0
votes
1answer
104 views
blow-ups and singularities
Let $X$ be a smooth and projective variety over a field of characteristic zero. Let $Y$ be a normal variety, with finite quotient singularities (an orbifold!) and let $\pi: Y \to X …
14
votes
1answer
1k views
Two versions of “absolutely ccc”
I have recently been slogging my way through Shelah's "Large continuum, oracles". Essentially from the start there has been a question needling me which I cannot seem to answer.
…
3
votes
1answer
277 views
Trivializing principal bundles on a curve over a finite field
This is related to my question Adelic description of moduli of $G$-bundles on a curve.
Let $X$ be a smooth, projective, and geometrically connected curve over a finite field $\mat …
0
votes
0answers
9 views
Analytic dependence on the metric
It is often used implicitly that the maps which associate to metrics curvature quantities (Riemann, Ricci, scalar curvature) and Differential operators like the Laplacian are analy …
0
votes
1answer
68 views
When is an ample line bundle on an abelian variety base point free?
So, any line bundle $L$ on an abelian variety $X$ determines a type $(d_1,\ldots,d_g)$ where $d_i|d_{i+1}$. It's well known that if $d_1\geq 3$ then $L$ defines an embedding, that …
28
votes
2answers
1k views
Moving one family of commuting self-adjoint operators to another without losing commutativity on the way
This is actually not a question of mine, so I'll be short on motivation and say nothing beyond that if this were true, a few fancy harmonic analysis techniques that a colleague of …
0
votes
0answers
11 views
Varieties which become isomorphic to algebraic groups over an algebraic closure
My question is as follows:
Let $k$ be a field of characteristic zero and let $\overline{k}$ be an algebraic closure. Let $V$ be an algebraic variety over $k$ and let $\overline …
0
votes
0answers
16 views
Nondegenerate bilinear form
Could anybody please advice me, how to show that nondegenerate bilinear form with property $f(u,v)=-f(v,u)$ on vector space $V$ exists iff $dim V = 2l$?
5
votes
3answers
617 views
Why has Bourbaki ignored the theory of categories?
They had plenty of time to adopt the theory of categories. They had Eilenberg, then Cartan, then Grothendieck. Did they feel that they have established their approach already, that …
0
votes
1answer
70 views
Dual space of Bochner space: is there an easier proof to show they’re isometric?
It is known that $[L^p(0,T;H)]^* = L^q(0,T;H^*)$.
If $p=q=2$ and $H$ is a Hilbert space, is there an easier proof to show that the spaces are isometric? The proof that I know for …
0
votes
1answer
48 views
Families of Hurwitz Curves
Hurwitz's theorem on automorphisms tells us that the group of automorphisms of a nonsingular complex algebraic curve of genus at least 2 is bounded above by $84(g-1)$ where $g$ is …
0
votes
1answer
68 views
Relations between automorphisms of field of rational functions and Mobius Transfomation
Proposition: If $F$ is a field, let $F[x]$ be the ring of all polynomials whose coefficients are in $F$. The fraction field of $F[x]$, denoted $F(x)$, is defined to be the ratios $ …
1
vote
5answers
236 views
Spinoffs of analytic number theory
What are some techniques and theorems of analytic number theory that have proved useful outside of number theory?
0
votes
0answers
9 views
Any bounded covering transformation invariant cocycle cohomologous to a straight cocycle?
In Gromov's paper "volume and bounded cohomology"1982 http://scholar.google.com.hk/scholar?hl=zh-CN&q=volume+and+bounded+cohomology&btnG=&lr= .As a step for proving tha …
0
votes
0answers
45 views
What’s wrong with this arithmetic model for the change in the perception of “number” of quantum states?
Maybe one of the strange things about quantum mechanics comes from the mental dificulty of reconciling the fact that a system in a superposition of several states, when measured or …

