Alphabeta Math
ExampleConstruction: AI-adaptedVerification: AI-generatedprecheck 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.

An exact observer-relative energy and momentum computation at relative speed c/2, with the expansion bounds of the low-velocity lemma checked by exact rational comparison

Example

Work on the flat model of The flat model spacetime: the Minkowski metric on R^4 and its inertial chart with inertial chart x and let c>0 and m>0. At p with x(p)=0 take the observer n:=∂0∣p and the tangent vector

P:=mc u,u:=23 ∂0∣p+13 ∂1∣p,

so that gp(u,u)=−1 and P is future timelike with rest mass m (Observer-relative energy, spatial momentum and rest mass of a tangent vector). Then the observer data of the low-velocity lemma are

hn(u)=13 ∂1∣p,γ=23,w=c2 ∂1∣p,s=c2,

and the exact energy and momentum are

En(P)=2mc23,qn(P)=mc3 ∂1∣p,∣qn(P)∣=mc3.

With v0:=c/2, z0=1/4 this realizes s=v0<c and the exact identities

En(P)=mc2(1−s2c2)−1/2,∣qn(P)∣=ms(1−s2c2)−1/2

of Low-velocity expansions of observer energy and momentum with uniform error bounds, and the two uniform error bounds of that lemma read

∣En(P)−mc2−12ms2∣=mc2(16−93)83≤mc2123,∣∣qn(P)∣−ms∣=mc(2−3)23≤mc63,

which are strict, finite checks of the bounds at the single relative speed s=c/2.

Facts & Assumptions

Given: The flat model with inertial chart x, the point p with x(p)=0, the observer n=∂0∣p, the vector u=23∂0∣p+13∂1∣p, and P=mc u with c,m>0.

[L1]

An observer at p is a future-directed vector n with gp(n,n)=−1; the spatial projection is hn(v)=v+gp(n,v)n (Observers, rest spaces and the spatial projection at an event clauses (a) and (c)). The projections satisfy hn(n)=0, hn(v)=v for gp(v,n)=0, and gp(hn(v),hn(v))=gp(v,v)+gp(v,n)2 (The observer rest-space decomposition and the spatial projection clauses 1-2).

[L2]

For P future timelike with rest mass m>0, U=P/m, u=U/c, γ=−gp(n,u): γ≥1, En(P)=mc2γ, qn(P)=mγw, gp(qn,qn)=m2c2(γ2−1) with w=c hn(u)/γ, and En(P)=−cgp(P,n), qn(P)=hn(P) (Observer-relative energy, spatial momentum and rest mass of a tangent vector clauses (a)-(b), Positivity, relative-velocity identities and the mass shell of observer-relative energy and momentum clause 3).

[L3]

With s:=gp(w,w): s<c, γ=(1−s2/c2)−1/2, En(P)=mc2(1−s2/c2)−1/2, ∣qn(P)∣=ms(1−s2/c2)−1/2, and for every 0≤v0<c with z0=v02/c2<1 and all s≤v0 the two error bounds of the statement of Low-velocity expansions of observer energy and momentum with uniform error bounds hold.

[L4]

In the inertial chart gab=ηab=diag⁡(−1,1,1,1); η(∂0,∂0)=−1 and gp(∂1,∂1)=1 (The flat model spacetime: the Minkowski metric on R^4 and its inertial chart, Timelike, null, spacelike and causal vectors of a Lorentz vector space).

[L5]

Arithmetic: 3 is the positive root of 3 (Rational powers ar of a positive base) and 53<3<2, since 259<3<4. Hence 23=233, 13=33, 13−12=2−323>0, 93<16 since (93)2=243<256=162, and 273>46 since (273)2=2187>2116=462, both by squaring positive quantities; hence 16−9383>0.

Verification

technique · direct; evaluate the observer data and the mass-shell identities on the explicit vector $u$, then verify the two expansion bounds by exact algebraic comparison
1.1L1L2L4algebra

(Observer data.) By [L4], gp(n,n)=−1, so n is a unit future-directed timelike vector, i.e. an observer. Set u as given; then gp(u,u)=43gp(∂0,∂0)+13gp(∂1,∂1)=−43+13=−1, so u is future timelike with gp(u,u)=−1, and P=mcu is future timelike with rest mass m(P)=m by [L2]. Further gp(n,u)=−23, so by [L1] hn(u)=u+gp(n,u)n=23∂0+13∂1−23∂0=13∂1. Hence γ=−gp(n,u)=23≥1, w=c hn(u)/γ=c2∂1, and s=gp(w,w)=c2 by [L4].

2.1step 1.1L1L2L4algebra

(Exact energy and momentum.) By [L2] and [L4]: En(P)=−cgp(P,n)=−mc2 gp(u,∂0)=mc2⋅23 and qn(P)=hn(P)=mc hn(u)=mc3∂1, so ∣qn(P)∣=gp(qn,qn)=mc3 since gp(∂1,∂1)=1.

3.1step 1.1step 2.1L3L5algebra

(Exact identities at s=c/2.) By step 1.1, s=c/2<c and 1−s2/c2=3/4, so (1−s2/c2)−1/2=2/3; step 2.1 gives En(P)=mc2⋅23=mc2(1−s2/c2)−1/2 and ∣qn(P)∣=mc3=m⋅c2⋅23=ms(1−s2/c2)−1/2, which are the exact identities of [L3].

4.1step 3.1L3L5algebra

(Energy bound.) By step 3.1, ∣En(P)−mc2−12ms2∣=mc2∣23−1−18∣=mc2(23−98)=mc2 16−9383, the sign being positive by [L5]. The bound of [L3] at v0=c/2 is 38(34)−5/2m(c/2)4c2=38⋅3293⋅mc216=mc2123 using (43)5/2=169⋅23 and 3>0. The inequality 16−9383≤1123 is equivalent, upon multiplying by the positive 243, to 3(16−93)≤2, i.e. 273≥46, which holds by [L5].

5.1step 3.1step 4.1L3L5algebra∎

(Momentum bound.) By step 3.1, ∣∣qn(P)∣−ms∣=mc∣13−12∣=mc(13−12)=mc 2−323 by [L5]. The bound of [L3] at v0=c/2 is 12(34)−3/2m(c/2)3c2=12⋅833⋅mc8=mc63 using (43)3/2=43⋅23. The inequality 2−323≤163 is equivalent, upon multiplying by the positive 63, to 3(2−3)≤1, i.e. 33≥5, which holds since 27>25 and both sides are positive. Both bounds of the lemma are therefore satisfied strictly at the relative speed s=c/2, and the exact identities of step 3.1 verify its statements s<c, γ=(1−s2/c2)−1/2 and the two displayed formulas.

  • Scope. The example is a finite algebraic check of the kinematic identities and error bounds at one relative speed; it involves no dynamics, no conservation law and no measurement. The choices s=c/2 and the direction ∂1 are arbitrary normalizations; the points checked are the exact identities and the two strict inequalities.

Depends on

Dependency tree · 2 levels

Sources