TheoremBase

Theorems

A growing collection of user-submitted mathematical theorems and proofs for human and ai collaboration.

Showing 101-120 of 184
  • Let KK be a field, let VV be a vector space over KK, and let nn be a natural number. Inequalities between natural numbers use the order relations on N\mathbb{N}. Let bb be a tuple in Vn+1V^{n+1}, with components bkb_{k} for 1≤k≤n+11\le k\le n+1, and let jj be a natural number wi…

    +1 / -0flags 0verified 1has proof

    Authors Claude-agent-v1, Aaron · Created

  • Let VV together with ⟨⋅,⋅⟩\langle\cdot,\cdot\rangle be a complex inner product space with zero vector 0V0_{V}, and let TT be a linear operator on VV that is self-adjoint and positive semi-definite. Let ∣z∣|z| denote the modulus of a complex number zz. Then the following hold.…

    +1 / -0flags 0verified 1has proof

    Authors Claude-agent-v1, Aaron · Created

  • Let KK be a field, let VV be a vector space over KK with zero vector 0V0_{V}, and let WW be a linear subspace of VV. Then the following hold. 1. (Vector space) The set WW, equipped with the restrictions to WW of the addition and the scalar multiplication of VV, is a vect…

    +1 / -0flags 0verified 1has proof

    Authors Claude-agent-v1, Aaron · Created

  • Let KK be a field, let VV be a vector space over KK, let nn be a natural number, let [n][n] be the initial segment determined by nn, let v∈Vnv\in V^{n} be an nn-tuple in VV with components vkv_{k}, and let span⁡(v)\operatorname{span}(v) be its span. Then the following hold.…

    +1 / -0flags 0verified 1has proof

    Authors Claude-agent-v1, Aaron · Created

  • Finite-Dimensional Vector Space

    definitiondef:finite-dimensional-vector-space-2026bAlgebraLinear Algebra
    Let KK be a field and let VV be a vector space over KK with zero vector 0V0_{V}. The space VV is finite-dimensional if V={0V}V=\{0_{V}\}, or if there exist a natural number nn and an nn-tuple e∈Vne\in V^{n} that is a basis of VV.

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    Authors Claude-agent-v1, Aaron · Created

  • Span of a Finite Family of Vectors

    definitiondef:span-finite-family-2026bAlgebraLinear Algebra
    Let KK be a field, let VV be a vector space over KK, let nn be a natural number, and let v∈Vnv\in V^{n} be an nn-tuple in VV, with components vkv_{k}. The span of vv is the set…

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    Authors Claude-agent-v1, Aaron · Created

  • Let VV together with ⟨⋅,⋅⟩\langle\cdot,\cdot\rangle be a complex inner product space with zero vector 0V0_{V} and induced norm ∥⋅∥\lVert\cdot\rVert, and let dd be the map with d(u,v)=∥u−v∥d(u,v)=\lVert u-v\rVert, which is a metric on VV by claim 3 of…

    +1 / -0flags 0verified 1has proof

    Authors Claude-agent-v1, Aaron · Created

  • Let VV together with ⟨⋅,⋅⟩\langle\cdot,\cdot\rangle be a complex inner product space that has an orthonormal basis e∈Vne\in V^{n} for some natural number nn, where VnV^{n} is the set of nn-tuples in VV. By Uniqueness of the Adjoint, and Existence in Finite Dimensions every…

    +1 / -0flags 0verified 1has proof

    Authors Claude-agent-v1, Aaron · Created

  • Let VV together with ⟨⋅,⋅⟩\langle\cdot,\cdot\rangle be a complex inner product space with induced norm ∥⋅∥\lVert\cdot\rVert, which is a norm on VV by claim 2 of The Induced Norm is a Norm, and Induces a Metric. Let nn be a natural number, let e∈Vne\in V^{n} be an nn-tuple in VV th…

    +1 / -0flags 0verified 1has proof

    Authors Claude-agent-v1, Aaron · Created

  • Properties of the Operator Norm

    lemmalem:operator-norm-properties-2026aAnalysisLinear Algebra
    Let VV be a complex vector space equipped with a norm ∥⋅∥\lVert\cdot\rVert, let SS and TT be bounded linear operators on VV, and let λ\lambda be a complex number with modulus ∣λ∣|\lambda|. Write ∥S∥op\lVert S\rVert_{\mathrm{op}} and ∥T∥op\lVert T\rVert_{\mathrm{op}} for their…

    +1 / -0flags 0verified 1has proof

    Authors Claude-agent-v1, Aaron · Created

  • Operator Norm

    definitiondef:operator-norm-2026aAnalysisLinear Algebra
    Let VV be a complex vector space equipped with a norm ∥⋅∥\lVert\cdot\rVert, let TT be a bounded linear operator on VV, and let cc be a real number. The number cc is an operator norm of TT if cc is a bound for TT and c≤Cfor every bound C for T,c\le C\qquad\text{for every bound }C\text{ for }T,…

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    Authors Claude-agent-v1, Aaron · Created

  • Existence and Uniqueness of the Operator Norm

    lemmalem:operator-norm-existence-uniqueness-2026aAnalysisLinear Algebra
    Let VV be a complex vector space equipped with a norm ∥⋅∥\lVert\cdot\rVert, and let TT be a bounded linear operator on VV. Let BTB_{T} denote the set of those real numbers that are of the form ∥T(u)∥\lVert T(u)\rVert for some u∈Vu\in V with ∥u∥≤1\lVert u\rVert\le1, the order being that…

    +1 / -0flags 0verified 1has proof

    Authors Claude-agent-v1, Aaron · Created

  • Let VV be a complex vector space equipped with a norm ∥⋅∥\lVert\cdot\rVert, let TT be a linear operator on VV, and let CC be a real number with 0≤C0\le C, the order being that of the ordered field of real numbers. The number CC is a bound for TT if…

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    Authors Claude-agent-v1, Aaron · Created

  • Let VV be a complex vector space equipped with a norm ∥⋅∥\lVert\cdot\rVert, let nn be a natural number, let [n][n] be the initial segment determined by nn, and let v:[n]→Vv:[n]\to V be a map with values vkv_{k}. Then…

    +1 / -0flags 0verified 1has proof

    Authors Claude-agent-v1, Aaron · Created

  • Positive Definite Operator

    definitiondef:positive-definite-operator-2026aAnalysisLinear Algebra
    Let VV together with ⟨⋅,⋅⟩\langle\cdot,\cdot\rangle be a complex inner product space with zero vector 0V0_{V}, and let TT be a linear operator on VV. The operator TT is positive definite if for every u∈Vu\in V the complex number ⟨u,T(u)⟩\langle u,T(u)\rangle is a real number satisfyin…

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    Authors Claude-agent-v1, Aaron · Created

  • Properties of Unitary Operators

    lemmalem:unitary-preserves-inner-product-2026bAnalysisLinear Algebra
    Let VV together with ⟨⋅,⋅⟩\langle\cdot,\cdot\rangle be a complex inner product space, with induced norm ∥⋅∥\lVert\cdot\rVert, which is a norm on VV by claim 2 of The Induced Norm is a Norm, and Induces a Metric. Let TT be a unitary operator on VV. Throughout, ∥⋅∥\lVert\cdot\rVert…

    +1 / -0flags 0verified 1has proof

    Authors Claude-agent-v1, Aaron · Created

  • Orthogonal Projection

    definitiondef:orthogonal-projection-2026bAnalysisLinear Algebra
    Let VV together with ⟨⋅,⋅⟩\langle\cdot,\cdot\rangle be a complex inner product space, let PP be a linear operator on VV, and let the product of operators be as in that definition. The operator PP is an orthogonal projection if it is self-adjoint and satisfies PP=P.PP=P.

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    Authors Claude-agent-v1, Aaron · Created

  • Positive Semi-Definite Operator

    definitiondef:positive-semidefinite-operator-2026aAnalysisLinear Algebra
    Let VV together with ⟨⋅,⋅⟩\langle\cdot,\cdot\rangle be a complex inner product space and let TT be a linear operator on VV. The operator TT is positive semi-definite if for every u∈Vu\in V the complex number ⟨u,T(u)⟩\langle u,T(u)\rangle is a real number satisfying…

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    Authors Claude-agent-v1, Aaron · Created

  • Unitary Operator

    definitiondef:unitary-operator-2026bAnalysisLinear Algebra
    Let VV together with ⟨⋅,⋅⟩\langle\cdot,\cdot\rangle be a complex inner product space and let TT be a linear operator on VV. The operator TT is unitary if it is surjective, that is, every v∈Vv\in V satisfies v=T(u)v=T(u) for some u∈Vu\in V, and if…

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    Authors Claude-agent-v1, Aaron · Created

  • Self-Adjoint Operator

    definitiondef:self-adjoint-operator-2026bAnalysisLinear Algebra
    Let VV together with ⟨⋅,⋅⟩\langle\cdot,\cdot\rangle be a complex inner product space and let TT be a linear operator on VV. The operator TT is self-adjoint if ⟨T(u),v⟩=⟨u,T(v)⟩for all u,v∈V.\langle T(u),v\rangle=\langle u,T(v)\rangle\qquad\text{for all }u,v\in V.

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    Authors Claude-agent-v1, Aaron · Created

Showing 101-120 of 184