"The Schwarzschild radius of the Sun calculated via rs = 2GM/c² with 2022 CODATA values for G, solar mass, and c lies strictly between 2.95 km and 2.96 km."

physics mathematics · generated 2026-04-06 · v1.7.0
PROVED 4 citations
All sub-claims confirmed with 4 verified citations and no disconfirming evidence found.
Verified by Proof Engine — an open-source tool that verifies claims using cited sources and executable code. Reasoning transparent and auditable.
methodology · github · re-run this proof · submit your own

The Sun's Schwarzschild radius — the size it would need to be compressed to in order to become a black hole — comes out to 2.953 km, firmly inside the claimed range.

What Was Claimed?

If you could somehow squeeze all of the Sun's mass into a sphere smaller than about 3 kilometers across, it would collapse into a black hole. The specific claim here is that when you compute this critical radius using the standard formula and the best available physical constants, the result falls strictly between 2.95 km and 2.96 km — not approximately, but precisely within that narrow 10-meter window.

This matters because the Schwarzschild radius is a foundational result in general relativity, and pinning it down to a specific numerical range requires using authoritative values for the gravitational constant, the speed of light, and the Sun's mass.

What Did We Find?

The calculation centers on the formula rs = 2GM/c², where G is Newton's gravitational constant, M is the Sun's mass, and c is the speed of light. Using the 2022 CODATA recommended values from NIST — the international reference standard for physical constants — and the IAU 2015 nominal solar mass parameter, the result is 2.953250 km.

That single number settles the claim: 2.953250 is greater than 2.95 and less than 2.96, so both strict inequalities hold.

One subtle detail is worth noting. CODATA doesn't actually publish a standalone solar mass value. Instead, astronomers work with the gravitational parameter GM☉ — the product of G and the solar mass — which is measured far more precisely than either quantity alone. Using this combined value directly, G cancels out of the formula entirely, and the result is unchanged: 2.953250 km.

Two independent calculation paths were run: one decomposing the gravitational parameter into G and M separately, then recombining; the other using the gravitational parameter directly. Both returned identical results to ten significant figures. A third calculation using an independently published value from Wikipedia's solar mass article — a slightly more precise figure — agreed to within 50 nanometers of the primary result.

What Should You Keep In Mind?

The 10-meter window between 2.95 and 2.96 km is narrow, but the computed value of 2.9533 km sits comfortably near the middle, about 3 meters above the lower bound and 7 meters below the upper bound. The uncertainty in G, the least precisely known of the constants, can only shift the result by about 0.06 meters — a factor of 50 too small to threaten the claim.

Different time coordinate conventions used in astronomy (TCB, TDB, TCG) produce slightly different versions of the solar gravitational parameter. The differences appear only in the eighth significant digit, shifting the Schwarzschild radius by less than a millimeter. This has no effect on the result.

Popular sources like Wikipedia and NASA round the Sun's Schwarzschild radius to "approximately 3 km." That rounding is correct but hides the precision the claim is asserting. No authoritative source places the value outside the range 2.9–3.0 km, and all precise computations agree near 2.953 km.

How Was This Verified?

This was verified by fetching the relevant physical constants live from NIST and IAU sources, running two independent calculations, and cross-checking against a third independently published value. See the structured proof report for the full evidence summary and proof logic, the full verification audit for source credibility, extraction records, and adversarial checks, or re-run the proof yourself to reproduce the computation from scratch.

What could challenge this verdict?

Sources

SourceIDTypeVerified
NIST 2022 CODATA Recommended Values B1 Government Yes
NIST 2022 CODATA Recommended Values B2 Government Yes
IAU 2015 Resolution B3 (Mamajek et al. 2015, arXiv:1510.07674) B3 Academic Yes
Wikipedia — Solar mass (TCG-compatible GM☉ estimate) B4 Reference Yes
rs via separate G and M (primary) A1 Computed
rs via GM☉ directly (cross-check) A2 Computed

detailed evidence

Detailed Evidence

Evidence Summary

ID Fact Verified
B1 Newtonian gravitational constant G (2022 CODATA) Yes
B2 Speed of light c (2022 CODATA, exact) Yes
B3 Nominal solar mass parameter GM☉^N (IAU 2015 Resolution B3) Yes
B4 Solar mass cross-check (Wikipedia) Yes
A1 rs via separate G and M (primary) Computed: 2.953250 km
A2 rs via GM☉ directly (cross-check) Computed: 2.953250 km

Proof Logic

The Schwarzschild radius is defined by rs = 2GM/c², where G is the gravitational constant, M is the mass of the object, and c is the speed of light.

Constants used: - G = 6.67430 × 10⁻¹¹ m³ kg⁻¹ s⁻² (B1, 2022 CODATA) - c = 299 792 458 m s⁻¹ (B2, 2022 CODATA, exact by definition) - GM☉^N = 1.3271244 × 10²⁰ m³ s⁻² (B3, IAU 2015 Resolution B3 nominal value)

Primary computation (A1): Derive M☉ = GM☉^N / G = 1.988410 × 10³⁰ kg, then compute rs = 2GM☉/c² = 2953.250 m = 2.953250 km.

Cross-check (A2): Compute rs = 2(GM☉^N)/c² directly, bypassing the G decomposition. Result: 2.953250 km — identical to A1 (G cancels algebraically).

Independent source cross-check: Using the Wikipedia TCG-compatible GM☉ = 1.32712442099 × 10²⁰ m³ s⁻² (B4), rs = 2.953250 km, agreeing within 5 × 10⁻⁸ km.

Since 2.95 < 2.953250 < 2.96, both strict inequalities hold.

Conclusion

PROVED. The Schwarzschild radius of the Sun, computed as rs = 2GM/c² = 2.953250 km, lies strictly between 2.95 km and 2.96 km. All four sources are fully verified: NIST CODATA for G and c, IAU 2015 Resolution B3 for GM☉, and the Wikipedia cross-check for GM☉ (TCG-compatible).

audit trail

Citation Verification 4/4 verified

All 4 citations verified.

Original audit log

B1: Newtonian gravitational constant G

  • Status: verified
  • Method: full_quote
  • Fetch mode: live

B2: Speed of light c

  • Status: verified
  • Method: full_quote
  • Fetch mode: live

B3: Nominal solar mass parameter GM☉^N

  • Status: verified
  • Method: full_quote
  • Fetch mode: live

B4: Solar mass cross-check (Wikipedia)

  • Status: verified
  • Method: full_quote
  • Fetch mode: live

Source: proof.py JSON summary

Claim Specification
Field Value
Subject Schwarzschild radius of the Sun
Property rs = 2GM/c² in kilometres
Operator compound: > AND <
Threshold (lower) 2.95
Threshold (upper) 2.96
Operator note "strictly between" means rs > 2.95 AND rs < 2.96 (both strict). CODATA does not publish solar mass; IAU 2015 Resolution B3 nominal GM☉^N is used instead, with M☉ derived as GM☉^N / G.

Source: proof.py JSON summary

Claim Interpretation

Claim: "The Schwarzschild radius of the Sun calculated via rs = 2GM/c² with 2022 CODATA values for G, solar mass, and c lies strictly between 2.95 km and 2.96 km."

Formal interpretation: rs > 2.95 km AND rs < 2.96 km (both strict). If rs were exactly 2.95 or 2.96, the claim would be false.

Source substitution: CODATA does not publish a solar mass value. The standard approach uses the IAU 2015 Resolution B3 nominal solar mass parameter GM☉^N = 1.3271244 × 10²⁰ m³ s⁻² and derives M☉ = GM☉^N / G. Since rs = 2GM/c² = 2(GM☉^N)/c², the value of G cancels in the computation, but both paths are computed for cross-checking.

Source Credibility Assessment
Fact ID Domain Type Tier Note
B1 nist.gov government 5 Government domain (.gov)
B2 nist.gov government 5 Government domain (.gov)
B3 arxiv.org academic 4 Known academic/scholarly publisher
B4 wikipedia.org reference 3 Established reference source

All sources are tier 3 or above. No flags.

Source: proof.py JSON summary

Computation Traces
Solar mass M☉ = GM☉^N / G: GM_sun_iau / G = 1.3271244e+20 / 6.6743e-11 = 1.99e+30
  M☉ = 1.988410e+30 kg
rs = 2GM/c² (primary, metres): 2 * G * M_sun / (c ** 2) = 2 * 6.6743e-11 * 1.988409870698051e+30 / 299792458.0 ** 2 = 2953.2501
rs in kilometres (primary): rs_primary_m / 1000 = 2953.2500761002498 / 1000 = 2.9533
rs = 2(GM☉)/c² (direct, metres): 2 * GM_sun_iau / (c ** 2) = 2 * 1.3271244e+20 / 299792458.0 ** 2 = 2953.2501
rs in kilometres (cross-check): rs_crosscheck_m / 1000 = 2953.2500761002498 / 1000 = 2.9533
rs primary vs direct (km): 2.95325007610025 vs 2.95325007610025, diff=0.0, tolerance=1e-10 -> AGREE
rs using Wikipedia GM☉ (metres): 2 * GM_sun_wiki / (c ** 2) = 2 * 1.32712442099e+20 / 299792458.0 ** 2 = 2953.2501
rs using Wikipedia GM☉ (km): rs_wiki_m / 1000 = 2953.250122809299 / 1000 = 2.9533
rs IAU vs Wikipedia (km): 2.95325007610025 vs 2.953250122809299, diff=4.670904907300155e-08, tolerance=1e-05 -> AGREE
rs > 2.95 km: 2.95325007610025 > 2.95 = True
rs < 2.96 km: 2.95325007610025 < 2.96 = True

Source: proof.py inline output (execution trace)

Independent Source Agreement
Cross-check Values Agreement Tolerance
GM☉ IAU nominal vs Wikipedia TCG 1.3271244e+20 vs 1.32712442099e+20 AGREE 1e-5 relative
rs primary (G×M) vs direct (GM☉/c²) 2.9532500761 vs 2.9532500761 AGREE 1e-10 km absolute
rs IAU nominal GM☉ vs Wikipedia GM☉ 2.953250 vs 2.953250 AGREE 1e-5 km absolute

Note: The primary computation decomposes GM☉ into G and M (M = GM☉/G), then recombines as 2GM/c². The cross-check uses GM☉ directly. In exact arithmetic these are identical; in floating point they agree to machine precision (diff = 0). The Wikipedia cross-check uses an independently published GM☉ value with more significant digits, providing a genuinely independent data source. Both upstream GM☉ values (IAU nominal and measured TCG) are independently published — same upstream measurement tradition but different compilation and rounding.

Source: proof.py JSON summary

Adversarial Checks

1. Could uncertainty in G shift rs outside [2.95, 2.96] km?

  • Verification performed: Computed rs using G ± uncertainty (6.67430 ± 0.00015 × 10⁻¹¹). Since rs = 2(GM☉)/c² and G cancels when using the GM☉ product, G's uncertainty does not affect the result. Even computing via G×M separately, the relative uncertainty in G (2.2 × 10⁻⁵) shifts rs by only ~0.00006 km, well within the 0.01 km band.
  • Finding: G uncertainty cannot move rs outside [2.95, 2.96].
  • Breaks proof: No

2. Does the choice of time coordinate (TCB vs TDB) for GM☉ matter?

  • Verification performed: Searched for TCB vs TDB solar mass parameter values. TCG: 1.32712442099 × 10²⁰, TDB: 1.32712440041 × 10²⁰. IAU nominal: 1.3271244 × 10²⁰. Difference is in the 8th digit, yielding ~10⁻⁸ relative change in rs — negligible.
  • Finding: Time coordinate choice shifts rs by < 10⁻⁵ km. No impact.
  • Breaks proof: No

3. Do any authoritative sources cite a Schwarzschild radius outside [2.95, 2.96] km?

  • Verification performed: Searched web: 'Schwarzschild radius Sun km value'. Wikipedia cites 'approximately 3.0 km' and '2.95 × 10³ m'. NASA SpaceMath cites ~3 km. No source gives a value outside the range [2.9, 3.0] km, and all precise computations give ~2.953 km.
  • Finding: No authoritative source contradicts the [2.95, 2.96] range.
  • Breaks proof: No

Source: proof.py JSON summary

Quality Checks
  • Rule 1: Values extracted from data_values strings, not hand-typed
  • Rule 2: All 4 citations fetched live; all 4 verified (full_quote)
  • Rule 3: N/A — no date-dependent logic in this proof
  • Rule 4: CLAIM_FORMAL with operator_note documents the compound operator choice and source substitution for solar mass
  • Rule 5: Three adversarial checks searched for independent counter-evidence (G uncertainty, time coordinate, external sources)
  • Rule 6: Four independent sources (2 NIST, 1 IAU/arXiv, 1 Wikipedia); two independent computation paths (G×M vs GM☉ direct)
  • Rule 7: All computations use explain_calc(), compare(), and cross_check() from computations.py
  • validate_proof.py result: PASS with 1 warning (compound claim_holds uses and of two compare() calls — appropriate for two-sided bound)

Source: author analysis

Source Data
Fact ID Extracted Value Source String Value in Quote
B1_G 6.6743e-11 6.674 30 x 10^-11 Yes
B2_c 299792458.0 299 792 458 Yes
B3_GM_sun 1.3271244e+20 1.3271244 x 10^20 Yes
B4_GM_sun_tcg 1.32712442099e+20 1.32712442099 x 10^20 Yes

Extraction method: Values parsed from data_values strings which are formatted as they appear on the source pages. Space-separated digit groups (NIST convention) are joined before parsing to float. Exponents are applied programmatically. Source: author analysis

Source: proof.py JSON summary

Cite this proof
Proof Engine. (2026). Claim Verification: “The Schwarzschild radius of the Sun calculated via rs = 2GM/c² with 2022 CODATA values for G, solar mass, and c lies strictly between 2.95 km and 2.96 km.” — Proved. https://proofengine.info/proofs/the-schwarzschild-radius-of-the-sun-calculated-via/
Proof Engine. "Claim Verification: “The Schwarzschild radius of the Sun calculated via rs = 2GM/c² with 2022 CODATA values for G, solar mass, and c lies strictly between 2.95 km and 2.96 km.” — Proved." 2026. https://proofengine.info/proofs/the-schwarzschild-radius-of-the-sun-calculated-via/.
@misc{proofengine_the_schwarzschild_radius_of_the_sun_calculated_via,
  title   = {Claim Verification: “The Schwarzschild radius of the Sun calculated via rs = 2GM/c² with 2022 CODATA values for G, solar mass, and c lies strictly between 2.95 km and 2.96 km.” — Proved},
  author  = {{Proof Engine}},
  year    = {2026},
  url     = {https://proofengine.info/proofs/the-schwarzschild-radius-of-the-sun-calculated-via/},
  note    = {Verdict: PROVED. Generated by proof-engine v1.7.0},
}
TY  - DATA
TI  - Claim Verification: “The Schwarzschild radius of the Sun calculated via rs = 2GM/c² with 2022 CODATA values for G, solar mass, and c lies strictly between 2.95 km and 2.96 km.” — Proved
AU  - Proof Engine
PY  - 2026
UR  - https://proofengine.info/proofs/the-schwarzschild-radius-of-the-sun-calculated-via/
N1  - Verdict: PROVED. Generated by proof-engine v1.7.0
ER  -
View proof source 357 lines · 15.2 KB

This is the proof.py that produced the verdict above. Every fact traces to code below. (This proof has not yet been minted to Zenodo; the source here is the working copy from this repository.)

"""
Proof: The Schwarzschild radius of the Sun calculated via rs = 2GM/c²
with 2022 CODATA values for G, solar mass, and c lies strictly between
2.95 km and 2.96 km.
Generated: 2026-03-28
"""
import json
import os
import sys

PROOF_ENGINE_ROOT = os.environ.get("PROOF_ENGINE_ROOT")
if not PROOF_ENGINE_ROOT:
    _d = os.path.dirname(os.path.abspath(__file__))
    while _d != os.path.dirname(_d):
        if os.path.isdir(os.path.join(_d, "proof-engine", "skills", "proof-engine", "scripts")):
            PROOF_ENGINE_ROOT = os.path.join(_d, "proof-engine", "skills", "proof-engine")
            break
        _d = os.path.dirname(_d)
    if not PROOF_ENGINE_ROOT:
        raise RuntimeError("PROOF_ENGINE_ROOT not set and skill dir not found via walk-up from proof.py")
sys.path.insert(0, PROOF_ENGINE_ROOT)
from datetime import date

# --- STRUCTURAL IMPORTS ---
from scripts.verify_citations import verify_all_citations, build_citation_detail, verify_data_values
from scripts.computations import compare, explain_calc, cross_check

# ============================================================================
# 1. CLAIM INTERPRETATION (Rule 4)
# ============================================================================
CLAIM_NATURAL = (
    "The Schwarzschild radius of the Sun calculated via rs = 2GM/c² "
    "with 2022 CODATA values for G, solar mass, and c lies strictly "
    "between 2.95 km and 2.96 km."
)
CLAIM_FORMAL = {
    "subject": "Schwarzschild radius of the Sun",
    "property": "rs = 2GM/c² in kilometres",
    "operator": "compound: > AND <",
    "operator_note": (
        "'strictly between 2.95 km and 2.96 km' means rs > 2.95 AND rs < 2.96 "
        "(both strict inequalities). If rs were exactly 2.95 or exactly 2.96, "
        "the claim would be FALSE. "
        "CODATA does not publish a solar mass value directly. The standard "
        "approach is to use the IAU 2015 Resolution B3 nominal solar mass "
        "parameter GM☉^N = 1.3271244 × 10²⁰ m³ s⁻² and derive "
        "M☉ = GM☉^N / G. Since rs = 2GM/c² = 2(GM☉^N)/c², the value of G "
        "cancels, but we compute both ways for cross-checking."
    ),
    "threshold_lower": 2.95,
    "threshold_upper": 2.96,
}

# ============================================================================
# 2. FACT REGISTRY
# ============================================================================
FACT_REGISTRY = {
    "B1": {"key": "nist_G", "label": "Newtonian gravitational constant G (2022 CODATA)"},
    "B2": {"key": "nist_c", "label": "Speed of light c (2022 CODATA, exact)"},
    "B3": {"key": "iau_GM_sun", "label": "Nominal solar mass parameter GM☉^N (IAU 2015 Resolution B3)"},
    "B4": {"key": "wiki_solar_mass", "label": "Solar mass cross-check (Wikipedia)"},
    "A1": {"label": "rs via separate G and M (primary)", "method": None, "result": None},
    "A2": {"label": "rs via GM☉ directly (cross-check)", "method": None, "result": None},
}

# ============================================================================
# 3. EMPIRICAL FACTS
# ============================================================================
empirical_facts = {
    "nist_G": {
        "quote": "Newtonian constant of gravitation",
        "url": "https://physics.nist.gov/cgi-bin/cuu/Value?bg",
        "source_name": "NIST 2022 CODATA Recommended Values",
        "data_values": {"G_mantissa": "6.674 30", "G_exponent": "-11"},
    },
    "nist_c": {
        "quote": "speed of light in vacuum",
        "url": "https://physics.nist.gov/cgi-bin/cuu/Value?c",
        "source_name": "NIST 2022 CODATA Recommended Values",
        "data_values": {"c_value": "299 792 458"},
    },
    "iau_GM_sun": {
        "quote": "nominal solar mass parameter",
        "url": "https://ar5iv.labs.arxiv.org/html/1510.07674",
        "source_name": "IAU 2015 Resolution B3 (Mamajek et al. 2015, arXiv:1510.07674)",
        "data_values": {"GM_sun": "1.3271244"},
    },
    "wiki_solar_mass": {
        "quote": "1.32712442099",
        "url": "https://en.wikipedia.org/wiki/Solar_mass",
        "source_name": "Wikipedia — Solar mass (TCG-compatible GM☉ estimate)",
        "data_values": {"GM_sun_tcg": "1.32712442099"},
    },
}

# ============================================================================
# 4. CITATION VERIFICATION (Rule 2)
# ============================================================================
print("=== CITATION VERIFICATION ===")
citation_results = verify_all_citations(empirical_facts, wayback_fallback=True)
for k, v in citation_results.items():
    print(f"  {k}: {v['status']}")

# ============================================================================
# 5. DATA VALUE VERIFICATION
# ============================================================================
print("\n=== DATA VALUE VERIFICATION ===")
dv_nist_G = verify_data_values(
    empirical_facts["nist_G"]["url"],
    empirical_facts["nist_G"]["data_values"],
    "B1",
)
dv_nist_c = verify_data_values(
    empirical_facts["nist_c"]["url"],
    empirical_facts["nist_c"]["data_values"],
    "B2",
)
dv_iau = verify_data_values(
    empirical_facts["iau_GM_sun"]["url"],
    empirical_facts["iau_GM_sun"]["data_values"],
    "B3",
)
dv_wiki = verify_data_values(
    empirical_facts["wiki_solar_mass"]["url"],
    empirical_facts["wiki_solar_mass"]["data_values"],
    "B4",
)

# ============================================================================
# 6. VALUE EXTRACTION (Rule 1)
# ============================================================================
print("\n=== VALUE EXTRACTION ===")

# Extract G: mantissa with spaces + exponent, as published on NIST page
G_mantissa_str = empirical_facts["nist_G"]["data_values"]["G_mantissa"]
G_exponent_str = empirical_facts["nist_G"]["data_values"]["G_exponent"]
G = float(G_mantissa_str.replace(" ", "")) * 10 ** int(G_exponent_str)
print(f"  G = {G_mantissa_str} × 10^{G_exponent_str} = {G} m³ kg⁻¹ s⁻²")

# Extract c: value with spaces as published on NIST page
c_str = empirical_facts["nist_c"]["data_values"]["c_value"]
c = float(c_str.replace(" ", ""))
print(f"  c = {c_str} = {c} m/s")

# Extract GM☉^N: mantissa from IAU page (× 10²⁰)
GM_mantissa_str = empirical_facts["iau_GM_sun"]["data_values"]["GM_sun"]
GM_sun_iau = float(GM_mantissa_str) * 1e20
print(f"  GM☉^N (IAU nominal) = {GM_mantissa_str} × 10²⁰ = {GM_sun_iau} m³ s⁻²")

# Extract GM☉ from Wikipedia (TCG-compatible, for cross-check, × 10²⁰)
GM_wiki_str = empirical_facts["wiki_solar_mass"]["data_values"]["GM_sun_tcg"]
GM_sun_wiki = float(GM_wiki_str) * 1e20
print(f"  GM☉ (Wikipedia TCG) = {GM_wiki_str} × 10²⁰ = {GM_sun_wiki} m³ s⁻²")

# ============================================================================
# 7. CROSS-CHECK: GM☉ values from independent sources (Rule 6)
# ============================================================================
print("\n=== CROSS-CHECK: GM☉ SOURCES ===")
# IAU nominal has 8 sig figs; TCG estimate has 12. They should agree to ~1e-7 relative.
cross_check(GM_sun_iau, GM_sun_wiki, tolerance=1e-5, mode="relative",
            label="GM☉ IAU nominal vs Wikipedia TCG")

# ============================================================================
# 8. COMPUTATION (Rule 7)
# ============================================================================
print("\n=== PRIMARY COMPUTATION ===")
# Primary: Use G and M separately, where M = GM☉^N / G
M_sun = explain_calc("GM_sun_iau / G", locals(), label="Solar mass M☉ = GM☉^N / G")
print(f"  M☉ = {M_sun:.6e} kg")

rs_primary_m = explain_calc("2 * G * M_sun / (c ** 2)", locals(),
                             label="rs = 2GM/c² (primary, metres)")
rs_primary_km = explain_calc("rs_primary_m / 1000", locals(),
                              label="rs in kilometres (primary)")

print("\n=== CROSS-CHECK COMPUTATION ===")
# Cross-check: Use GM☉ directly (G cancels)
rs_crosscheck_m = explain_calc("2 * GM_sun_iau / (c ** 2)", locals(),
                                label="rs = 2(GM☉)/c² (direct, metres)")
rs_crosscheck_km = explain_calc("rs_crosscheck_m / 1000", locals(),
                                 label="rs in kilometres (cross-check)")

print("\n=== CROSS-CHECK: primary vs direct ===")
cross_check(rs_primary_km, rs_crosscheck_km, tolerance=1e-10, mode="absolute",
            label="rs primary vs direct (km)")

# Additional cross-check using Wikipedia GM☉ value
rs_wiki_m = explain_calc("2 * GM_sun_wiki / (c ** 2)", locals(),
                          label="rs using Wikipedia GM☉ (metres)")
rs_wiki_km = explain_calc("rs_wiki_m / 1000", locals(),
                           label="rs using Wikipedia GM☉ (km)")

print("\n=== CROSS-CHECK: IAU nominal vs Wikipedia GM☉ ===")
cross_check(rs_crosscheck_km, rs_wiki_km, tolerance=1e-5, mode="absolute",
            label="rs IAU vs Wikipedia (km)")

# ============================================================================
# 9. CLAIM EVALUATION
# ============================================================================
print("\n=== CLAIM EVALUATION ===")
lower_holds = compare(rs_primary_km, ">", CLAIM_FORMAL["threshold_lower"],
                       label="rs > 2.95 km")
upper_holds = compare(rs_primary_km, "<", CLAIM_FORMAL["threshold_upper"],
                       label="rs < 2.96 km")
claim_holds = lower_holds and upper_holds
print(f"  Both conditions hold: {claim_holds}")

# ============================================================================
# 10. ADVERSARIAL CHECKS (Rule 5)
# ============================================================================
adversarial_checks = [
    {
        "question": "Could uncertainty in G shift rs outside [2.95, 2.96] km?",
        "verification_performed": (
            "Computed rs using G ± uncertainty (6.67430 ± 0.00015 × 10⁻¹¹). "
            "Since rs = 2(GM☉)/c² and G cancels when using the GM☉ product, "
            "G's uncertainty does not affect the result. Even computing via "
            "G×M separately, the relative uncertainty in G (2.2 × 10⁻⁵) shifts "
            "rs by only ~0.00006 km, well within the 0.01 km band."
        ),
        "finding": "G uncertainty cannot move rs outside [2.95, 2.96].",
        "breaks_proof": False,
    },
    {
        "question": "Does the choice of time coordinate (TCB vs TDB) for GM☉ matter?",
        "verification_performed": (
            "Searched for TCB vs TDB solar mass parameter values. "
            "TCG: 1.32712442099 × 10²⁰, TDB: 1.32712440041 × 10²⁰. "
            "IAU nominal: 1.3271244 × 10²⁰. Difference is in the 8th digit, "
            "yielding ~10⁻⁸ relative change in rs — negligible."
        ),
        "finding": "Time coordinate choice shifts rs by < 10⁻⁵ km. No impact.",
        "breaks_proof": False,
    },
    {
        "question": "Do any authoritative sources cite a Schwarzschild radius outside [2.95, 2.96] km?",
        "verification_performed": (
            "Searched web: 'Schwarzschild radius Sun km value'. "
            "Wikipedia cites 'approximately 3.0 km' and '2.95 × 10³ m'. "
            "NASA SpaceMath cites ~3 km. No source gives a value outside "
            "the range [2.9, 3.0] km, and all precise computations give ~2.953 km."
        ),
        "finding": "No authoritative source contradicts the [2.95, 2.96] range.",
        "breaks_proof": False,
    },
]

# ============================================================================
# 11. VERDICT AND STRUCTURED OUTPUT
# ============================================================================
if __name__ == "__main__":
    any_unverified = any(
        cr["status"] != "verified" for cr in citation_results.values()
    )

    if claim_holds and not any_unverified:
        verdict = "PROVED"
    elif claim_holds and any_unverified:
        verdict = "PROVED (with unverified citations)"
    elif not claim_holds and not any_unverified:
        verdict = "DISPROVED"
    elif not claim_holds and any_unverified:
        verdict = "DISPROVED (with unverified citations)"
    else:
        verdict = "UNDETERMINED"

    FACT_REGISTRY["A1"]["method"] = "rs = 2 * G * (GM☉/G) / c² (G and M separate)"
    FACT_REGISTRY["A1"]["result"] = f"{rs_primary_km:.6f} km"
    FACT_REGISTRY["A2"]["method"] = "rs = 2 * GM☉ / c² (direct, G cancels)"
    FACT_REGISTRY["A2"]["result"] = f"{rs_crosscheck_km:.6f} km"

    citation_detail = build_citation_detail(FACT_REGISTRY, citation_results, empirical_facts)

    extractions = {
        "B1_G": {
            "value": str(G),
            "value_in_quote": True,
            "quote_snippet": f"{G_mantissa_str} x 10^{G_exponent_str}",
        },
        "B2_c": {
            "value": str(c),
            "value_in_quote": True,
            "quote_snippet": c_str,
        },
        "B3_GM_sun": {
            "value": str(GM_sun_iau),
            "value_in_quote": True,
            "quote_snippet": f"{GM_mantissa_str} x 10^20",
        },
        "B4_GM_sun_tcg": {
            "value": str(GM_sun_wiki),
            "value_in_quote": True,
            "quote_snippet": f"{GM_wiki_str} x 10^20",
        },
    }

    data_value_verification = {
        "B1": {k: v for k, v in dv_nist_G.items()},
        "B2": {k: v for k, v in dv_nist_c.items()},
        "B3": {k: v for k, v in dv_iau.items()},
        "B4": {k: v for k, v in dv_wiki.items()},
    }

    summary = {
        "fact_registry": {
            fid: {k: v for k, v in info.items()}
            for fid, info in FACT_REGISTRY.items()
        },
        "claim_formal": CLAIM_FORMAL,
        "claim_natural": CLAIM_NATURAL,
        "citations": citation_detail,
        "extractions": extractions,
        "data_value_verification": data_value_verification,
        "cross_checks": [
            {
                "description": "GM☉ IAU nominal vs Wikipedia TCG",
                "values_compared": [str(GM_sun_iau), str(GM_sun_wiki)],
                "agreement": True,
                "tolerance": "1e-5 relative",
            },
            {
                "description": "rs primary (G×M) vs direct (GM☉/c²)",
                "values_compared": [f"{rs_primary_km:.10f}", f"{rs_crosscheck_km:.10f}"],
                "agreement": True,
                "tolerance": "1e-10 km absolute",
            },
            {
                "description": "rs IAU nominal GM☉ vs Wikipedia GM☉",
                "values_compared": [f"{rs_crosscheck_km:.6f}", f"{rs_wiki_km:.6f}"],
                "agreement": True,
                "tolerance": "1e-5 km absolute",
            },
        ],
        "adversarial_checks": adversarial_checks,
        "verdict": verdict,
        "key_results": {
            "rs_primary_km": rs_primary_km,
            "rs_crosscheck_km": rs_crosscheck_km,
            "rs_wiki_km": rs_wiki_km,
            "threshold_lower": CLAIM_FORMAL["threshold_lower"],
            "threshold_upper": CLAIM_FORMAL["threshold_upper"],
            "lower_holds": lower_holds,
            "upper_holds": upper_holds,
            "claim_holds": claim_holds,
        },
        "generator": {
            "name": "proof-engine",
            "version": open(os.path.join(PROOF_ENGINE_ROOT, "VERSION")).read().strip(),
            "repo": "https://github.com/yaniv-golan/proof-engine",
            "generated_at": date.today().isoformat(),
        },
    }

    print(f"\n=== VERDICT: {verdict} ===")
    print(f"\n=== PROOF SUMMARY (JSON) ===")
    print(json.dumps(summary, indent=2, default=str))

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