Skip to main content
8 events
when toggle format what by license comment
Jan 6, 2013 at 12:13 comment added Ritwik Thank you. I see why the scalar curvature can not equal the $*e(TM)$.
Jan 5, 2013 at 19:11 comment added Otis Chodosh *by my first sentence, I mean an identity between scalar curvature and the Gauss-Bonnet integrand (as @unknown comments)
Jan 5, 2013 at 19:10 comment added Otis Chodosh ...giving a contradiction. You may be interested in the following MO post: mathoverflow.net/questions/30035/….
Jan 5, 2013 at 19:09 comment added Otis Chodosh @Ritwik, there is no possibility of such an identity holding. If $*e(TM)$ was some multiple of the scalar curvature $R$, this would imply that $\int R = \int *e(TM) dV = <e(TM),[M]>$, and this is a topological invariant of the (smooth structure) topology of $M$. (see en.wikipedia.org/wiki/…). However, one can show that in dimensions $\geq 3$, all manifolds admit a metric of negative scalar curvature, e.g. $S^3$. So, if the above identity held, we could evaluate $<e(TM),[M]>$ on the standard metric and this other one...
Jan 5, 2013 at 19:00 comment added John Pardon I assume that by $\ast e(TM)$ you mean the Gauss--Bonnet integrand. In dimensions at least three, it is different from the scalar curvature. So prescribing scalar curvature is a different question in dimensions at least three.
Jan 5, 2013 at 15:54 comment added Ritwik I am sorry if this is a trivial question or a well known fact, but is the Scalar curvature the same as $*e(TM)$ (maybe upto a constant factor)?
Jan 5, 2013 at 15:43 comment added Liviu Nicolaescu Check this Wikipedia page en.wikipedia.org/wiki/Prescribed_scalar_curvature_problem
Jan 5, 2013 at 15:17 history asked Ritwik CC BY-SA 3.0