Quote (Ylem122 @ May 7 2013 01:34am)
Non euclidian geometry is still based in the real world. its a matter of euclids 5th postualte and attempted to discern if the universe is governed by euclidian or non euclidian geometry.
it is not possible to decide through mathematical reasoning alone if the geometry of the physical universe is Euclidean or non-Euclidean; this is a task for the physical sciences. János Bolyai
Of course it is, but the reality is that Euclidean and some non-Euclidean geometries have been shown to both be used as good models for different physical phenomena. Given that these basic axioms do seem to fit reality in some specific realms, mathematical reasoning alone
can lead to great insights. I don't care if the entire universe
is non-Euclidean, I care if a model based on non-Euclidean geometry produces good predictions about some specific phenomenon.
Quote
so we can conclude that all math has some application o the real world or its useless.
Well, it could be useless for now, and I don't put any stock in the alleged beauty of pure mathematics, but we can't tell if it will be useless forever. Oftentimes, it hasn't turned out this way (see Hardy, number theory, and the other things we've discussed). I don't think it's so hard to understand why -- it will necessarily be at least tangentially related to useful areas of mathematics, and if it leads to linkages between these areas (as it often does), there's a high propensity for that sort of thing to lead to something useful.
We have to remember that, unlike sciences, the math doesn't care what it's describing -- sometimes we find the same math is good for very unrelated phenomena (e.g. compound interest and radioactive decay behave almost identically from a mathematical standpoint as I mentioned above).