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diracdeltafunk
  • Member for 12 years, 8 months
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33 votes
1 answer
2k views

Applications of the $\frac{5}{8}$ Theorem

20 votes
1 answer
914 views

Is this group free abelian?

12 votes
1 answer
357 views

Non-isomorphic locally ringed spaces which represent isomorphic functors $\mathsf{CommRing} \to \mathsf{Set}$.

10 votes
2 answers
2k views

Why is $\left(e^{2\pi i}\right)^i \neq e^{-2 \pi}$?

5 votes
0 answers
111 views

Endofunctors of $\textsf{FinVec}$ which are not $C^n$ [duplicate]

5 votes
2 answers
179 views

Which algebraic real numbers are eigenvalues of a finite graph?

3 votes
1 answer
343 views

Computing an explicit 2-cocycle

2 votes
1 answer
509 views

Find volume of a revolved solid by integrating wedges.

2 votes
2 answers
264 views

Approximating $\pi$ in Binary

2 votes
1 answer
128 views

Are the tangent lines to a helix disjoint?

2 votes
0 answers
86 views

Which finite groups $G$ do not embed in any symmetric group $S_n$ with $n < \lvert G \rvert$? [duplicate]

2 votes
1 answer
84 views

Elementary proof that $\mathbb{E}[1/X] \geq 1/\mathbb{E}[X]$ for finitely supported positive random variables.

1 vote
1 answer
153 views

Checking that the obvious map $SO(n, \mathbb{R}) \times \mathbb{R}^{n(n+1)/2 - 1} \to SL(n, \mathbb{R})$ is a diffeomorphism.

1 vote
1 answer
65 views

Is there always an $R$-algebra with nontrivial Picard group?

1 vote
0 answers
40 views

Can Hall's Marriage Theorem be reduced to the $d$-regular case?

1 vote
0 answers
176 views

Initial topology for "integration map"

1 vote
2 answers
102 views

Why does the derivative with respect to x of the integral from a to x of f(t) with respect to t equal f(x)?

0 votes
1 answer
51 views

Are conjugacy classes of compact groups Borel?