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Simon Rose

Canada

http://charlesflorian.wordpress.com/

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Top Questions
49 votes

What are the benefits of viewing a sheaf from the “espace étalé” perspective?

ag.algebraic-geometry sheaf-theory ct.category-theory asked May 7 '12 at 21:01
mathoverflow.net

45 votes

What is the purpose of the flat/fppf/fpqc topologies?

ag.algebraic-geometry grothendieck-topology asked Jan 29 '15 at 10:33
mathoverflow.net

32 votes

Is there a nice explanation for this curious fact about cyclic subgroups?

nt.number-theory gr.group-theory finite-groups abelian-groups p-groups asked Jun 3 '16 at 9:43
mathoverflow.net

19 votes

How many ways can I factor a matrix (over $\mathbb{Z}$)?

matrices algebraic-groups arithmetic-groups asked Mar 29 '16 at 14:01
mathoverflow.net

16 votes

Can one determine the dimension of a manifold given its 1-skeleton?

gn.general-topology manifolds simplicial-complexes triangulations asked Jan 6 '19 at 19:31
mathoverflow.net

15 votes

How do modular forms of half-integral weight relate to the (quasi-modular) Eisenstein series?

modular-forms theta-function eisenstein-series quasimodular-forms half-integral-weight asked Sep 8 '10 at 18:28
mathoverflow.net

14 votes

How many sporadic simple groups are there, really?

gr.group-theory finite-groups sporadic-groups asked Dec 10 '13 at 18:02
mathoverflow.net

14 votes

Am I missing something about this notion of Mirror Symmetry for abelian varieties?

ag.algebraic-geometry elliptic-curves abelian-varieties k3-surfaces mirror-symmetry asked Dec 1 '14 at 12:48
mathoverflow.net

13 votes

What relations exist among (quasi-) modular forms of different levels?

modular-forms nt.number-theory asked Mar 22 '11 at 22:39
mathoverflow.net

12 votes

Why isn't the orbifold cohomology of $pt/G$ equal to the cohomology of $BG$?

group-cohomology orbifolds classifying-spaces asked Mar 3 '11 at 0:02
mathoverflow.net

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Top Answers
65
Is there a domain “larger” than (i.e., a supserset of) the complex number domain?
math.stackexchange.com

36
Intuition behind normal subgroups
math.stackexchange.com

33
What's the sum of all the positive integral divisors of $540$?
math.stackexchange.com

27
Prove that the additive groups $\mathbb{Z}$ and $\mathbb{Q}$ are not isomorphic.
math.stackexchange.com

17
de Rham vs Dolbeault Cohomology
mathoverflow.net

15
Is every algebraic $K3$ surface a quartic surface?
mathoverflow.net

13
What recent discoveries have amateur mathematicians made?
mathoverflow.net

12
Elliptic curves on abelian surface
mathoverflow.net

12
Complex torus, C^n/Λ versus (C*)^n
mathoverflow.net

11
Examples of “Unusual” Classifications
mathoverflow.net

9
Identifying the generating function $ G(a,z) = \sum_{n=0}^{\infty} a^n z^{(n+1)(n+2)/2}. $
mathoverflow.net

9
Sum $\frac{1}{1\times2}+\frac{1}{1\times3}+\frac{1}{2\times5}+\frac{1}{3\times8}+\cdots$
math.stackexchange.com

8
Given a normal subgroup N⊆G, when does G contain a subgroup isomorphic to G/N?
mathoverflow.net

8
Existence of Homomorphism so that Diagram Commutes
math.stackexchange.com

8
Understanding the definition of the quotient stack $[X/G]$
mathoverflow.net

8
show that $\frac{1}{F_{1}}+\frac{2}{F_{2}}+\cdots+\frac{n}{F_{n}}<13$
math.stackexchange.com

7
Triviality of finite fiber bundles
mathoverflow.net

7
Examples in mirror symmetry that can be understood.
mathoverflow.net

7
Blackboard rendering of math fonts
mathoverflow.net

7
What is the meaning of non-Hausdorff spaces in algebraic geometry
mathoverflow.net

7
What exactly is a dimension?
math.stackexchange.com

7
101102103104105106…149150? What is the remainder when divided by 9?
math.stackexchange.com

7
Integral element in $\mathbb{Q}(\sqrt{2})$ over $\mathbb{Z}$ has form $m+n\sqrt{2}$
math.stackexchange.com

6
What is a branched Riemann surface with cuts?
mathoverflow.net

6
How do I evaluate $\int \frac{\mathrm{d}x}{e^x + 1} $?
math.stackexchange.com

6
Examples for Stone–Čech compactification
math.stackexchange.com

6
Trivial Fundamental Group Notation (1 or 0)
math.stackexchange.com

5
What is the quantity 2(handles)+crosscaps called?
mathoverflow.net

5
Reference request: Equivariant Topology
mathoverflow.net

5
$\psi$ class in $\overline{M}_{0,n}$
mathoverflow.net

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