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Israel

http://provemeright.wordpress.com/

I am a Math student (and always will be). I'm currently working on homogeneous dynamics and their connections with number theory, though I'm interested in many other areas of mathematics.

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66
Two metrics induce the same topology, but one is complete and the other isn't
math.stackexchange.com

45
Idempotents in a local ring
math.stackexchange.com

28
How to understand compactness?
math.stackexchange.com

27
Irreducibility of $f(x)=x^4+3x^3-9x^2+7x+27$
math.stackexchange.com

16
Is addition continuous?
math.stackexchange.com

15
$\frac{\prod \mathbb{Z_p}}{\bigoplus \mathbb{Z_p}}$ is a divisible abelian group
math.stackexchange.com

15
All homomorphisms from the ring $\mathbb Z \times \mathbb Z \to \mathbb Z$
math.stackexchange.com

14
Combinatorial Proof of $\binom{\binom{n}{2}}{2} = 3 \binom{n}{3}+ 3 \binom{n}{4}$ for $n \geq 4$
math.stackexchange.com

12
Ahlfors's proof of analytic functions reducing to a constant
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12
Proof - Square Matrix has maximal rank if and only if it is invertible
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12
Regular but not normal space
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11
Why do elementary matrix operations not affect the row space of a given matrix?
math.stackexchange.com

10
Show that there's a bijective $f: \mathbb{N} \to \mathbb{N}$ such that $\sum_{n=1}^{\infty} (-1)^{f(n)}\ln\frac{f(n)+1}{f(n)}=\ln 2010$
math.stackexchange.com

10
Do all infinite subsets of $\mathbb N$ have a bijective function to $\mathbb N$?
math.stackexchange.com

9
If a matrix is invertible, is its multiplication commutative?
math.stackexchange.com

9
Why is the tensor product important when we already have direct and semidirect products?
math.stackexchange.com

9
Two disjoint convex closed sets that cannot be separated by a closed hyperplane?
math.stackexchange.com

8
Finite field extension with no non-trivial subextension
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7
Ideals of subrings of $M_2(\mathbb{Q})$
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7
$(-1)\otimes (-1) \cong I$
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7
$f(1-f(x))=f(x)$
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7
A simple module versus a simple ring
math.stackexchange.com

7
Identity involving Euler's totient function: $\sum \limits_{k=1}^n \left\lfloor \frac{n}{k} \right\rfloor \varphi(k) = \frac{n(n+1)}{2}$
math.stackexchange.com

7
If $\int_0^x f \ dm$ is zero everywhere then $f$ is zero almost everywhere
math.stackexchange.com

7
a nonmeasurable set $E$ of finite measure and a $G_{\delta}$ set $G$ that contains $E$
math.stackexchange.com

6
Boundedness of Continuous Bilinear Operators
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6
Extension and restriction of scalars and their relation to the identity functor
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6
A clique in a tree decomposition is contained in a bag
math.stackexchange.com

6
There does not exist group $G$ such that ${\rm Aut}(G)\cong \mathbb{Z}_n$ (for odd $n$)
math.stackexchange.com

6
The fractional part of $n\log(n)$
math.stackexchange.com

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