Thomas Klimpel
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 Oct 30 asked Can the b-adic representation of rational numbers (by quote notation) be extended to non-terminating expansions? Oct 28 awarded Revival Oct 16 reviewed Approve coordinate geometry high level problems Oct 7 reviewed Approve infinitely many solutions to $\displaystyle x^n + y^n = z^{n+1}$ Oct 7 comment Are higher order logics substantially stronger than second order In a certain sense, this answer is only true if the other axioms ensure that there are infinitely many objects/elements in the universe. And if the other axioms already ensure that we have the consistency strength of bounded Zermelo set theory or ZFC set theory, then just adding higher order variables and impredicative comprehension axioms (without using higher order variables in some of the other axioms) won't increase consistency strength any further. Oct 6 revised Are higher order logics substantially stronger than second order Oh, I forgot that I wanted to say something about the last word property Oct 6 answered Are higher order logics substantially stronger than second order Oct 5 revised Is multiplication in mixed radix numeral systems complicated? edited tags Oct 4 asked Is multiplication in mixed radix numeral systems complicated? Sep 30 awarded Explainer Sep 28 comment Why are real numbers useful? Nice answer, but when you say "And the wanted this line to be with no gaps, to be a continuum," what do you mean by "no gaps"? The rational numbers have no gaps either, in a certain sense. In another sense, the real numbers have gaps too, for example if you look at them as a subset of the surreal numbers. I think instead of the unclear "no gaps", what they really wanted was "completeness" (not necessarily limited to the order) and the Archimedean property: $\forall x\in {\mathbb R} \quad \exists n\in {\mathbb N} \quad x < n$. Aug 18 answered How much maths can we do in NF(U)? Aug 17 revised Why learn to solve differential equations when computers can do it? fixed links Aug 16 answered Why learn to solve differential equations when computers can do it? Aug 15 revised Which natural number predicates can be defined in Robinson arithmetic? edited body Aug 15 answered Can Goodstein's theorem be expressed as an axiom or axiom scheme in PA? Aug 15 answered Which natural number predicates can be defined in Robinson arithmetic? Jul 22 comment Why are box topology and product topology different on infinite products of topological spaces? @MathsLover The set theoretical topological spaces where defined by Felix Hausdorff in his book "Grundzüge der Mengenlehre", which appeared in 1914. In 1912, Jan Brouwer had started intuitionism, but Felix Hausdorff's work is not really based on it. The linked publication page of Dirk van Dalen is a good source for the connections between formal intuitionistic logic and topological spaces. If the links in that page don't work in your browser, copy the desired "link address" and replace "papers.html" in the current addresss by "articles/..." from the copied "link address". Jul 20 answered Why are box topology and product topology different on infinite products of topological spaces? Jul 18 comment Can a biased physical random source be post-processed to control the bias? @Did Thanks, now I see where I made a mistake in the description of the method. Should be fixed now. This also answers part of my initial confusion, i.e. why I asked this sort of questions in the first place.