Is this operator compact and how do I prove it?
74147
Compactness of  Multiplication Operator on $L^2$
11558
How to show that the limit of compact operators in the operator norm topology is compact
47903
How to prove every closed interval in R is compact?
11159
Problem about a compact operator $T:l^p\rightarrow l^p$
2439
If a linear operator has an adjoint operator, it is bounded
55067
Norm of self-adjoint operator
104097
An idempotent operator is compact if and only if it is of finite rank
44738
Compact operators on an infinite dimensional Banach space cannot be surjective
158547
Question about SOT and compact operators
87897
Bounded operators on separable Hilbert spaces
95481
The set of self-adjoint operators over a Hilbert space doesn't form a lattice
66409
Show that the linear operator $(Tf)(x)=\frac{1}{\pi} \int_0^{\infty} \frac{f(y)}{(x+y)} dy$ satisfies $\|T\|\leq 1$.
156727
A step in the proof of Characterization of $W^{1,\infty}$
57609
Hahn-Banach proof by extension of basis
138784
Is the differentiation operator an open mapping?
155317
Norm of adjoint operator in Hilbert space
72240
Prove that if a linear operator is continuous, then it is bounded.