Daniel's user avatar
Daniel's user avatar
Daniel's user avatar
Daniel
  • Member for 9 years, 11 months
  • Last seen more than a month ago
19 votes
Accepted

Spectrum of the derivative operator

5 votes
Accepted

Alternative Proof for a Lemma in Barry Simon's "Operator Theory"

5 votes
Accepted

Definition a weakly continuous mapping

5 votes

Ways to calculate the spectrum of an operator

4 votes

Spectra of operators on different spaces

3 votes
Accepted

Is this another version of the gamma function?

3 votes

Prove or disprove: $A=A^\top \land B = B^\top \Rightarrow AB = (AB)^\top$

2 votes

Where is the error in my proof?

2 votes

Topology of test functions $\mathcal{D}(\mathbb R)$

2 votes

$G$ is an abelian group of order a product of distinct primes $\implies G$ is cyclic?

2 votes
Accepted

Interpretation of a limit inferior

1 vote

Find the Fourier Transform of $e^{i x t}$.

1 vote

prove $ \displaystyle \lim_{x \to 0} (1+x)^{\frac {1}{x} } = e $ by epsilon delta?

1 vote

application of c*algebras to PDEs

1 vote

Is kinetic energy a positive definite quadratic form?

1 vote

Inequality with limsup from baby Rudin

1 vote

If W is a subspace of V then $W^⊥$ is a subspace of $V^⊥$?

1 vote
Accepted

Orthogonality of Hermite functions

1 vote
Accepted

If $u \in H^1(0,\infty)$, does $u_x(\infty) = 0$?

1 vote
Accepted

What does $\overline B(0,1)\subseteq (\mathscr{C}([0,1],\mathbb{C}),d_\infty)$ mean?

0 votes
Accepted

Is it true that if $cl(S) = int(S) \cup \partial (S)$ and $cl(S) = S \cup \partial (S)$ then $int(S) = S$ which means $S$ is open?

0 votes

vector and curl identity

0 votes

Weak convergence and strong convergence in $L^1$.

0 votes

Square root of symmetric matrix

0 votes

Radon-Riesz & Kadec-Klee