New posts in Hilbert Spaces

Show that $l^2$ is a Hilbert space

Prove that orthogonal projections in a Hilbert space satisfy $pq=0$ iff $p+q\le I$

What do mathematicians mean by "equipped"?

A operator is unitary if and only if it is a surjective isometry

Double orthogonal complement is equal to topological closure

Prove that this integral operator is compact

Difference between an isometric operator and a unitary operator on a Hilbert space

Spectrum of adjoint bounded linear operator on hilbert space

Physical interpretation of $L_1$ and $L_2$ norms

Optimization problem using Reproducing Kernel Hilbert Spaces