Compact Self Adjoint Hilbert Schmidt and Trace Class Operators — Examples
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1 · Prerequisites
Abstract Algebra
- Algebraic Closure, Embeddings, and Separability
- Algebraic Extensions, Extension Degree, and Finite Fields
- Binary Operations, Monoids, Groups and Subgroups
- Composition Series, the Jordan–Hölder Theorem and Solvable Groups
- Cosets, Index and Lagrange's Theorem
- Cyclic Groups and Direct Products
- Divisibility, Euclidean Domains, Principal Ideal Domains and Unique Factorisation
- Group Actions, Orbits, Stabilisers and Cayley's Theorem
- Group Homomorphisms and the Isomorphism Theorems
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- Rings, Subrings, Integral Domains and Fields
- Simple Field Extensions and the Construction of the Complex Numbers
- Splitting Fields
- Sylow's Theorems, p-Groups and Nilpotent Groups
- The Fundamental Theorem of Algebra
- The Fundamental Theorem of Finite Abelian Groups
- The Galois Correspondence
Functional Analysis
- Banach Valued Integration and the Radon Nikodym Property
- Bounded Linear Operators and Quotient Spaces
- Compact Operators and Riesz Schauder Theory
- Compact Self Adjoint Hilbert Schmidt and Trace Class Operators
- Complex Norms and Realification
- Complex Subspace Realification
- Dual Spaces Adjoint Operators and Annihilators
- Finite Dimensional Normed Spaces and Riesz Lemma
- Geometric Hahn Banach and Convex Separation
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- Normed and Banach Spaces
- Norming and Separation under Hahn–Banach
- Orthonormal Bases, Parseval and Fourier Series
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- The Analytic Hahn Banach Theorem
- The Baire Principles of Functional Analysis
Linear Algebra
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- Linear Independence, Bases and Dimension
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- Triangularisation, Generalised Eigenspaces and Jordan Canonical Form
- Vector Spaces, Linear Subspaces, Span and Direct Sums
Measure Theory
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- The Lᵖ Spaces Holder Minkowski and Riesz Fischer
Number Theory
Real Analysis
- Absolute and Conditional Convergence; Rearrangement; Products
- Approximation and Compactness in C(K)
- Areas of Elementary Plane Figures
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- Sequences and Limits
- Sequences and Series of Functions; Uniform Convergence
- Series: Convergence and the Nonnegative Tests
- Suprema and Infima
- The Cantor Set, Baire Category, and Measure Zero in ℝ
- The Complex Exponential and Euler's Formula
- The Derivative and the Mean Value Theorems
- The Exponential Function
- The Fundamental Theorems of Calculus
- The Logarithm and General Powers
- The Riemann Integral in Rᵐ and Jordan Content
- The Riemann Integral: Definition and Integrability
- The Total Derivative in ℝᵐ → ℝⁿ
- Topology of ℝ
Set Theory
Topology
- Compactness
- Compactness in Metric Spaces
- Completeness, Completion, and Uniform Continuity
- Convergence: Nets and Filters
- Countability Axioms and Cardinal Functions
- Metric Spaces
- Separation Axioms: the Hierarchy
- Subspaces, Products, and Quotients
- The Topology of Euclidean Space
- Topological Spaces and Continuity
2 · Logical flowchart
3 · Items
Example
Diagonal Schatten class criteria on ell two
Example
Volterra operator is Hilbert Schmidt and quasinilpotent
Example
Adjoint, norm and trace of an operator of rank at most one
Example
Integral operator trace under a valid diagonal hypothesis
Counterexample
Compact does not imply Hilbert Schmidt
Counterexample
Hilbert Schmidt does not imply trace class
Counterexample
The unilateral shift obstructs a cyclic linear trace extension
Remark
Schatten p classes
Sources
- Gerald Teschl, Topics in Real and Functional Analysis, version November 17, 2017 — §3.5–§3.6, diagonal operators and Schatten classes
- Gerald Teschl, Topics in Real and Functional Analysis, version November 17, 2017 — §3.1 and §3.6, the Volterra operator
- Anthony W. Knapp, Advanced Real Analysis — Chapter II, §5, rank-one operators
- Gerald Teschl, Topics in Real and Functional Analysis, version November 17, 2017 — §10.5, Lemma 10.26 and Theorem 10.27 (Mercer, printed pp. 304–306)
- Gerald Teschl, Topics in Real and Functional Analysis, version November 17, 2017 — §3.6, compact but not Hilbert–Schmidt diagonal operators
- Gerald Teschl, Topics in Real and Functional Analysis, version November 17, 2017 — §3.6, Hilbert–Schmidt but not trace-class diagonal operators
- Gerald Teschl, Topics in Real and Functional Analysis, version November 17, 2017 — §3.6, the shift and the failure of cyclicity without trace class
- Gerald Teschl, Topics in Real and Functional Analysis, version November 17, 2017 — §3.6, Schatten classes
- Anthony W. Knapp, Advanced Real Analysis — Chapter II, §5