Alphabeta Math

Compact Self Adjoint Hilbert Schmidt and Trace Class Operators

About this page
Pipeline-generated
How statement and proof provenance work

The first chip identifies the source of the statement or construction; the second identifies the source of its local proof or verification.

  • Literature-sourced: the exact statement appears in a cited source; only wording and notation differ.
  • AI-adapted: a semantically identical restatement of literature-sourced material, modulo indexing, notation, and boundary cases adopted by the library.
  • AI-generated: a genuinely novel statement formulated by AI, with no source for the claim itself.

These labels describe origin, not correctness: citations and verification chips remain separate evidence.

1 · Prerequisites
Abstract Algebra
Combinatorics
Coxeter Groups
Functional Analysis
Linear Algebra
Number Theory
Real Analysis
Set Theory
Topology
2 · Logical flowchart

3 · Items

Lemma

Norm of a self adjoint operator from its quadratic form

Lemma

Norm point of a compact self adjoint operator is an eigenvalue up to sign

Lemma

Eigenspaces of a self adjoint operator are orthogonal

Lemma

Orthogonal complement of an eigenspace is invariant

Theorem

Spectral theorem for compact self adjoint operators

Corollary

Orthonormal eigenbasis for a compact self adjoint operator

Lemma

Positive square root of a compact positive operator

Definition

Absolute value and singular values of a compact operator

Theorem

Singular value decomposition for compact operators

Lemma

Singular values equal approximation numbers

Corollary

Compact operator iff approximation numbers tend to zero

Corollary

Finite rank operators are norm dense in compact Hilbert space operators

Theorem

Hilbert Schmidt operators form a two sided ideal

Definition

Trace class operator

Theorem

Trace class iff product of two Hilbert Schmidt operators

Lemma

Nuclear series characterizes trace norm

Theorem

Trace class is a two sided Banach operator ideal

Definition

Trace of a trace class operator

Theorem

Trace is absolutely convergent and basis independent

Theorem

Cyclicity of the trace

Theorem

Trace of a positive operator is the sum of its eigenvalues

Sources