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rmdmc89's user avatar
rmdmc89's user avatar
rmdmc89
  • Member for 9 years, 6 months
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33 votes
Accepted

Understanding the orientable double cover

14 votes

How can three vectors be orthogonal to each other?

11 votes

What's the difference between time-dependent flow (isotopy) and time-independent flow?

11 votes

Orientability of a product of smooth manifolds implies orientability of each factor

7 votes
Accepted

Asymptotic formula for $\sum_{n\leq x}\sigma(n)$ knowing $\sum_{n\leq x}\frac{\sigma(n)}{n}$

6 votes

Why the emphasis on Projective Space in Algebraic Geometry?

6 votes
Accepted

Product rule for matrix-valued functions and Differentiability of matrix multiplication

5 votes

Fiber Product is an embedded submanifold

5 votes

Prove the sphere is orientable

4 votes

Sum of conditional probabilities equals 1?

4 votes
Accepted

There exist only finitely many λ ∈ C such that det(λA + (1 − λ)B) = 0

4 votes
Accepted

Krull dimension of $\mathbb{R}[x_1, \ldots, x_n]/(F)$?

4 votes

Residue field at the generic point is equal to the fraction field of the section

3 votes

Every irreducible closed has a generic point

3 votes
Accepted

Conormal bundle and lagrangian submanifold

3 votes
Accepted

$f:N\to M$ with degree $\neq 0\Rightarrow f^*:H^k(M)\to H^k(N)$ injective for all $k$

3 votes

Existence of a smooth frame for a vector bundle

3 votes

Given a basis of $T_pM (e_i)$. Extend this base to a local orthonormal frame $(E_i)$ with $\nabla E_i (p) = 0 $

2 votes

Prove that the Lie derivative of a vector field equals the Lie bracket: $\frac{d}{dt} ((\phi_{-t})_* Y)|_{t=0} = [X,Y]$

2 votes

On the generators of the Modular Group

2 votes
Accepted

Open hemisphere is connected

2 votes

If $f$ is a scalar field on $\mathbb{R}^2$, how do I interpret the quantity $x\frac{\partial f}{\partial y} - y\frac{\partial f}{\partial x}$?

1 vote

How did Euler and Bernoulli prove this limit?

1 vote
Accepted

$F/K$ with a rational place $\Rightarrow F=K(x,y)$ with $[F:K(x)]=[F:K(y)]=2g+1$

1 vote

If every intermediate ring of a field extension is a field, then the extension is algebraic

1 vote
Accepted

Proof Verification: A differentiable aplication $\psi : M\to N$ is differentiable if and only if: $\psi^{*}f\in C^{\infty}(M)$

1 vote

What is the name of this curve?

1 vote
Accepted

Neutral element in $\hom_C(A, B)$

1 vote

$\mathbb{Z}[\alpha]$ is f.g. if $\alpha$ is an algebraic integer.

1 vote

Does partition of unity implies second countable?