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1d

comment 
K theory long exact sequence
Thanks! Is there a standard reference for colimitcompatibility of K theory? 
1d

accepted  K theory long exact sequence 
2d

asked  K theory long exact sequence 
Jul
28 
comment 
Transcendental distance sets
The same sort of argument can be used if you're avoiding any countable collection of algebraic relations. 
Jul
28 
comment 
Transcendental distance sets
You can use Zorn's lemma and measure theory. Suppose $S$ is a maximal subset of $\mathbb{R}^n$ with no algebraic volumes  one exists by Zorn's lemma. Let $D$ be the set of all points $z$ of $\mathbb{R}^n$ such that $z$ forms a simplex of algebraic volume together with some $n$ points of $S$. Since the set of $n$tuples of points of $S$ is countable, and the set of algebraic numbers is countable, you see that $D$ is a union of a countable collection of hyperplanes, thus has measure zero. This means that there is a point in the complement to $D\cup S$, so $S$ is not maximal  contradiction! 
Jun
26 
awarded  Yearling 
May
10 
comment 
When is the Homscheme connected?
Whether or not you assume commutativity, you won't in general get connectivity. Take for example maps from the n'th neighborhood of $0$ in $\mathbb{A}^1$ into the n'th neighborhood of $0$ in $Spec(k[x,y]/(xy)$. These mapping spaces are in general at least as complicated as mapping spaces of fixed degree between projective varieties: if $A$ is functions on a neighborhood of the affine cone of a projective variety $X$ and $B$ is functions in a neighborhood of 0 in a veronese twisted affine cone of $Y$ then $Map(B,A)$ goes to $Map(X,Y)$ surjectively by taking blowups of tangent cones. 
May
10 
answered  Fundamental group of the complement homogeneous variety in $\mathbb{C}P^{n1}$ 
Apr
27 
answered  Is there a nonzero sheaf with all cohomologies vanish? 
Apr
27 
asked  Twisting stable maps to C* equivariant space by a line bundle 
Apr
5 
answered  On a theorem of Kazhdan 
Mar
25 
comment 
On a theorem of Kazhdan
Ah sorry, thought you were twisting by a character of the Levi (which would not affect the dimension... your current question makes a lot more sense). 
Mar
24 
revised 
On a theorem of Kazhdan
minor correction 
Mar
24 
awarded  Informed 
Mar
24 
revised 
On a theorem of Kazhdan
minor edit 
Mar
24 
answered  On a theorem of Kazhdan 
Mar
18 
awarded  Popular Question 
Feb
11 
awarded  SelfLearner 
Jan
12 
revised 
Twisting of the power functor
minor edit: added the word "perfect" in a couple places 
Jan
12 
comment 
Twisting of the power functor
Hi David, I mean the category of perfect modules over $T(k)$, which I think it's enough to consider as a DG algebra over $k$. (Correct me if this doesn't make sense). 