13 Answers votes newest views recent 0Representation of double cover of $U(n)$ on eigenspaces of harmonic oscillator 2Covariant derivative 0when can we lift an action of Lie algebra? 2Lie group operation and tangent vectors 1Defining the inverse of the Bott map 7Conformal-symplectic geometry ? 1Why is the x->x^1/3 atlas on R diffeomorphic with the x->x atlas on R? 5Lie group actions and f-relatedness 6Demystifying complex numbers 1Functional Analysis and its relation to mechanics 17What are the most elegant proofs that you have learned from MO? 0Representations of Pin vs. Representations of Clifford 6Is there any geometry where the triangle inquality fails?