory.
Mathematical concepts don’t need to be part of physical reality. I can conceive of always being able to add another pebble to a pile of pebbles while recognising that it is practically impossible to do so.
Removing infinity from a particular cosmological theory is interesting as a way to overcome the problems arising from it, but it does not follow that infinity or similar constructs should be removed from mathematics.
Canberra, ACT, Australia
