glS's user avatar
glS's user avatar
glS's user avatar
glS
  • Member for 9 years, 7 months
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  • Europe
16 votes

How unique are $U$ and $V$ in the singular value decomposition $A=UDV^\dagger$?

14 votes

How to find a basis for the intersection of two vector spaces in $\mathbb{R}^n$?

10 votes

What are good examples of polar sets in $\mathbb R^2$?

9 votes
Accepted

What is the metric on the $n$-sphere in stereographic projection coordinates?

8 votes

What is the difference between isometric and unitary operators on a Hilbert space?

8 votes

What is a basis for the space of $n\times n$ Hermitian matrices?

5 votes

How do I find the series expansion of the meromorphic function $\frac{1}{e^z+1}$?

5 votes

Prove that $f(x) = x^3 -x $ is surjective

5 votes

Why does raising group elements to the power of the order of the group yield the identity?

4 votes

$ \int_{-\infty}^{\infty} x^4 e^{-ax^2} dx$

4 votes

Prove that the product of two positive linear operators is positive if and only if they commute.

4 votes

What does it mean to be "affinely independent", and why is it important to learn?

4 votes

Why do $SO(n,\mathbb{R})$ and $O(n,\mathbb{R})$ have the same Lie algebra?

3 votes

Proof of Segner's lemma for the number of sign alternations in polynomials

3 votes

Prove that the eigenvalues of skew-Hermitian matrices are purely imaginary

3 votes

How to prove that eigenvectors from different eigenvalues are linearly independent

3 votes

How can I prove that $\sum_{n=1}^\infty \frac{1}{n(n+1)} = 1$?

3 votes

Orthogonal projections with $\sum P_i =I$, proving that $i\ne j \Rightarrow P_{j}P_{i}=0$

2 votes

How does the SVD solve the least squares problem?

2 votes
Accepted

Prove operator has eigenvalue with fundamental theorem of algebra

2 votes

Is every linear projection normal?

2 votes

Prove that the Schmidt number of a state is equal to the rank of the reduced density matrix

2 votes

derivative of $f(x)=(4x^2+9)^7(7x^2+3)^{12}$

2 votes
Accepted

Show that for any invertible $A$, if $P\equiv\sqrt{A^\dagger A}$ then $U\equiv A P^{-1}$ is unitary

2 votes

How do "Eigenbases" and "orthonormal bases" relate?

2 votes

Why are finite representations of finite groups always diagonalisable?

2 votes

How does the definition of tangent space in terms of equivalence classes of curves relate with the intuitive notion of tangent vectors?

2 votes
Accepted

How do I recover a convex region from the set of its tangent planes?

2 votes
Accepted

What does $A+B=I$ imply for positive matrices $A,B$?

2 votes
Accepted

Prove that for every $p\in N$ we have $(dF^{-1})_{F(p)}=(dF)^{-1}_p$, with $F:N\to M$ a diffeomorphism