Timeline for Properties of a subring of a 'completion' of k(X_1, X_2, ..., X_n)

8 events

when toggle format	what		by	license	comment
Jul 4, 2016 at 14:22	history	edited	Jeremy Cochoy	CC BY-SA 3.0	added 223 characters in body
Jun 30, 2016 at 22:07	comment	added	YCor		(I removed the redundant tag "commutative-rings"; for those with enough (I don't know how many) reputation points please upvote the synonym suggestion mathoverflow.net/tags/synonyms?filter=suggested&tab=newest so that commutative-rings will automatically be changed to ac.commutative-algebra)
Jun 30, 2016 at 22:05	history	edited	YCor		edited tags
Jun 30, 2016 at 19:40	history	edited	Neil Strickland	CC BY-SA 3.0	Spelling
Jun 30, 2016 at 15:17	comment	added	YCor		It's the group algebra over $k$ of the additive group of $\mathbf{R}^n$, sometimes denotes $k[\mathbf{R}^n]$, or, if you only allow nonnegative exponents, it's the semigroup algebra $k[\mathbf{R}_+^n]$ over $k$ of the additive $\mathbf{R}_+^n$, where $\mathbf{R}_+=[0,+\infty[$. As a $k$-algebra, it has no memory of the structure of the reals, $\mathbf{R}^n$ being isomorphic to $\mathbf{Q}^{(c)}$ additively ($c$ = continuum), it's isomorphic as $k$-algebra to $k[\mathbf{Q}^{(c)}]$, which is a bit ugly.
Jun 30, 2016 at 15:06	comment	added	Laurent Moret-Bailly		Can you please define this ring?
Jun 30, 2016 at 14:58	review	First posts
Jun 30, 2016 at 15:44
Jun 30, 2016 at 14:54	history	asked	Jeremy Cochoy	CC BY-SA 3.0