Alphabeta Math
ExampleConstruction: AI-adaptedVerification: AI-adaptedprecheck pass
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.

Low-lying radial distributions of the Coulomb model: normalisations, moments and the failure of cross-l orthogonality of reduced functions

Physical scope

An exact computation of the reduced radial functions, their normalisations and low moments for the states with n = 1 and n = 2 of the declared one-centre Coulomb model, together with the explicit check that reduced radial functions of different angular momentum are not orthogonal in L^2(dr). The example is a conditional model computation in terms of the declared parameters; it reports no measured radius or density, identifies no size with a laboratory length, and asserts no orbit or trajectory.

Example

Adopt the declared one-centre Coulomb model The declared Coulomb and two-body hydrogen model: one-centre operator, relative problem, reduced mass and scope exclusions clauses (a)-(c) with parameters ℏ>0, m>0, coupling κ>0 and a:=aκ=ℏ2/(mκ), and the radial reading of The one-centre Coulomb model: position and radial distributions of the bound states, with the ground-state density and its scales. In the notation of that item, unl denotes the reduced regular solution with ψnlm(x)=unl(r)Ylm(Ω)/r and pnl=∣unl∣2/∥unl∥22 the radial density of the normalised bound state. For the three reduced solutions below choose the normalisation ∥unl∥2=1 and the phase for which the coefficient cnl multiplying the displayed Laguerre polynomial-exponential expression is positive real. Then:

(a) u10(r)=2a−3/2r e−r/a and u20(r)=2−3/2a−3/2(2r−r2a)e−r/(2a) and u21(r)=2−3/23−1/2a−5/2r2e−r/(2a);

(b) ∥u10∥2=∥u20∥2=∥u21∥2=1, so for these states the reduced solution is already normalised and pnl=∣unl∣2;

(c) the moments ∫0∞r p10(r) dr=3a2,∫0∞r2p10(r) dr=3a2,∫0∞r p20(r) dr=6a,∫0∞r p21(r) dr=5a, and ∫0∞p20(r)r dr=∫0∞p21(r)r dr=14a;

(d) the same-l pair is orthogonal, ∫0∞u10(r)u20(r) dr=0, while the different-l pair is not: ∫0∞u20(r)u21(r) dr=−32≠0, so the reduced radial functions of different angular momentum are not orthogonal in L2((0,∞),dr), the orthogonality of the full bound states being carried by the angular factor;

(e) the closed forms of (a) agree with the standard radial functions Rnl=unl/r of the cited treatments for these states, and the value ∫r pnl for the circular state n=2, l=1 agrees with the general circular-orbit formula ⟨r⟩n,n−1=n(n+12)a at n=2;

(f) Scope. The computation is conditional on the declared model and the cited mathematics; a is a model scale, the moments are moments of the model's radial reading and not measured radii, and no measurement, orbit or trajectory is asserted.

Verification

Given: The declared one-centre Coulomb model with ℏ,m,κ>0, a=ℏ2/(mκ), γ=2/a; the reduced solutions unl of the model with ψnlm=unl(r)Ylm(Ω)/r; the Axiom of Countable Choice.

[L1] Exponential moments. For every λ>0 and integer k≥0, ∫0∞rke−λrdr=k!/λk+1 (Moments of the exponential law on the half-line).

[L2] Reduced solutions. unl(r)=cnlrl+1e−r/(na)Ln−l−1(2l+1)(2r/(na)) with cnl≠0 and Lj(a) the Laguerre polynomial Lj(a)(x)=∑i=0j(−1)i(j+aj−i)xi/i!; for j=0 one has L0(a)=1 and for j=1 one has L1(a)(x)=1+a−x (Kummer recurrence and termination clause (d), The one-centre Coulomb model: position and radial distributions of the bound states, with the ground-state density and its scales clause (c)).

[L3] Radial reading. For a radial set the position law of the normalised bound state is ∫abpnl(r)dr with pnl=∣unl∣2/∥unl∥22, and ∫0∞pnldr=1 (The one-centre Coulomb model: position and radial distributions of the bound states, with the ground-state density and its scales clause (a), Position and momentum outcome laws of the massive spin-s model clause (b)).

Proof technique: direct; insert the Laguerre data into the closed forms, evaluate the resulting elementary integrals with the exponential-moments lemma, and compare with the cited radial functions.

Given: The data of the statement and [L1]-[L3].

1.1givenL2algebra

[Closed forms] For n=1, l=0: j=0, k=1/(na)=1/a, so [L2] gives u10(r)=c re−r/a. For n=2, l=0: j=1, L1(1)(x)=2−x and k=1/(2a), so u20(r)=c re−r/(2a)(2−r/a). For n=2, l=1: j=0, L0(3)=1 and k=1/(2a), so u21(r)=c r2e−r/(2a). The constants c are fixed by the normalisation condition ∥unl∥2=1, evaluated in the next step, giving the displayed coefficients of (a).

2.1step 1.1L1algebra

[Normalisations] By [L1] with λ=2/a: ∫0∞r2e−2r/adr=2/(2/a)3=a3/4 and ∫0∞r4e−2r/adr=24/(2/a)5=3a5/4; hence ∫0∞(2a−3/2re−r/a)2dr=4a−3⋅a3/4=1, so c=2a−3/2 for u10 and ∥u10∥2=1. By [L1] with λ=1/a: ∫0∞r2e−r/adr=2a3, ∫0∞r3e−r/adr=6a4, ∫0∞r4e−r/adr=24a5; expanding (2−r/a)2=4−4r/a+r2/a2 gives ∫0∞r2(2−r/a)2e−r/adr=8a3−24a3+24a3=8a3, so c=2−3/2a−3/2 yields ∥u20∥2=1; and c2∫r4e−r/adr=c2⋅24a5=1 gives c=24−1/2a−5/2=2−3/23−1/2a−5/2 for u21. This is (b).

2.2step 1.1L1algebra

[Moments of the ground state] With p10=4a−3r2e−2r/a, [L1] gives ∫0∞r p10(r)dr=4a−3⋅3!/(2/a)4=4a−3⋅6a4/16=3a/2 and ∫0∞r2p10(r)dr=4a−3⋅4!/(2/a)5=4a−3⋅24a5/32=3a2. Thus the variance is 3a2−(3a/2)2=3a2/4.

2.3step 1.1L1algebra

[Moments of the n=2 states] With p20=2−3a−3r2(2−r/a)2e−r/a and p21=24−1a−5r4e−r/a, [L1] gives ∫r p20=2−3a−3∫r3(2−r/a)2e−r/adr=2−3a−3⋅a4∫x3(4−4x+x2)e−xdx=2−3a−3⋅a4(4⋅3!−4⋅4!+5!)=2−3a−3⋅48a4=6a; and ∫r p21=24−1a−5⋅5!a6=5a. Moreover ∫r−1p20=2−3a−3∫r(2−r/a)2e−r/adr=2−3a−3(4⋅1! a2−4⋅2! a2+3! a2)=2−3a−3⋅2a2=a−1/4, and ∫r−1p21=24−1a−5⋅3!a4=a−1/4. This is (c).

2.4step 1.1L1algebra

[Overlaps] With u10=2a−3/2re−r/a and u20=2−3/2a−3/2(2r−r2/a)e−r/(2a) one has ∫u10u20dr=2−1/2a−3∫(2r2−r3/a)e−3r/(2a)dr; by [L1] with λ=3/(2a), ∫r2e−3r/(2a)dr=2(2a/3)3=16a3/27 and ∫r3e−3r/(2a)dr=6(2a/3)4=32a4/27, so the bracket is 2⋅16a3/27−(32a4/27)/a=0: the same-l pair is orthogonal. With u21=2−3/23−1/2a−5/2r2e−r/(2a), the cross overlap is ∫u20u21dr=2−33−1/2a−4∫(2r3−r4/a)e−r/adr=2−33−1/2a−4(2⋅6a4−24a4)=2−33−1/2(−12)=−3/(23)=−3/2, nonzero. This is (d).

3.1step 1.1step 2.3L1L2L3∎

[Cross-checks and scope] Since Rnl=unl/r, step 1.1 gives R10=2a−3/2e−r/a, R20=2−3/2a−3/2(2−r/a)e−r/(2a) and R21=2−3/23−1/2a−3/2(r/a)e−r/(2a), which agree with the cited tabulated radial functions, and the value 5a of step 2.3 agrees with the circular-orbit formula ⟨r⟩n,n−1=n(n+12)a at n=2; this is (e). Only the declared model, the cited mathematics and the exponential-moments lemma were used, and a remains a model scale, so the scope statement (f) holds.

Remarks

  • Why cross-l overlaps need not vanish. The full bound states ψnlm and ψn′l′m′ are orthogonal in L2(R3) whenever the angular factors Ylm,Yl′m′ are orthogonal, even if the reduced radial functions overlap; the nonzero value −3/2 computed in (d) is exactly such a case. No orthogonality of reduced functions across angular momenta is claimed anywhere on this pair.
  • Moments are readings, not measurements. The mean radius and the inverse radius are moments of the model's radial reading; the inverse-radius value 1/(4a) for the two n=2 states is a consistency check with the model's virial-type relation and is not compared with any measured quantity here.

Depends on

Dependency tree · 2 levels

Sources