Spectral · section of the QIQT-H book

QIQTH.Spectral.SpectralTheorem

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Spectral · entries 670–752 of 1000

Lemma 670 (congr_simp).  source ↗

s=s_1(zz_1:H),z=z_1qThasz=qThas_1z_1s = \mathrm{s\_1} \to \forall (z \mathrm{z\_1} : H), z = \mathrm{z\_1} \to \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-qform}{q}\,T\,\mathrm{ha}\,s\,z = \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-qform}{q}\,T\,\mathrm{ha}\,\mathrm{s\_1}\,\mathrm{z\_1}

Proof. Immediate from the definitions. \square

Used by qForm_neg, bForm_zero_right.

Lemma 671 (congr_simp).  source ↗

s=s_1(uu_1:H),u=u_1(vv_1:H),v=v_1bThasuv=bThas_1u_1v_1s = \mathrm{s\_1} \to \forall (u \mathrm{u\_1} : H), u = \mathrm{u\_1} \to \forall (v \mathrm{v\_1} : H), v = \mathrm{v\_1} \to \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-bform}{b}\,T\,\mathrm{ha}\,s\,u\,v = \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-bform}{b}\,T\,\mathrm{ha}\,\mathrm{s\_1}\,\mathrm{u\_1}\,\mathrm{v\_1}

Proof. Immediate from the definitions. \square

Used by bForm_neg_right.

Lemma 672 (congr_simp).  source ↗

s=s_1EThas=EThas_1s = \mathrm{s\_1} \to \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specproj}{E}\,T\,\mathrm{ha}\,s = \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specproj}{E}\,T\,\mathrm{ha}\,\mathrm{s\_1}

Proof. Immediate from the definitions. \square

Used by specProj_finset_sum.

Lemma 673 (congr_simp).  source ↗

x=x_1μspThax=μspThax_1x = \mathrm{x\_1} \to \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,x = \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,\mathrm{x\_1}

Proof. Immediate from the definitions. \square

Used by specMeasure_zero.

Definition 674 (specFunctional).  source ↗

The scalar spectral functional as an ℝ-linear map on compactly-supported continuous functions on the spectrum: f ↦ re ⟪x, f(T) x⟫, where f(T) := cfcHom ha f.

specFunctionalHTx  :=  {toFun:=λfre(x,((cfcHomha)f.toContinuousMap)x),map_add:=,map_smul:=}\mathrm{specFunctional}\,H\,T\,x \;:=\; \{\mathrm{toFun} :=\lambda f \mapsto \mathrm{re}\,(\langle {x},{((\mathrm{cfcHom}\,\mathrm{ha})\,f.\mathrm{toContinuousMap})\,x}\rangle) , \mathrm{map\_add}^{\prime} :=\cdots , \mathrm{map\_smul}^{\prime} :=\cdots \}

Used by specPLM.

Definition 675 (specPLM).  source ↗

The scalar spectral functional bundled as a positive linear functional Λ_x : C_c(spectrum ℝ T, ℝ) →ₚ[ℝ] ℝ.

Used by specMeasure, integral_specMeasure, instIsFiniteMeasureElemRealSpectrumContinuousLinearMapComplexIdSpecMeasure.

Definition 676 (specMeasure).  source ↗

The scalar spectral measure μ_x of a self-adjoint T at a vector x: the Riesz–Markov measure of the positive functional Λ_x = specPLM.

μspHTx  :=  rieszMeasure(specPLMThax)\mu_{\mathrm{sp}}\,H\,T\,x \;:=\; \mathrm{rieszMeasure}\,(\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specplm}{\mathrm{specPLM}}\,T\,\mathrm{ha}\,x)

Used by congr_simp, integral_specMeasure, instIsFiniteMeasureElemRealSpectrumContinuousLinearMapComplexIdSpecMeasure, specMeasure_real_univ, specMeasure_real_le, specMeasure_smul, specMeasure_parallelogram, specMeasure_add, and 22 more.

Lemma 677 (integral_specMeasure).  source ↗

Defining property of the scalar spectral measure (Riesz–Markov representation): ∫ f dμ_x = re ⟪x, f(T) x⟫ for every f ∈ C_c(spectrum ℝ T, ℝ).

(s:(spRT)),fsμspThax=re(x,((cfcHomha)f.toContinuousMap)x)\int (s : (\mathrm{sp}\,\mathbb{R}\,T)), f\,s \partial \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,x = \mathrm{re}\,(\langle {x},{((\mathrm{cfcHom}\,\mathrm{ha})\,f.\mathrm{toContinuousMap})\,x}\rangle)

Proof. By specPLM. \square

Used by specMeasure_real_univ, specMeasure_smul, specMeasure_parallelogram, specMeasure_add, integral_specMeasure_cont, re_inner_T_eq_integral.

Lemma 678 (instIsFiniteMeasureElemRealSpectrumContinuousLinearMapComplexIdSpecMeasure).  source ↗

μ_x is a finite measure (the spectrum is compact).

IsFiniteMeasure(μspThax)\mathrm{IsFiniteMeasure}\,(\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,x)

Proof. By specPLM. \square

Used by specMeasure_real_le, specMeasure_smul, specMeasure_parallelogram, specMeasure_add, qForm_parallelogram, qForm_add, qForm_union, specProj_hasSum, and 6 more.

Lemma 679 (specMeasure_real_univ).  source ↗

Total mass of the scalar spectral measure — the scalar-level E(univ) = 1: μ_x(univ) = ‖x‖² (as a real number), since 1(T) = 1 and re ⟪x, x⟫ = ‖x‖².

(μspThax).real=x2(\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,x).\mathrm{real} = {\|x\|}^{2}

Proof. By integral_specMeasure. \square

Used by specMeasure_real_le, qForm_univ.

Lemma 680 (specMeasure_real_le).  source ↗

Per-set bound for the scalar spectral measure: μ_z(B) ≤ ‖z‖² for every set B (monotonicity against the total mass μ_z(univ) = ‖z‖²). This feeds the operator-norm bound on the spectral projections E(B).

(μspThaz).realBz2(\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,z).\mathrm{real}\,B \le {\|z\|}^{2}

Proof. By instIsFiniteMeasureElemRealSpectrumContinuousLinearMapComplexIdSpecMeasure, specMeasure_real_univ. \square

Used by bForm_abs_le, specProj_le_one.

Lemma 681 (specMeasure_smul).  source ↗

Scaling law of the scalar spectral measure: μ_{c•x} = ‖c‖² · μ_x.

μspTha(cx)=c+2μspThax\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,(c \cdot x) = {\|c\|_{+}}^{2} \cdot \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,x

Proof. By integral_specMeasure, instIsFiniteMeasureElemRealSpectrumContinuousLinearMapComplexIdSpecMeasure. \square

Used by specMeasure_zero, qForm_smul.

Lemma 682 (specMeasure_parallelogram).  source ↗

Parallelogram law of the scalar spectral measure: μ_{x+y} + μ_{x−y} = 2·μ_x + 2·μ_y (the cross terms of the quadratic form cancel). Holds for any operator; the engine for sesquilinearity of the polarized form.

μspTha(x+y)+μspTha(xy)=2μspThax+2μspThay\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,(x + y) + \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,(x - y) = 2 \cdot \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,x + 2 \cdot \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,y

Proof. By integral_specMeasure, instIsFiniteMeasureElemRealSpectrumContinuousLinearMapComplexIdSpecMeasure. \square

Used by qForm_parallelogram.

Lemma 683 (specMeasure_add).  source ↗

Additivity engine (measure level): the second-difference identity μ_{x+a+b} + μ_{x−a} + μ_{x−b} = μ_{x−a−b} + μ_{x+a} + μ_{x+b} (both sides expand to 3q(x)+2q(a)+2q(b)+g(a,b) for the quadratic form q and its symmetric bilinear part g). Applied with (a,b)=(y₁,y₂) and (a,b)=(I·y₁, I·y₂) it yields additivity of the polarized spectral form in y.

μspTha(x+a+b)+μspTha(xa)+μspTha(xb)=μspTha(xab)+μspTha(x+a)+μspTha(x+b)\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,(x + a + b) + \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,(x - a) + \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,(x - b) = \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,(x - a - b) + \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,(x + a) + \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,(x + b)

Proof. By integral_specMeasure, instIsFiniteMeasureElemRealSpectrumContinuousLinearMapComplexIdSpecMeasure. \square

Used by qForm_add.

Definition 684 (qForm).  source ↗

The diagonal quadratic form q_s(z) = μ_z(s) (real, nonnegative).

qHTsz  :=  (μspThaz).realsq\,H\,T\,s\,z \;:=\; (\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,z).\mathrm{real}\,s

Used by congr_simp, qForm_nonneg, qForm_zero, qForm_smul, qForm_neg, qForm_parallelogram, qForm_add, bForm, and 23 more.

Lemma 685 (qForm_nonneg).  source ↗

0qThasz0 \le \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-qform}{q}\,T\,\mathrm{ha}\,s\,z

Proof. By specMeasure. \square

Used by bForm_sq_le, bForm_abs_le, specProj_isPositive.

Lemma 686 (specMeasure_zero).  source ↗

μ_0 = 0 (the zero vector gives the zero measure).

μspTha0=0\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,0 = 0

Proof. By congr_simp, specMeasure_smul. \square

Used by qForm_zero.

Lemma 687 (qForm_zero).  source ↗

qThas0=0\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-qform}{q}\,T\,\mathrm{ha}\,s\,0 = 0

Proof. By specMeasure, specMeasure_zero. \square

Used by bForm_self.

Lemma 688 (qForm_smul).  source ↗

qThas(cz)=c2qThasz\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-qform}{q}\,T\,\mathrm{ha}\,s\,(c \cdot z) = {\|c\|}^{2} \cdot \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-qform}{q}\,T\,\mathrm{ha}\,s\,z

Proof. By specMeasure, specMeasure_smul. \square

Used by qForm_neg, bForm_self, qForm_real_smul, bForm_I_smul.

Lemma 689 (qForm_neg).  source ↗

qThas(z)=qThasz\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-qform}{q}\,T\,\mathrm{ha}\,s\,(-z) = \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-qform}{q}\,T\,\mathrm{ha}\,s\,z

Proof. By congr_simp, qForm_smul. \square

Used by bForm_comm.

Lemma 690 (qForm_parallelogram).  source ↗

qThas(x+y)+qThas(xy)=2qThasx+2qThasy\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-qform}{q}\,T\,\mathrm{ha}\,s\,(x + y) + \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-qform}{q}\,T\,\mathrm{ha}\,s\,(x - y) = 2 \cdot \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-qform}{q}\,T\,\mathrm{ha}\,s\,x + 2 \cdot \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-qform}{q}\,T\,\mathrm{ha}\,s\,y

Proof. By specMeasure, instIsFiniteMeasureElemRealSpectrumContinuousLinearMapComplexIdSpecMeasure, specMeasure_parallelogram. \square

Used by qForm_add_expand.

Lemma 691 (qForm_add).  source ↗

qThas(x+a+b)+qThas(xa)+qThas(xb)=qThas(xab)+qThas(x+a)+qThas(x+b)\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-qform}{q}\,T\,\mathrm{ha}\,s\,(x + a + b) + \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-qform}{q}\,T\,\mathrm{ha}\,s\,(x - a) + \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-qform}{q}\,T\,\mathrm{ha}\,s\,(x - b) = \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-qform}{q}\,T\,\mathrm{ha}\,s\,(x - a - b) + \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-qform}{q}\,T\,\mathrm{ha}\,s\,(x + a) + \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-qform}{q}\,T\,\mathrm{ha}\,s\,(x + b)

Proof. By specMeasure, instIsFiniteMeasureElemRealSpectrumContinuousLinearMapComplexIdSpecMeasure, specMeasure_add. \square

Used by bForm_add_right.

Definition 692 (bForm).  source ↗

The polarized bilinear form b_s(u,v) = ¼(q_s(u+v) − q_s(u−v)).

bHTsuv  :=  (qThas(u+v)qThas(uv))/4b\,H\,T\,s\,u\,v \;:=\; (\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-qform}{q}\,T\,\mathrm{ha}\,s\,(u + v) - \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-qform}{q}\,T\,\mathrm{ha}\,s\,(u - v)) / 4

Used by congr_simp, qForm_add_expand, bForm_self, bForm_comm, bForm_add_right, bForm_zero_right, bFormRight, bForm_sq_le, and 22 more.

Lemma 693 (qForm_add_expand).  source ↗

Expansion identity: q_s(p+q) = q_s(p) + q_s(q) + 2 b_s(p,q) (from the parallelogram law).

qThas(p+q)=qThasp+qThasq+2bThaspq\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-qform}{q}\,T\,\mathrm{ha}\,s\,(p + q) = \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-qform}{q}\,T\,\mathrm{ha}\,s\,p + \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-qform}{q}\,T\,\mathrm{ha}\,s\,q + 2 \cdot \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-bform}{b}\,T\,\mathrm{ha}\,s\,p\,q

Proof. By qForm_parallelogram. \square

Used by bForm_sq_le.

Lemma 694 (bForm_self).  source ↗

b_s(u,u) = q_s(u).

bThasuu=qThasu\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-bform}{b}\,T\,\mathrm{ha}\,s\,u\,u = \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-qform}{q}\,T\,\mathrm{ha}\,s\,u

Proof. By qForm_zero, qForm_smul. \square

Used by reApplyInnerSelf_specProj.

Lemma 695 (bForm_comm).  source ↗

b_s is symmetric.

bThasuv=bThasvu\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-bform}{b}\,T\,\mathrm{ha}\,s\,u\,v = \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-bform}{b}\,T\,\mathrm{ha}\,s\,v\,u

Proof. By qForm, qForm_neg. \square

Used by cForm_hermitian, bForm_sub_left.

Lemma 696 (bForm_add_right).  source ↗

b_s is additive in its right argument.

bThasu(v+w)=bThasuv+bThasuw\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-bform}{b}\,T\,\mathrm{ha}\,s\,u\,(v + w) = \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-bform}{b}\,T\,\mathrm{ha}\,s\,u\,v + \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-bform}{b}\,T\,\mathrm{ha}\,s\,u\,w

Proof. By qForm, qForm_add. \square

Used by bFormRight, bForm_sub_right, cForm_add_right.

Lemma 697 (qForm_real_smul).  source ↗

Real-scalar version of the scaling law: q_s(r•z) = r²·q_s(z).

qThas(rz)=r2qThasz\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-qform}{q}\,T\,\mathrm{ha}\,s\,(r \cdot z) = {r}^{2} \cdot \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-qform}{q}\,T\,\mathrm{ha}\,s\,z

Proof. By qForm_smul. \square

Used by bForm_sq_le.

Lemma 698 (bForm_zero_right).  source ↗

bThasu0=0\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-bform}{b}\,T\,\mathrm{ha}\,s\,u\,0 = 0

Proof. By congr_simp, qForm. \square

Used by bFormRight.

Definition 699 (bFormRight).  source ↗

b_s(u, ·) bundled as an additive homomorphism (used for ℚ-homogeneity in Cauchy–Schwarz).

bFormRightHTsu  :=  {toFun:=λwbThasuw,map_zero:=,map_add:=}\mathrm{bFormRight}\,H\,T\,s\,u \;:=\; \{\mathrm{toFun} :=\lambda w \mapsto \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-bform}{b}\,T\,\mathrm{ha}\,s\,u\,w , \mathrm{map\_zero}^{\prime} :=\cdots , \mathrm{map\_add}^{\prime} :=\cdots \}

Used by bForm_sq_le, bForm_real_smul_right.

Lemma 700 (bForm_sq_le).  source ↗

Cauchy–Schwarz for the spectral form: b_s(u,v)² ≤ q_s(u)·q_s(v). Because q_s ≥ 0, the quadratic t ↦ q_s(u + t•v) = q_s(v)·t² + 2 b_s(u,v)·t + q_s(u) is nonnegative on (hence on by density), so its discriminant is ≤ 0.

bThasuv2qThasuqThasv{\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-bform}{b}\,T\,\mathrm{ha}\,s\,u\,v}^{2} \le \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-qform}{q}\,T\,\mathrm{ha}\,s\,u \cdot \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-qform}{q}\,T\,\mathrm{ha}\,s\,v

Proof. By qForm_nonneg, qForm_add_expand, qForm_real_smul, bFormRight. \square

Used by bForm_abs_le.

Lemma 701 (bForm_sub_right).  source ↗

b_s is subtractive in its right argument.

bThasu(vw)=bThasuvbThasuw\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-bform}{b}\,T\,\mathrm{ha}\,s\,u\,(v - w) = \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-bform}{b}\,T\,\mathrm{ha}\,s\,u\,v - \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-bform}{b}\,T\,\mathrm{ha}\,s\,u\,w

Proof. By bForm_add_right. \square

Used by bForm_continuous_right, bForm_sub_left.

Lemma 702 (bForm_abs_le).  source ↗

Boundedness of the spectral form: |b_s(u,v)| ≤ ‖u‖·‖v‖ (from Cauchy–Schwarz and q_s(z) ≤ ‖z‖²).

bThasuvuv|\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-bform}{b}\,T\,\mathrm{ha}\,s\,u\,v| \le \|u\| \cdot \|v\|

Proof. By specMeasure_real_le, qForm, qForm_nonneg, bForm_sq_le. \square

Used by bForm_continuous_right, cForm_norm_le.

Lemma 703 (bForm_continuous_right).  source ↗

b_s(u, ·) is continuous (Lipschitz with constant ‖u‖).

ContinuousλvbThasuv\mathrm{Continuous}\,\lambda v \mapsto \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-bform}{b}\,T\,\mathrm{ha}\,s\,u\,v

Proof. By bForm_sub_right, bForm_abs_le. \square

Used by bForm_real_smul_right.

Lemma 704 (bForm_real_smul_right).  source ↗

ℝ-homogeneity of b_s(u, ·) (continuity + map_real_smul).

bThasu(rv)=rbThasuv\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-bform}{b}\,T\,\mathrm{ha}\,s\,u\,(r \cdot v) = r \cdot \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-bform}{b}\,T\,\mathrm{ha}\,s\,u\,v

Proof. By bFormRight, bForm_continuous_right. \square

Used by bForm_neg_right.

Lemma 705 (bForm_neg_right).  source ↗

bThasu(v)=bThasuv\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-bform}{b}\,T\,\mathrm{ha}\,s\,u\,(-v) = -\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-bform}{b}\,T\,\mathrm{ha}\,s\,u\,v

Proof. By congr_simp, bForm_real_smul_right. \square

Used by bForm_I_comm.

Lemma 706 (bForm_I_smul).  source ↗

b_s is invariant under simultaneous multiplication by i: b_s(I•u, I•v) = b_s(u,v) (from the i-invariance q_s(I•z) = q_s(z)).

bThas(iu)(iv)=bThasuv\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-bform}{b}\,T\,\mathrm{ha}\,s\,(i \cdot u)\,(i \cdot v) = \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-bform}{b}\,T\,\mathrm{ha}\,s\,u\,v

Proof. By qForm, qForm_smul. \square

Used by bForm_I_comm.

Lemma 707 (bForm_I_comm).  source ↗

The i-twist: b_s(I•x, y) = − b_s(x, I•y).

bThas(ix)y=bThasx(iy)\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-bform}{b}\,T\,\mathrm{ha}\,s\,(i \cdot x)\,y = -\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-bform}{b}\,T\,\mathrm{ha}\,s\,x\,(i \cdot y)

Proof. By bForm_neg_right, bForm_I_smul. \square

Used by cForm_hermitian.

Definition 708 (cForm).  source ↗

The complex spectral form c_s(x,y) = b_s(x,y) − i·b_s(x, I•y); its Riesz representation will be the spectral projection E(s), with ⟪E(s) x, y⟫ = c_s(x,y).

cHTsxy  :=  (bThasxy)i(bThasx(iy))c\,H\,T\,s\,x\,y \;:=\; (\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-bform}{b}\,T\,\mathrm{ha}\,s\,x\,y) - i \cdot (\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-bform}{b}\,T\,\mathrm{ha}\,s\,x\,(i \cdot y))

Used by cForm_add_right, cForm_norm_le, cFormCLM, cFormCLM_norm_le, inner_specProj, cForm_empty, specProj_empty, cForm_hermitian, and 8 more.

Lemma 709 (cForm_add_right).  source ↗

cThasx(y+z)=cThasxy+cThasxz\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-cform}{c}\,T\,\mathrm{ha}\,s\,x\,(y + z) = \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-cform}{c}\,T\,\mathrm{ha}\,s\,x\,y + \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-cform}{c}\,T\,\mathrm{ha}\,s\,x\,z

Proof. By bForm, bForm_add_right. \square

Used by cFormCLM, cFormCLM_norm_le.

Lemma 710 (cForm_norm_le).  source ↗

Norm bound: ‖c_s(x,y)‖ ≤ 2·‖x‖·‖y‖.

cThasxy2xy\|\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-cform}{c}\,T\,\mathrm{ha}\,s\,x\,y\| \le 2 \cdot \|x\| \cdot \|y\|

Proof. By bForm, bForm_abs_le. \square

Used by cFormCLM, cFormCLM_norm_le.

Definition 711 (cFormCLM).  source ↗

c_s(x, ·) bundled as a continuous ℂ-linear functional H →L[ℂ] ℂ.

cFormCLMHTsx  :=  {toFun:=λycThasxy,map_add:=,map_smul:=}.mkContinuous(2x)\mathrm{cFormCLM}\,H\,T\,s\,x \;:=\; \{\mathrm{toFun} :=\lambda y \mapsto \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-cform}{c}\,T\,\mathrm{ha}\,s\,x\,y , \mathrm{map\_add}^{\prime} :=\cdots , \mathrm{map\_smul}^{\prime} :=\cdots \}.\mathrm{mkContinuous}\,(2 \cdot \|x\|)\,\cdots

Used by cFormCLM_norm_le, specProj, inner_specProj.

Lemma 712 (cFormCLM_norm_le).  source ↗

cFormCLMThasx2x\|\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-cformclm}{\mathrm{cFormCLM}}\,T\,\mathrm{ha}\,s\,x\| \le 2 \cdot \|x\|

Proof. By cForm, cForm_add_right, cForm_norm_le. \square

Used by specProj, inner_specProj.

Definition 713 (specProj).  source ↗

The spectral projection E(s) : H →L[ℂ] H, obtained by Riesz-representing the bounded sesquilinear form c_s (⟪E(s) x, y⟫ = c_s(x,y)).

EHTs  :=  continuousLinearMapOfBilin({toFun:=λxcFormCLMThasx,map_add:=,map_smul:=}.mkContinuous2)E\,H\,T\,s \;:=\; \mathrm{continuousLinearMapOfBilin}\,(\{\mathrm{toFun} :=\lambda x \mapsto \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-cformclm}{\mathrm{cFormCLM}}\,T\,\mathrm{ha}\,s\,x , \mathrm{map\_add}^{\prime} :=\cdots , \mathrm{map\_smul}^{\prime} :=\cdots \}.\mathrm{mkContinuous}\,2\,\cdots )

Used by congr_simp, inner_specProj, specProj_empty, specProj_isSelfAdjoint, specProj_univ, reApplyInnerSelf_specProj, specProj_isPositive, specProj_union_disjoint, and 10 more.

Lemma 714 (inner_specProj).  source ↗

Defining identity of the spectral projection: ⟪E(s) x, y⟫ = c_s(x,y).

(EThas)x,y=cThasxy\langle {(\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specproj}{E}\,T\,\mathrm{ha}\,s)\,x},{y}\rangle = \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-cform}{c}\,T\,\mathrm{ha}\,s\,x\,y

Proof. By cFormCLM, cFormCLM_norm_le. \square

Used by specProj_empty, specProj_isSelfAdjoint, specProj_univ, reApplyInnerSelf_specProj, specProj_union_disjoint, re_inner_cfcHom_specProj, specProj_inter.

Lemma 715 (cForm_empty).  source ↗

c_∅ = 0.

cThaxy=0\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-cform}{c}\,T\,\mathrm{ha}\,\emptyset \,x\,y = 0

Proof. By specMeasure, qForm, bForm. \square

Used by specProj_empty.

Lemma 716 (specProj_empty).  source ↗

E(∅) = 0.

ETha=0\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specproj}{E}\,T\,\mathrm{ha}\,\emptyset = 0

Proof. By cForm, inner_specProj, cForm_empty. \square

Used by specProj_finset_sum, PVM_of_selfAdjoint.

Lemma 717 (cForm_hermitian).  source ↗

Hermitian symmetry of the form: conj(c_s(y,x)) = c_s(x,y).

(starRingEndC)(cThasyx)=cThasxy(\mathrm{starRingEnd}\,\mathbb{C})\,(\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-cform}{c}\,T\,\mathrm{ha}\,s\,y\,x) = \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-cform}{c}\,T\,\mathrm{ha}\,s\,x\,y

Proof. By bForm, bForm_comm, bForm_I_comm. \square

Used by specProj_isSelfAdjoint.

Lemma 718 (specProj_isSelfAdjoint).  source ↗

E(s) is self-adjoint.

IsSelfAdjoint(EThas)\mathrm{IsSelfAdjoint}\,(\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specproj}{E}\,T\,\mathrm{ha}\,s)

Proof. By cForm, inner_specProj, cForm_hermitian. \square

Used by specProj_isPositive, specProj_le_one, norm_specProj_sq_le, re_inner_cfcHom_specProj, specProj_inter, PVM_of_selfAdjoint, scalarMeasure_eq_specMeasure.

Lemma 719 (qForm_univ).  source ↗

q_univ(z) = ‖z‖².

qThaz=z2\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-qform}{q}\,T\,\mathrm{ha}\,z = {\|z\|}^{2}

Proof. By specMeasure_real_univ. \square

Used by bForm_univ.

Lemma 720 (bForm_univ).  source ↗

b_univ(x,y) = re ⟪x,y⟫ (polarization of the norm).

bThaxy=re(x,y)\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-bform}{b}\,T\,\mathrm{ha}\,x\,y = \mathrm{re}\,(\langle {x},{y}\rangle)

Proof. By qForm, qForm_univ. \square

Used by cForm_univ.

Lemma 721 (cForm_univ).  source ↗

c_univ(x,y) = ⟪x,y⟫.

cThaxy=x,y\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-cform}{c}\,T\,\mathrm{ha}\,x\,y = \langle {x},{y}\rangle

Proof. By bForm, bForm_univ. \square

Used by specProj_univ.

Lemma 722 (specProj_univ).  source ↗

E(univ) = 1.

ETha=1\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specproj}{E}\,T\,\mathrm{ha} = 1

Proof. By cForm, inner_specProj, cForm_univ. \square

Used by PVM_of_selfAdjoint.

Lemma 723 (reApplyInnerSelf_specProj).  source ↗

The diagonal of the spectral form is the (real, nonnegative) quadratic form: re ⟪E(s) x, x⟫ = q_s(x).

(EThas).reApplyInnerSelfx=qThasx(\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specproj}{E}\,T\,\mathrm{ha}\,s).\mathrm{reApplyInnerSelf}\,x = \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-qform}{q}\,T\,\mathrm{ha}\,s\,x

Proof. By bForm, bForm_self, cForm, inner_specProj. \square

Used by specProj_isPositive, specProj_le_one, norm_specProj_sq_le, scalarMeasure_eq_specMeasure.

Lemma 724 (specProj_isPositive).  source ↗

E(s) is a positive operator.

(EThas).IsPositive(\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specproj}{E}\,T\,\mathrm{ha}\,s).\mathrm{IsPositive}

Proof. By qForm, qForm_nonneg, specProj_isSelfAdjoint, reApplyInnerSelf_specProj. \square

Used by norm_specProj_sq_le.

Lemma 725 (qForm_union).  source ↗

Finite additivity of the diagonal form on disjoint sets.

DisjointstMeasurableSett(z:H),qTha(st)z=qThasz+qThatz\mathrm{Disjoint}\,s\,t \to \mathrm{MeasurableSet}\,t \to \forall (z : H), \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-qform}{q}\,T\,\mathrm{ha}\,(s \cup t)\,z = \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-qform}{q}\,T\,\mathrm{ha}\,s\,z + \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-qform}{q}\,T\,\mathrm{ha}\,t\,z

Proof. By specMeasure, instIsFiniteMeasureElemRealSpectrumContinuousLinearMapComplexIdSpecMeasure. \square

Used by cForm_union_disjoint.

Lemma 726 (cForm_union_disjoint).  source ↗

Finite additivity of the complex form on disjoint sets.

DisjointstMeasurableSett(xy:H),cTha(st)xy=cThasxy+cThatxy\mathrm{Disjoint}\,s\,t \to \mathrm{MeasurableSet}\,t \to \forall (x y : H), \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-cform}{c}\,T\,\mathrm{ha}\,(s \cup t)\,x\,y = \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-cform}{c}\,T\,\mathrm{ha}\,s\,x\,y + \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-cform}{c}\,T\,\mathrm{ha}\,t\,x\,y

Proof. By qForm, bForm, qForm_union. \square

Used by specProj_union_disjoint.

Lemma 727 (specProj_union_disjoint).  source ↗

Finite additivity of the spectral projection on disjoint measurable sets: E(s ∪ t) = E(s) + E(t).

DisjointstMeasurableSettETha(st)=EThas+EThat\mathrm{Disjoint}\,s\,t \to \mathrm{MeasurableSet}\,t \to \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specproj}{E}\,T\,\mathrm{ha}\,(s \cup t) = \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specproj}{E}\,T\,\mathrm{ha}\,s + \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specproj}{E}\,T\,\mathrm{ha}\,t

Proof. By cForm, inner_specProj, cForm_union_disjoint. \square

Used by specProj_finset_sum, specProj_hasSum.

Lemma 728 (specProj_le_one).  source ↗

E(s) ≤ 1 (the spectral projection is a contraction in the Loewner order): 1 − E(s) is positive since re ⟪(1−E(s)) x, x⟫ = ‖x‖² − q_s(x) ≥ 0.

EThas1\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specproj}{E}\,T\,\mathrm{ha}\,s \le 1

Proof. By specMeasure_real_le, qForm, specProj_isSelfAdjoint, reApplyInnerSelf_specProj. \square

Used by norm_specProj_sq_le.

Lemma 729 (norm_specProj_sq_le).  source ↗

Effect estimate: for the positive contraction E(s), ‖E(s) x‖² ≤ q_s(x). (From E(s)² ≤ E(s), i.e. E(s)·(1−E(s)) ≥ 0 for commuting positives.)

(EThas)x2qThasx{\|(\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specproj}{E}\,T\,\mathrm{ha}\,s)\,x\|}^{2} \le \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-qform}{q}\,T\,\mathrm{ha}\,s\,x

Proof. By specProj_isSelfAdjoint, reApplyInnerSelf_specProj, specProj_isPositive, specProj_le_one. \square

Used by specProj_hasSum.

Lemma 730 (specProj_finset_sum).  source ↗

Finite (Finset) additivity of the spectral projection over pairwise-disjoint measurable sets: ∑ n ∈ F, E(A n) = E(⋃ n ∈ F, A n).

((n:N),MeasurableSet(An))(PairwiseλmnDisjoint(Am)(An))(F:FinsetN),nFETha(An)=ETha(nF,An)(\forall (n : \mathbb{N}), \mathrm{MeasurableSet}\,(A\,n)) \to (\mathrm{Pairwise}\,\lambda m n \mapsto \mathrm{Disjoint}\,(A\,m)\,(A\,n)) \to \forall (F : \mathrm{Finset}\,\mathbb{N}), \sum_{n F} \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specproj}{E}\,T\,\mathrm{ha}\,(A\,n) = \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specproj}{E}\,T\,\mathrm{ha}\,(\bigcup n\in F, A\,n)

Proof. By congr_simp, specProj_empty, specProj_union_disjoint. \square

Used by specProj_hasSum.

Lemma 731 (specProj_hasSum).  source ↗

σ-additivity of the spectral projection (strong/SOT): for pairwise-disjoint measurable A, HasSum (fun n => E(A n) x) (E(⋃ n, A n) x). Proved by a norm-tail estimate: ‖∑_{n∈s} E(A n) x − E(⋃A) x‖² ≤ q_{(⋃A)∖(⋃_s)}(x) = q_{⋃A}(x) − ∑_{n∈s} q_{A n}(x) → 0 (effect estimate + scalar measure σ-additivity).

((n:N),MeasurableSet(An))(PairwiseλmnDisjoint(Am)(An))(x:H),HasSum(λn(ETha(An))x)((ETha(n,An))x)(\forall (n : \mathbb{N}), \mathrm{MeasurableSet}\,(A\,n)) \to (\mathrm{Pairwise}\,\lambda m n \mapsto \mathrm{Disjoint}\,(A\,m)\,(A\,n)) \to \forall (x : H), \mathrm{HasSum}\,(\lambda n \mapsto (\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specproj}{E}\,T\,\mathrm{ha}\,(A\,n))\,x)\,((\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specproj}{E}\,T\,\mathrm{ha}\,(\bigcup n, A\,n))\,x)

Proof. By specMeasure, instIsFiniteMeasureElemRealSpectrumContinuousLinearMapComplexIdSpecMeasure, qForm, specProj_union_disjoint, norm_specProj_sq_le, specProj_finset_sum. \square

Used by PVM_of_selfAdjoint.

Lemma 732 (inner_cfcHom_mul).  source ↗

cfcHom-multiplicativity in the inner product: ⟪g(T)x, h(T)y⟫ = ⟪x, (g·h)(T)y⟫ (self-adjointness of g(T) + cfcHom is an algebra hom). This is the clean engine for the off-diagonal measure identity ν_{g(T)x,y} = g·ν_{x,y} that yields E_inter directly.

((cfcHomha)g)x,((cfcHomha)h)y=x,((cfcHomha)(gh))y\langle {((\mathrm{cfcHom}\,\mathrm{ha})\,g)\,x},{((\mathrm{cfcHom}\,\mathrm{ha})\,h)\,y}\rangle = \langle {x},{((\mathrm{cfcHom}\,\mathrm{ha})\,(g \cdot h))\,y}\rangle

Proof. Immediate from the definitions. \square

Used by specMeasure_engine.

Lemma 733 (integral_specMeasure_cont).  source ↗

Bridge: the scalar-measure integral of a continuous h is re ⟪z, h(T) z⟫ (the C_c version integral_specMeasure specialised via HasCompactSupport.of_compactSpace).

(ω:(spRT)),hωμspThaz=re(z,((cfcHomha)h)z)\int (\omega : (\mathrm{sp}\,\mathbb{R}\,T)), h\,\omega \partial \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,z = \mathrm{re}\,(\langle {z},{((\mathrm{cfcHom}\,\mathrm{ha})\,h)\,z}\rangle)

Proof. By integral_specMeasure. \square

Used by specMeasure_engine, integral_specMeasure_polarization.

Lemma 734 (specMeasure_engine).  source ↗

Off-diagonal engine (integral form): for continuous g, h and any vectors x, v, (∫h dμ_{g(T)x+v} − ∫h dμ_{g(T)x−v}) = (∫(h·g) dμ_{x+v} − ∫(h·g) dμ_{x−v}). Both sides equal 4·re⟪x, (h·g)(T) v⟫ (polarization + inner_cfcHom_mul).

(ω:(spRT)),hωμspTha(((cfcHomha)g)x+v)(ω:(spRT)),hωμspTha(((cfcHomha)g)xv)=(ω:(spRT)),(hg)ωμspTha(x+v)(ω:(spRT)),(hg)ωμspTha(xv)\int (\omega : (\mathrm{sp}\,\mathbb{R}\,T)), h\,\omega \partial \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,(((\mathrm{cfcHom}\,\mathrm{ha})\,g)\,x + v) - \int (\omega : (\mathrm{sp}\,\mathbb{R}\,T)), h\,\omega \partial \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,(((\mathrm{cfcHom}\,\mathrm{ha})\,g)\,x - v) = \int (\omega : (\mathrm{sp}\,\mathbb{R}\,T)), (h \cdot g)\,\omega \partial \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,(x + v) - \int (\omega : (\mathrm{sp}\,\mathbb{R}\,T)), (h \cdot g)\,\omega \partial \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,(x - v)

Proof. By inner_cfcHom_mul, integral_specMeasure_cont. \square

Used by specMeasure_engine_measure.

Lemma 735 (specMeasure_engine_measure).  source ↗

Engine, measure form (g ≥ 0): μ_{g(T)x+v} + (μ_{x−v}·g) = μ_{g(T)x−v} + (μ_{x+v}·g), where ·g is withDensity (ENNReal.ofReal ∘ g). Lifts specMeasure_engine to a measure identity by Riesz–Markov uniqueness.

((ω:(spRT)),0gω)(xv:H),(μspTha(((cfcHomha)g)x+v)+(μspTha(xv)).wdλωgω)=μspTha(((cfcHomha)g)xv)+(μspTha(x+v)).wdλωgω(\forall (\omega : (\mathrm{sp}\,\mathbb{R}\,T)), 0 \le g\,\omega) \to \forall (x v : H), (\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,(((\mathrm{cfcHom}\,\mathrm{ha})\,g)\,x + v) + (\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,(x - v)).\mathrm{wd}\,\lambda \omega \mapsto {{g\,\omega}}) = \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,(((\mathrm{cfcHom}\,\mathrm{ha})\,g)\,x - v) + (\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,(x + v)).\mathrm{wd}\,\lambda \omega \mapsto {{g\,\omega}}

Proof. By instIsFiniteMeasureElemRealSpectrumContinuousLinearMapComplexIdSpecMeasure, specMeasure_engine. \square

Used by specMeasure_setEngine_nonneg.

Lemma 736 (withDensity_real_setIntegral).  source ↗

withDensity-to-setIntegral bridge: ((μ_z)·g).real s = ∫_s g dμ_z for g ≥ 0.

((ω:(spRT)),0gω)(z:H){s:Set(spRT)},MeasurableSets((μspThaz).wdλωgω).reals=(ω:(spRT))ins,gωμspThaz(\forall (\omega : (\mathrm{sp}\,\mathbb{R}\,T)), 0 \le g\,\omega) \to \forall (z : H) \{s : \mathrm{Set}\,(\mathrm{sp}\,\mathbb{R}\,T)\}, \mathrm{MeasurableSet}\,s \to ((\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,z).\mathrm{wd}\,\lambda \omega \mapsto {{g\,\omega}}).\mathrm{real}\,s = \int (\omega : (\mathrm{sp}\,\mathbb{R}\,T)) in s, g\,\omega \partial \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,z

Proof. Immediate from the definitions. \square

Used by specMeasure_setEngine_nonneg.

Lemma 737 (specMeasure_setEngine_nonneg).  source ↗

Set-level engine for g ≥ 0: q_s(g(T)x+v) − q_s(g(T)x−v) = ∫_s g dμ_{x+v} − ∫_s g dμ_{x−v} (the .real-at-s evaluation of specMeasure_engine_measure).

((ω:(spRT)),0gω)(xv:H){s:Set(spRT)},MeasurableSets(μspTha(((cfcHomha)g)x+v)).reals(μspTha(((cfcHomha)g)xv)).reals=(ω:(spRT))ins,gωμspTha(x+v)(ω:(spRT))ins,gωμspTha(xv)(\forall (\omega : (\mathrm{sp}\,\mathbb{R}\,T)), 0 \le g\,\omega) \to \forall (x v : H) \{s : \mathrm{Set}\,(\mathrm{sp}\,\mathbb{R}\,T)\}, \mathrm{MeasurableSet}\,s \to (\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,(((\mathrm{cfcHom}\,\mathrm{ha})\,g)\,x + v)).\mathrm{real}\,s - (\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,(((\mathrm{cfcHom}\,\mathrm{ha})\,g)\,x - v)).\mathrm{real}\,s = \int (\omega : (\mathrm{sp}\,\mathbb{R}\,T)) in s, g\,\omega \partial \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,(x + v) - \int (\omega : (\mathrm{sp}\,\mathbb{R}\,T)) in s, g\,\omega \partial \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,(x - v)

Proof. By instIsFiniteMeasureElemRealSpectrumContinuousLinearMapComplexIdSpecMeasure, specMeasure_engine_measure, withDensity_real_setIntegral. \square

Used by specMeasure_setEngine.

Lemma 738 (bForm_sub_left).  source ↗

b_s is subtractive in its left argument.

bThas(uw)v=bThasuvbThaswv\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-bform}{b}\,T\,\mathrm{ha}\,s\,(u - w)\,v = \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-bform}{b}\,T\,\mathrm{ha}\,s\,u\,v - \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-bform}{b}\,T\,\mathrm{ha}\,s\,w\,v

Proof. By bForm_comm, bForm_sub_right. \square

Used by specMeasure_setEngine.

Lemma 739 (specMeasure_setEngine).  source ↗

Set-level engine (general continuous g): q_s(g(T)x+v) − q_s(g(T)x−v) = ∫_s g dμ_{x+v} − ∫_s g dμ_{x−v}. Both sides are linear in g; extend the g≥0 case by g = (g+‖g‖) − ‖g‖.

MeasurableSets(μspTha(((cfcHomha)g)x+v)).reals(μspTha(((cfcHomha)g)xv)).reals=(ω:(spRT))ins,gωμspTha(x+v)(ω:(spRT))ins,gωμspTha(xv)\mathrm{MeasurableSet}\,s \to (\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,(((\mathrm{cfcHom}\,\mathrm{ha})\,g)\,x + v)).\mathrm{real}\,s - (\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,(((\mathrm{cfcHom}\,\mathrm{ha})\,g)\,x - v)).\mathrm{real}\,s = \int (\omega : (\mathrm{sp}\,\mathbb{R}\,T)) in s, g\,\omega \partial \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,(x + v) - \int (\omega : (\mathrm{sp}\,\mathbb{R}\,T)) in s, g\,\omega \partial \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,(x - v)

Proof. By instIsFiniteMeasureElemRealSpectrumContinuousLinearMapComplexIdSpecMeasure, qForm, bForm, specMeasure_setEngine_nonneg, bForm_sub_left. \square

Used by specProj_engine_measure.

Lemma 740 (re_inner_cfcHom_specProj).  source ↗

Diagonal–E(s) identity: re ⟪x, h(T)(E(s)v)⟫ = b_s(h(T)x, v) for continuous h. (Move h(T) and E(s) across by self-adjointness; the imaginary part of c_s drops under re.)

re(x,((cfcHomha)h)((EThas)v))=bThas(((cfcHomha)h)x)v\mathrm{re}\,(\langle {x},{((\mathrm{cfcHom}\,\mathrm{ha})\,h)\,((\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specproj}{E}\,T\,\mathrm{ha}\,s)\,v)}\rangle) = \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-bform}{b}\,T\,\mathrm{ha}\,s\,(((\mathrm{cfcHom}\,\mathrm{ha})\,h)\,x)\,v

Proof. By cForm, inner_specProj, specProj_isSelfAdjoint. \square

Used by specProj_engine_measure.

Lemma 741 (integral_specMeasure_polarization).  source ↗

Polarization at the scalar-measure level: ∫f dμ_{w+u} − ∫f dμ_{w−u} = 4·re⟪w, f(T)u⟫.

(ω:(spRT)),fωμspTha(w+u)(ω:(spRT)),fωμspTha(wu)=4re(w,((cfcHomha)f)u)\int (\omega : (\mathrm{sp}\,\mathbb{R}\,T)), f\,\omega \partial \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,(w + u) - \int (\omega : (\mathrm{sp}\,\mathbb{R}\,T)), f\,\omega \partial \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,(w - u) = 4 \cdot \mathrm{re}\,(\langle {w},{((\mathrm{cfcHom}\,\mathrm{ha})\,f)\,u}\rangle)

Proof. By integral_specMeasure_cont. \square

Used by specProj_engine_measure.

Lemma 742 (specProj_engine_measure).  source ↗

Final measure identity: μ_{x+E(s)v} + (μ_{x−v})↾s = μ_{x−E(s)v} + (μ_{x+v})↾s. Proved by Riesz–Markov uniqueness: the test against continuous f reduces, via the polarization + re_inner_cfcHom_specProj + specMeasure_setEngine, to an identity that holds.

MeasurableSets(xv:H),μspTha(x+(EThas)v)+(μspTha(xv)).restrs=μspTha(x(EThas)v)+(μspTha(x+v)).restrs\mathrm{MeasurableSet}\,s \to \forall (x v : H), \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,(x + (\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specproj}{E}\,T\,\mathrm{ha}\,s)\,v) + (\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,(x - v)).\mathrm{restr}\,s = \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,(x - (\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specproj}{E}\,T\,\mathrm{ha}\,s)\,v) + (\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,(x + v)).\mathrm{restr}\,s

Proof. By instIsFiniteMeasureElemRealSpectrumContinuousLinearMapComplexIdSpecMeasure, qForm, bForm, specMeasure_setEngine, re_inner_cfcHom_specProj, integral_specMeasure_polarization. \square

Used by bForm_specProj.

Lemma 743 (bForm_specProj).  source ↗

The intersection identity at the form level: b_t(x, E(s)v) = b_{s∩t}(x, v) (evaluate specProj_engine_measure at t via .real).

MeasurableSetsMeasurableSett(xv:H),bThatx((EThas)v)=bTha(st)xv\mathrm{MeasurableSet}\,s \to \mathrm{MeasurableSet}\,t \to \forall (x v : H), \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-bform}{b}\,T\,\mathrm{ha}\,t\,x\,((\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specproj}{E}\,T\,\mathrm{ha}\,s)\,v) = \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-bform}{b}\,T\,\mathrm{ha}\,(s \cap t)\,x\,v

Proof. By specMeasure, instIsFiniteMeasureElemRealSpectrumContinuousLinearMapComplexIdSpecMeasure, qForm, specProj_engine_measure. \square

Used by specProj_inter.

Lemma 744 (specProj_inter).  source ↗

E_inter: E(s∩t) = E(s)·E(t) — the projection / multiplicativity property, the final ProjectionValuedMeasure field. E(s)·E(t) tested against ⟪·x,y⟫ is c_t(x,E(s)y), which equals c_{s∩t}(x,y) by bForm_specProj (using E(s) ℂ-linear for the imaginary part).

MeasurableSetsMeasurableSettETha(st)=EThasEThat\mathrm{MeasurableSet}\,s \to \mathrm{MeasurableSet}\,t \to \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specproj}{E}\,T\,\mathrm{ha}\,(s \cap t) = \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specproj}{E}\,T\,\mathrm{ha}\,s \cdot \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specproj}{E}\,T\,\mathrm{ha}\,t

Proof. By bForm, cForm, inner_specProj, specProj_isSelfAdjoint, bForm_specProj. \square

Used by PVM_of_selfAdjoint, scalarMeasure_eq_specMeasure.

Definition 745 (PVM_of_selfAdjoint).  source ↗

The bounded spectral theorem (PVM form): every bounded self-adjoint T : H →L[ℂ] H induces a projection-valued measure on spectrum ℝ T, with E(s) = specProj. All structure fields are the lemmas proved above; isIdem is E_inter at s = t.

PVM_of_selfAdjointHT  :=  {E:=ETha,isSA:=,isIdem:=,E_empty:=,E_univ:=,E_inter:=,hasSum_iUnion:=}\mathrm{PVM\_of\_selfAdjoint}\,H\,T \;:=\; \{E :=\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specproj}{E}\,T\,\mathrm{ha} , \mathrm{isSA} :=\cdots , \mathrm{isIdem} :=\cdots , \mathrm{E\_empty} :=\cdots , \mathrm{E\_univ} :=\cdots , \mathrm{E\_inter} :=\cdots , \mathrm{hasSum\_iUnion} :=\cdots \}

Used by rvdSpecMeasure, deviceOpC_norm_le, borelFC_inner_self, rvdSpec_borelFC_diag, rvdSpecMeasure_zero_levelSet, rvdSpecMeasure_two_levelSet, tendsto_integral_devChar_remainder_sq, tendsto_integral_devChar_diff_sq, and 17 more.

Lemma 746 (re_inner_T_eq_integral).  source ↗

Spectral representation of T (diagonal form): ∫_{σ(T)} λ dμ_x(λ) = re ⟪x, T x⟫. Since μ_x is the scalar spectral measure of the PVM_of_selfAdjoint (μ_x(s) = ⟪E(s)x,x⟫), this is the statement T = ∫ λ dE(λ) tested on the diagonal — T recovered from its PVM.

(ω:(spRT)),ωμspThax=re(x,Tx)\int (\omega : (\mathrm{sp}\,\mathbb{R}\,T)), \omega \partial \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-specmeasure}{\mu_{\mathrm{sp}}}\,T\,\mathrm{ha}\,x = \mathrm{re}\,(\langle {x},{T\,x}\rangle)

Proof. By integral_specMeasure. \square

Used by diagInt_specCoord.

Definition 747 (borelFC).  source ↗

The bounded Borel functional calculus of a bounded self-adjoint T: f(T) for bounded measurable f : σ(T) → ℂ.

ΦBHTfC  :=  (PVM_of_selfAdjointTha).ΦhfhC0hC\Phi_{B}\,H\,T\,f\,C \;:=\; (\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-pvm-of-selfadjoint}{\mathrm{PVM\_of\_selfAdjoint}}\,T\,\mathrm{ha}).\Phi\,\mathrm{hf}\,\mathrm{hC0}\,\mathrm{hC}

Used by borelFC_congr_ae, deviceOpC_neg_half_eq, deviceOpReal, deviceOpC, deviceOpC_norm_le, deviceOpReal_zero, deviceOpReal_eq, borelFC_inner_self, and 36 more.

Lemma 748 (inner_borelFC).  source ↗

Defining property: ⟪x, f(T) y⟫ = B_f(x,y) (the polarized scalar-measure form).

x,(ΦBThahfhC0hC)y=(PVM_of_selfAdjointTha).bdfxy\langle {x},{(\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-borelfc}{\Phi_{B}}\,T\,\mathrm{ha}\,\mathrm{hf}\,\mathrm{hC0}\,\mathrm{hC})\,y}\rangle = (\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-pvm-of-selfadjoint}{\mathrm{PVM\_of\_selfAdjoint}}\,T\,\mathrm{ha}).\mathrm{bd}\,f\,x\,y

Proof. By inner_boundedFC. \square

Used by borelFC_inner_self, rvdSpec_borelFC_diag, borelFC_adjoint, rvdRC_eq_borelFC.

Lemma 749 (borelFC_mul).  source ↗

Multiplicativity of the bounded Borel FC: (f·g)(T) = f(T)·g(T).

ΦBThahfphC0phCp=ΦBThahfhC0fhCfΦBThahghC0ghCg\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-borelfc}{\Phi_{B}}\,T\,\mathrm{ha}\,\mathrm{hfp}\,\mathrm{hC0p}\,\mathrm{hCp} = \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-borelfc}{\Phi_{B}}\,T\,\mathrm{ha}\,\mathrm{hf}\,\mathrm{hC0f}\,\mathrm{hCf} \cdot \href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-borelfc}{\Phi_{B}}\,T\,\mathrm{ha}\,\mathrm{hg}\,\mathrm{hC0g}\,\mathrm{hCg}

Proof. By boundedFC_mul, PVM_of_selfAdjoint. \square

Used by deviceOpReal_eq, borelFC_inner_self, deviceOpC_bottomEdge_eq, modUnitary_add, borelFC_comm, cfcCont_mul, cfcΩ_hΩ, rvdRC_mul_E_levelSet.

Lemma 750 (borelFC_one).  source ↗

The bounded Borel FC is unital: (fun _ => 1)(T) = 1.

ΦBTha=1\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-borelfc}{\Phi_{B}}\,T\,\mathrm{ha}\,\cdots \,\cdots \,\cdots = 1

Proof. By boundedFC, boundedFC_const, PVM_of_selfAdjoint. \square

Used by modUnitary_zero, cfcCont_one.

Lemma 751 (borelFC_const).  source ↗

Constant rule (fun _ => c)(T) = c·1 — the QIQTH-layer wrapper of boundedFC_const.

ΦBTha=c1\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-borelfc}{\Phi_{B}}\,T\,\mathrm{ha}\,\cdots \,\cdots \,\cdots = c \cdot 1

Proof. By boundedFC_const, PVM_of_selfAdjoint. \square

Used by rvdRC_mul_E_levelSet.

Lemma 752 (borelFC_indicator).  source ↗

Indicator rule 𝟙_s(T) = E s — the QIQTH-layer wrapper of boundedFC_indicator: the bounded Borel FC of a level-set indicator is the corresponding spectral projection of the PVM.

ΦBTha=(PVM_of_selfAdjointTha).Es\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-borelfc}{\Phi_{B}}\,T\,\mathrm{ha}\,\cdots \,\cdots \,\cdots = (\href{/browser/qiqth-spectral-spectraltheorem#d-qiqth-spectraltheorem-pvm-of-selfadjoint}{\mathrm{PVM\_of\_selfAdjoint}}\,T\,\mathrm{ha}).E\,s

Proof. By boundedFC_indicator. \square

Used by rvdRC_mul_E_levelSet.


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