New posts in hilbert-spaces

a representation condition of Hilbert space

functional-analysis hilbert-spaces

$\sin$ and $\cos$ are the basis of what space?

linear-algebra functional-analysis fourier-analysis hilbert-spaces

Tensor product of operators

functional-analysis hilbert-spaces tensor-products

Normal Operators: Transform

functional-analysis operator-theory hilbert-spaces

Example of a self-adjoint bounded operator on a Hilbert space with empty point spectrum

functional-analysis operator-theory hilbert-spaces spectral-theory

Spectral Measures: Square Root

functional-analysis operator-theory hilbert-spaces

Hilbert cube is compact

real-analysis hilbert-spaces compactness lp-spaces

Is it mathematically problematic to consider the complex space of real(!)-valued functions?

functional-analysis complex-numbers soft-question hilbert-spaces

How to prove Halmos’s Inequality

functional-analysis inequality hilbert-spaces operator-theory banach-algebras

Show that the trace class operators on a Hilbert space form an ideal

functional-analysis hilbert-spaces ideals trace

Hilbert Space is reflexive

functional-analysis banach-spaces hilbert-spaces

If the image of an orthonormal basis is bounded, is the linear operator also bounded?

functional-analysis operator-theory hilbert-spaces

Characterisation of norm convergence

functional-analysis banach-spaces hilbert-spaces normed-spaces weak-convergence

Question about SOT and compact operators

functional-analysis reference-request hilbert-spaces

Proving an inequality with Cauchy-Schwarz

linear-algebra inequality hilbert-spaces quadratic-forms cauchy-schwarz-inequality

Functional weakly lower-semicontinuous [duplicate]

functional-analysis hilbert-spaces weak-convergence

Does $S^\bot+T^\bot = (S\cap T)^\bot$ hold in infinite-dimensional spaces?

linear-algebra hilbert-spaces examples-counterexamples inner-products

Nested sequence of sets in Hilbert space [duplicate]

functional-analysis hilbert-spaces

A problem about the Hilbert subspace $K = \{ f \in \text{L}^2(\mathbb{R}) \quad | \quad \text{for every $n \in \mathbb{Z} : \int_{[n,n+1]} f = 0$} \}$

real-analysis hilbert-spaces lebesgue-integral

Can Hilbert spaces be defined over fields other than $\mathbb R$ and $\mathbb C$?

linear-algebra field-theory hilbert-spaces inner-products complete-spaces