22 Answers votes newest views recent 3Newton equations, second order equation and (im)possible motions 1Who first proved that the value of C/d is independent of the choice of circle? 6To what extent does trajectory determine gravity sources? 3Geometric picture of scalar curvature 1Tensor contraction and Covariant Derivative 1Quantization of a classical system (e.g. the case of a billard) 4How are mathematical objects defined from an ultrafinitist perspective? 4Mathematical “proof” of the stability of atoms? -1Even XOR Odd Infinities? 2Old books still used 5Permuting Racked Pool Balls with a Single Break 2Permission to use Online Notes 5Does Physics need non-analytic smooth functions? 4Where to publish a math textbook in Creative Commons 2Does there exist a non-trivial Ultrafinitist set theory? 0Multivariable Calculus Lecture Ideas 4Quantum mechanics basics 2Different ways of thinking about the derivative 1Singular scalar curvature 2Interpretation of Curvature and Torsion 3Do you find your students are less competent in basic algebra and arithmetic, and, if so, do you believe that this is due to overuse of calculators at an early level? 7Does Godel’s Incompletenss Theorem mean there is no solution to Hilbert’s 6th Problem?