Open questions about irrational numbers

Is π+e irrational? Is sqrt(2)+sqrt(3)? One of the open questions (they don't know either way) dealing with irrational numbers is: is the sum of of two irrational numbers irrational? To address this, let's think about the crucial property of irrationals: the...

Space, time, and Lebesgue

“The more we know, the more we realize exactly how much we don't.” “It's a good beginning.. At least you're asking the right questions.” What do space, time, and Lebesgue have to do with each other? Maybe nothing.. Maybe everything.. At the moment, I feel I'm on the...