Hilgenberg-OC: Science Contrarian review (Step 2)

Reviewer: Science Contrarian (judges by experimental evidence; builds the strongest honest case; examines how the claims were rejected). Tags: [read] = the folder document (Scalera and Braun 2003, extracted text and the Step 1b deep read); [web] = Internet source with URL; [memory] = recalled, with confidence; [calculation] = my arithmetic.

Source gap (repeated from claims.md). The folder holds one secondary document, written by Earth-expansion advocates (Scalera and Braun 2003). None of Hilgenberg's own works are in the folder. The Investigator found his 1933 book Vom wachsenden Erdball online (archive.org, read in part) and a library copy of the 1931 booklet exists (Met Office Library); I did not read either myself, so everything below about the 1933 book rests on the Investigator's notes, which I checked for arithmetic only. His 1931 and 1939 flow experiments, the 1933 Magnus reports and the 1965 paper (source of 4590 km) are unread by anyone in this review. Where a conclusion rests on [memory] or on the Investigator's reading alone, I say so.

1. What the evidence is, in one page

• Hilgenberg (1896-1976) was a trained electrical engineer who did oil-prospecting geophysics in Texas and New Mexico for four years, then worked at TH Berlin. He published in peer-reviewed venues in the 1960s (Geologische Rundschau 1965, Neues Jahrbuch, Geofisica Pura e Applicata, a 1963 Hobart symposium) [read: p.16-17]. So the geology was published, not blocked. The ether-gravity work was self-published (1929, 1931, 1939 booklets; the 1933 book carries his own imprint, printed by Gießmann & Bartsch [web: https://archive.org/details/Hilgenberg1933, via Investigator]).
• The physics has two layers that must be judged separately: (i) a gravity picture (masses as sinks of an ether flow) with an unexplained conversion of ether into matter; (ii) a geological claim (the Earth was much smaller and has grown). The second layer is the one that makes numerical predictions, and it is the one that has been tested.

2. Claim-by-claim review

Verdict scale from prompt.txt. Claim numbers follow claims.md.

Claim 1. Gravity is the accelerated flow of space (a Cartesian ether) towards massive bodies, each a sink.

a. Mathematics. The folder document has no equations [read: whole text]. In the 1933 book he argues from the relativity of motion and the equality of heavy and inertial mass to ether flowing into matter; two sinks attract, two sources attract, a sink and a source repel [web: archive.org Hilgenberg1933 scan n20, via Investigator]. No force law is derived in anything read. Here is the strongest honest case: a flow picture can reproduce Newtonian gravity exactly. If space flows radially inward at the free-fall speed v(r) = sqrt(2GM/r), a test body at rest in the flow accelerates at (v.grad)v = -GM/r^2 [calculation, standard]. For Earth's surface, v = sqrt(2 x 6.674e-11 x 5.972e24 / 6.371e6) = 11.19 km/s [calculation], the escape speed. This "river model" is a known, respectable reformulation: general relativity in Painlevé-Gullstrand coordinates is flat space with just such a flow, reaching the speed of light at a black-hole horizon (Hamilton and Lisle, "The river model of black holes", Am. J. Phys. 2008) [memory, high confidence on existence of the model]. So Hilgenberg's idea that gravity "is" accelerated flow of space is not mathematically absurd; as a coordinate description it is equivalent to the standard one. It becomes a distinct physical theory only when the flow is a real material ether that is consumed, and then it needs a flux, density and conversion law that nobody in the record supplies (the folder document: "No numbers" [read]; Scalera's 2021 abstract tries a first estimate [web: https://www.earth-prints.org/handle/2122/14738, via Investigator; Scalera is an interested party]). Internal consistency check: nothing contradictory is shown, because nothing is quantified. (The sign rules of sink and source attraction match the 19th-century Bjerknes pulsating-sphere analogy [memory, medium confidence; Investigator flagged it as unverified. Not checked by me: web budget went to the numbers that decide verdicts].)

b. Experiments. A material ether with a preferred frame faces the null results of Michelson-Morley-type experiments (modern cavity experiments are null at the 1e-17 level) [memory, high confidence]. Hilgenberg began by rejecting relativity and citing Miller's ether-drift result; the authors themselves call that "flawed by spurious effects, such as Miller's" [read: p.7]; the 1974 stance had become more accepting of relativity [read: p.7]. A flow ether that is only a coordinate description of GR makes no such conflict, which is the form the authors favour [read: p.8, p.14]. The "equivalence principle" argument [read: p.8] is the authors' paraphrase and they call it "more solid than Einstein's"; that is their evaluation, not Hilgenberg's.

c. Tests. Hilgenberg's own sink/source flow experiments (1931 booklet pp.14-15; the 1939 booklet; the 1933 Magnus reports) were carried out at TH Berlin [read: p.9]. Nobody else is recorded as repeating them; the 1938 thesis built on them was rejected (see section 4). I could not find any neutral, controlled test that asks the actual gravitational question (does a real flowing medium reproduce 1/r^2 attraction between macroscopic bodies, and what does it do to orbits?). Fluid sink analogies show attraction between sinks, which is real hydrodynamics [web: Investigator, 1933 book]; but a bath-tub analogy is not a test of gravity.

d. If true. Gravity would be mediated by a real, consumable medium; the energy budget of the consumption would need a home (see claim 2); Lorentz invariance would have to survive as an emergent symmetry.

Verdict: Not testable as stated (as a flow reformulation with no new physics: Plausible, untested in the sense that it can be made mathematically equivalent to known theory; as a material ether with ether-to-matter conversion: Never properly tested, because no quantitative law was ever derived to test). Was it dismissed without testing? On the record found, the 1938 thesis rejection was a theoretical dismissal (conflict with relativity) of experiments that were not independently repeated: dismissed without independent testing, with the caveat that the record is secondary.

Claim 2. Inflowing ether is converted inside planets into matter, so the Earth gains mass exponentially.

a. Maths. No rate in the folder document [read: p.9]. The 1933 book gives one (Investigator, from page image): V' = V e^(mu t), V/V' = 0.6^3 = 0.216, t = 1 Gyr = 3e16 s, so mu = ln(4.63)/3e16 = 5.1e-17 per second [calculation, agrees with Investigator]. The printed unit "g/sec" is a unit error by the inventor (it is a pure rate per second, grams per gram per second); worth recording because the reviewer must hold the inventor to the same standard as the critics. He flags the constant-density assumption as simplifying and "not true" himself [web, via Investigator]. Consequences of his own law [calculation]: - mu = 5.1e-17 /s = 1.61e-9 per year. Present mass gain mu x M = 1.61e-9 x 5.97e24 kg = 9.6e15 kg per year, about 3.0e8 kg per second. - Required ether flux at 100% efficiency through the surface at the escape speed (4 pi R^2 v = 5.7e18 m^3/s) gives an implied ether mass density of about 5e-11 kg/m^3 if every kilogram inflowing were converted [calculation; a lower bound on the needed density]. - Energy equivalent of the created mass: 3.0e8 kg/s x c^2 = 2.7e25 W. That is about 7% of the Sun's luminosity (3.8e26 W) [memory, high] and some 500,000 times the Earth's total heat loss (about 4.7e13 W) [memory, high]. This is not automatically a contradiction (the energy would come from the ether), but the ether then holds energy at a density that nothing has detected. Hilgenberg predicted the Earth's own temperature rises with mass growth [web: Investigator, 1933 book scan n21]; the energy flow he implies is not seen in the heat flow. - Mass conservation: the objection raised in 2001 by G. Bruhn (TU Darmstadt, mathematics) that expansion "massively violates the law of conservation of mass", and that meteorite input is "far too small" [web: https://web.archive.org/web/20021223154811/http://www.tu-berlin.de/presse/tui/01mai/hilgenb_lb.htm, via Investigator]. Check: meteoritic infall is of order 4e7 kg/year [memory, medium confidence], about 2e8 times smaller than 9.6e15 kg/yr [calculation]. Hilgenberg did not claim meteorites; his claim is creation, which is not a conservation violation if the ether is the source, only an unobserved conversion process, which the inventor himself calls unexplained [read: p.8; web: Investigator]. Bruhn's point stands against closed-system mass conservation and does not address an open-system ether. - Orbital dynamics: Earth's gravitational parameter would grow by 1.6e-9 per year. Lunar laser ranging limits the fractional rate of change of GM-type parameters to about 1e-13 per year (Ġ/G = (7.1 ± 7.6) x 10^-14 per year in a recent analysis) [web: https://arxiv.org/pdf/gr-qc/0412049 and the search results of 2026-10-06; limits on G-dot, which bound the same orbital quantity]. If the new mass gravitates like ordinary mass, this is about four orders of magnitude too large. The caveat: LLR analyses assume a specific parametrisation (G varies), not mass growth with momentum from an inflowing ether, and I did not find an analysis that treats Hilgenberg's model. So this is a strong constraint by calculation but not a direct test of his model.

b. Experiments. Radius growth is tested directly (see claim 3). The 1978 McElhinny, Taylor and Stevenson analysis of paleomagnetic data limited Earth expansion over 400 Myr to under 0.8% of the radius, and limited Mercury's and Moon's expansion too [web: https://www.nature.com/articles/271316a0]. A lunar surface static for 4 Gyr is a second planetary check if the mechanism is cosmological ("a cosmological agent that affected all heavenly bodies" [read: p.6]).

c. Tested? The mass-creation hypothesis has never been tested directly in the laboratory or by any measurement of the Earth's mass; its geological consequence has (claim 3). Replicated: no replication of the ether conversion exists. Geoneutrino results are offered by Scalera as "corroboration" [web: Earth-Prints abstract, via Investigator]; this is the interested party's characterisation, no analysis was found linking measured geoneutrino fluxes to a mass-creation rate.

d. If true: conservation of energy and baryon number (or at least of matter number) would hold only for the larger system including the ether; particle physics would need a vacuum-to-matter conversion process; cosmology would need a drain on vacuum energy.

Verdict: Never properly tested in its own terms (no mechanism, no neutral measurement); Refuted by calculation / Tested, not supported in its quantitative 1933 form (a mass gain of 1.6e-9 per year is excluded by space geodesy and orbital dynamics, see claim 3). Split: strong form (exponential growth at the 1933 rate) Tested, not supported; weak form (some unobserved creation at a rate far below geodetic sensitivity) Not testable as stated.

Claim 3. The Earth's radius nearly doubled since the Paleozoic (60%; 4590 km; 4 mm/yr).

a. Maths. The folder document's three numbers do not agree as printed [read: p.7, 10, 13; I confirmed the passages in the text: line "an earth 60% per cent of its present size", caption "radius of 4590 km", "4 millimetres per year"]. The Investigator's reading of the 1933 book resolves part of this: the 0.6 is a diameter ratio (0.62-0.65) of a shelf sphere he built by cutting and pasting, not a time-dated radius. My own computations [calculation] show what each pair of numbers implies: - 1933 law with his time base (1 Gyr): present radius growth dR/dt = R mu / 3 = 6.371e6 m x 1.61e-9 / 3 = 3.4 mm per year. So the 4 mm/yr is the right order for a present-day rate under the 1933 exponential law. This corrects a mild over-reading in Step 1 (see section 3). - The same law gives a Permian (250 Myr) radius of 6371 x exp(-1.61e-9 x 2.5e8 / 3) = 5570 km, not 4590 km. A radius of 4590 km at 250 Ma, with exponential growth, implies a present growth rate of about 8 mm per year. So the 1965 radius history (4590 km) and the 1933 constant (about 3.4 mm/yr) are not the same model. Whether the 1965 paper uses a different time scale or a different law is unknown without that paper. - If the Paleozoic start is taken as about 540 Ma [memory, high confidence] rather than his 1 Gyr (taken from Born's radioactive dating in 1933), the same 0.6 ratio implies mu = 2.8e-9 per year and a present rate of 6.0 mm per year [calculation]. None of this makes the proposal internally inconsistent; it shows the numbers belong to different constructions and the record has not reconciled them.

b. Experiments. The key tests, all of them independent of the ether question: - Space geodesy: Wu et al. (2011), combining SLR, VLBI, GPS and DORIS, found the mean radius of the Earth is not changing within 0.2 mm per year (1 sigma) [web: https://www.sciencedaily.com/releases/2011/08/110817120527.htm and https://www.jpl.nasa.gov/news/nasa-research-confirms-its-a-small-world-after-all/; the search result states the 0.2 mm/yr figure]. His own 1933 law predicts 3.4-6 mm per year, 17 to 30 times that bound [calculation]. This is a direct, quantitative disagreement in the one regime where an exponential law is at its most extreme (growth is fastest now). Expansion advocates can respond that expansion might be episodic or that the reference-frame origin cannot detect a very slow signal; but for a smooth law, as written by Hilgenberg, the test is decisive. The authors of the folder document do not discuss it (it postdates their 2003 text; the 1978 paper predates it and is not cited either [read: p.16-18]). - Paleomagnetism: McElhinny, Taylor and Stevenson (1978) limited the radius increase over 400 Myr to under 0.8% [web: https://www.nature.com/articles/271316a0]. Hilgenberg's own 1962-65 papers pioneered using paleopoles on variable-radius globes [read: p.12-13], which makes this the same kind of evidence he used. Caveat: those estimates rely on Pangaea-type reconstructions and the Earth's recorded paleolatitudes; Carey and later advocates (Maxlow, Scalera) dispute the reconstruction assumptions; I did not find a comparison of the dispute's merits in the record. - Ocean floor age: oceanic crust is nowhere older than about 180 Ma [memory, high confidence]; expansionists read this as consistent with growth; mainstream tectonics reads it as recycling by subduction. The folder authors concede that Hilgenberg's Pacific reconstruction "is not in agreement with the most up-to-date paleomagnetic data" [read: p.11]. - Rotation: Hilgenberg predicted that the spin speeds up and the days shorten with growth [web: Investigator, 1933 book scan n21]. Devonian corals show about 400 daily growth lines per year, i.e. days of about 22 hours, so days were shorter in the past, consistent with tidal braking and the opposite direction from his prediction [web: https://www.priweb.org/blog-post/john-wells-and-coral-geochronometry; https://scienceblog.com/t-coral-growth-rings-400-days-year/]. The authors themselves concede that planets tend to synchronous rotation [read: p.10]. - Geometric fit: on a sphere of 0.62 of the diameter the continental shelves close up with only two cuts (Mackenzie-Florida shear and an Alaska line) [web: Investigator]. Fits of continents on a smaller sphere are not a proof of expansion because the shelf area was an input (35% of the surface, from Wegener and Born) and cuts are allowed; the equally good fit on today's sphere (Bullard-type fits) is the mainstream alternative [memory, medium confidence]. The geometry is therefore an observation to be explained, not a discriminating test.

c. Tested? By whom: space geodesy (Wu et al. 2011), paleomagnetism (McElhinny et al. 1978); both by independent geophysicists. Replicated: the geodetic bound is based on four techniques and later reference-frame work is consistent [memory, medium confidence; not checked]. Was Hilgenberg's claim rejected soundly? The tests were not run to reject Hilgenberg specifically; they test expansion in general and apply to his law. The 1974 open letter to Wilson, Beloussov and van Bemmelen drew no reported reply [read: p.13-14], so a direct response by the authorities he addressed is missing from the record.

d. If true: the plate-tectonic accounting of seafloor creation without destruction would have to replace subduction, the lithosphere would have to be stretched over a growing sphere (rifts and grabens), and the geodetic bound would have to be explained away.

Verdict: Tested, not supported (strong form: smooth exponential growth, 4-6 mm/yr now, radius near 60-72% in the Paleozoic). Weak form (a small, much slower expansion of under about 0.8% over 400 Myr): Plausible, untested at that level, in the sense that existing limits do not exclude zero-to-small change, and it is not what Hilgenberg claimed.

Claim 4. Ether flow to the Sun plus an "inverted Magnus effect" spins planets up until a ring detaches.

a. Maths. None given [read: p.9-10]. b. Experiments. The lab part has a real counterpart: a negative (reverse) Magnus force on a rotating sphere or cylinder occurs at Reynolds numbers in the critical regime, with the boundary layer turning turbulent on the advancing side and moving the separation point back [web: https://arxiv.org/pdf/2302.11260 and other results from the 2026-10-06 search; Re about 1e5]. Hilgenberg's 1933 reports claim an inversion; whether his effect is this Reynolds-number effect or the sink/source effect he describes is not determinable without his papers [read: p.9, p.16]. In fluid dynamics the reverse Magnus effect is established; his later priority (1933) over the modern literature cannot be judged from the record. [Memory, medium confidence: the reverse Magnus effect was already known in the 1920s-30s from Göttingen; not checked.] c. Tested. The planetary application: authors themselves "consider less valid today" the ring-expulsion cycle, citing tidal-friction synchronisation and no planet near the needed spin [read: page image p.10]. The coral record points the other way, as noted in claim 3. d. If true: planets would be expected to spin up, and rings would form from spun-up planets; observation shows the Earth's spin slowing.

Verdict: split. Lab effect (an inverted Magnus force exists in some flow regimes): Established, though Hilgenberg's own measurements are unread and unreplicated by name. Planetary spin-up and ring-expulsion: Historically superseded but instructive (the authors' own judgement), and Tested, not supported by the length-of-day record.

Claim 5. Continental outlines moved between smaller globes; paleopoles; explains trenches, rifts and Benioff zones without subduction.

a. Maths. The method (transposing outlines between spheres of different radius, equidistant azimuthal projection, paleopole directions on orthographic maps) is consistent as geometry; the authors note that different transformation laws (equal-area, equidistant, similar) give different pole dispersions and a distinct law is needed for paleopoles [read: p.11-13]. A mathematically legitimate and, for 1965, innovative technique ("For the first time, paleopoles were used on a variable-radius globe" [read: p.13], authors' claim). b. Experiments. Seismic tomography images cold, inclined slabs to about 700 km (and deeper) beneath trenches; the authors admit the data and say Hilgenberg's rising-dunite reading "might once again be appraised" if hot rising matter cools [read: p.11-12]. A sinking slab is the mainstream reading. Seafloor magnetic stripes and GPS plate motions are other mainstream evidence [memory, high confidence]. Hilgenberg could not know the 1960s-70s seafloor data fully, and his 1974 text is partly a reply to it, though the record has no reply. c. Tested by whom. Paleomagnetic radius (McElhinny 1978) and geodesy (Wu 2011) as in claim 3; tomography interpreted by mainstream seismologists. No neutral test comparing plate-tectonic and expansion reconstructions of the same data appears in the record. d. If true: subduction would be minor or absent; ocean floor would be older and more widely distributed than the 180 Ma limit implies.

Verdict: Tested, not supported for the version that denies subduction. The reconstruction technique itself and the observation of shelf fit: Plausible, untested as an alternative geometric description, and instructive.

Claim 6. The right question is expansion with or without new matter; the ether picture is analogous to and may converge with GR; ether inflow at c equals a black hole.

a. Maths. No equations in the document [read: p.13-15]. The black-hole statement has a real mathematical counterpart: the river model, where the inflow speed equals c at the horizon [memory, high confidence; see claim 1]. So "equivalent" in that narrow sense is not wrong. The Riemann story (setting ether energy density to zero, adding a fourth coordinate gives GR) is the authors' paraphrase and cannot be checked from anything read; the 1933 book already compares his picture with Riemann [web: Investigator]. b. Experiments. Black holes exist as astrophysical objects; the river model matches GR predictions by construction, so no experiment separates it from GR. c. Tested: the open letter drew no recorded reply [read: p.13-14]. d. If true: nothing new for GR; for ether conversion, see claim 2.

Verdict: Not testable as stated (the analogy to GR); the framing that expansion needs new matter is Tested, not supported at the level of claim 3.

3. Corrections to Step 1

1. claims.md claim 3 and facts.json read the "60%" as a Paleozoic size of the Earth. The Investigator's reading of the 1933 book shows it is a diameter ratio of Hilgenberg's own paper-on-globe construction (0.62-0.65), from which V/V' = 0.216 and mu about 5e-17 per second follows [calculation confirmed]. Keep the claim, but state "60% of present diameter in the 1933 shelf-sphere construction".
2. Step 1 (deep read section 2) says the 4 mm/yr is hard to read as a present-day rate under exponential growth with 4590 km. That is correct for the 4590 km figure but not for the 1933 law, which gives 3.4 mm/yr now [calculation]. So 4 mm/yr is consistent with the 1933 growth law as a present-day rate, and inconsistent with 4590 km at 250 Ma (which gives about 8 mm/yr). The inconsistency lies between two models (1933 and 1965), not within a single one, and remains open until the 1965 paper is read.
3. The folder document and facts.json give Gießmann & Bartsch as the publisher of the 1933 book. The title page says Verlag O. Hilgenberg, printed by Gießmann & Bartsch [web: https://archive.org/details/Hilgenberg1933, Investigator]. Minor.
4. claims.md says one effect was "completely proven" in the 1933 reports and that the reports were of the "inverted Magnus effect". The text does not say which effect was proven; the deep read correctly notes this link is an inference from titles [read: p.9]. claims.md claim 4 states it as fact and should be softened.
5. Step 1 treats the geometric statements and the ether statements as one package. They are separately testable, and the first tests (geodesy, paleomagnetism) do not depend on the ether. I have split verdicts accordingly.
6. The deep read marks the Penzias and Wilson date (1968) as the authors' date: the discovery was announced in 1965 [memory, high confidence]; also the open-letter addressees are surnames only. Both are fine as flagged. No error was found in the page citations I spot-checked (60%, 4590 km, 4 mm/yr, "less valid today", rejection of the thesis) against the extracted text.

4. How it was rejected: the record

• Thesis: Scalera and Braun [read: p.8]: "severe rejection of his thesis from the examination committee" on conflict with contemporary physics and with the dominant politics. German Wikipedia (tertiary): the first doctoral thesis, on sink and source flow experiments, was rejected in 1938 by the Faculty of Mechanical Engineering, mainly because his ether-gravity view conflicted with relativity [web: https://de.wikipedia.org/wiki/Ott_Christoph_Hilgenberg, via Investigator]. Thielmann (2015) and zillmer.com: submitted 1937, rejected [web: https://doi.org/10.1515/9783839406106-003, via Investigator]. Three accounts, none citing the faculty file; the referees and their reasons are not on record. So: documented in several secondary sources; not verified by a primary record; the TU Berlin University Archive doctoral file would settle it. Notably he later obtained a Dr.-Ing. (1948, TU Berlin) on fault structure, so the university did not exclude him permanently.
• NSDAP refusal: Scalera-Braun [read: p.7], German Wikipedia, and Jacob's 2001 article all trace to the same advocacy circle. It is evidence (a documented claim in three places) with no independent record yet; a personnel file would show it.
• Rejection by critics in 2001 (TU Berlin forum): Bruhn (mass conservation, tomography), Seiler ("gut-feeling" arguments), Thorweihe (no discussion in modern geoscience) [web: Investigator, TU intern reader responses]. These are opinions, partly sound (conservation, tomography) and partly sociological (Thorweihe notes absence of discussion, which is not an argument). The expert reply "Erdexpansion ad acta gelegt" (July 2001) has not been opened.
• Publication: not blocked. The 1960s papers appeared in Springer, Schweizerbart and Italian journals [read: p.16-17]; the 1974 monograph of 194 pages filled an entire issue of Geotektonische Forschungen. His 1967 TU Berlin talk, his workroom in the TU geological institute, the support of Quiring and Zeil, and the 2001 colloquium indicate institutional tolerance along with scientific non-acceptance. The authors' framing of isolation [read: p.6-7] is their own.
• Absence of evidence: (a) no independent repetition of the 1931/1939 sink-source flow experiments or the 1933 Magnus reports (competing explanations: the experiments were unremarkable fluid dynamics nobody needed to repeat; the link to gravity was never accepted; he published outside refereed venues; in wartime Germany little replication was possible. Decider: citations of the 1933 Z. Techn. Phys. paper and TU archive records). (b) no reply to the 1974 open letter (explanations: not answered, not preserved, or not sent; decider: Wilson/Beloussov/van Bemmelen correspondence archives). (c) A quantitative ether theory never appeared; Scalera's 2021 abstract is the first attempt found.

5. Strongest honest case, and what weakens it

For: (1) the flow description of gravity is mathematically respectable (river model) and contains the black-hole horizon at inflow speed c, a notable anticipation if one is generous; (2) Hilgenberg's variable-radius paleopole method was original and his work was published in refereed geology journals; (3) he made falsifiable numerical predictions (mu, temperature rise, days shortening) and invited readers to check the globe construction themselves, which is the right attitude; (4) the expansion question was open in the 1960s and the decisive paleomagnetic and geodetic limits arrived later (1978, 2011); (5) the reverse Magnus effect is real. Against: (1) the quantitative predictions fail: 3.4-6 mm/yr radius growth versus a 0.2 mm/yr geodetic bound; a mass growth four orders above LLR sensitivity; day length goes the wrong way; (2) no conversion mechanism or measurement; (3) inventor errors: a units slip ("g/sec"), a 1 Gyr time base twice the Cambrian age, an unreconciled 60%/4590 km/4 mm per year, an early reliance on Miller's ether drift which the authors call flawed; (4) the advocates' honour volume is an interested source, though it states its own reservations [read: p.10-11, 16].

6. Investigator's findings kept in the record

Hilgenberg's 1933 book online (archive.org; nuclearplanet.com, reproduction allowed by his daughter Helge, with J.M. Herndon, a rival model proponent, as host); the Met Office copy of the 1931 booklet; Yarkovsky 1888 as the same ether-inflow-and-conversion principle 45 years earlier; Krafft's The Ether and its Vortices (translated by Hilgenberg 1953); Pascual Jordan's decreasing-G expansion; Herndon's decompression model; the Bjerknes analogy (memory, unverified); Westphal's earlier sink/source experiments; Farrell's popular accounts of the 1959 vortex-ring atom (not read); the TU intern forum with named witnesses (Fiedler-Volmer, Oppermann) and critics; the 2001 colloquium and Scalera's four replica globes; the three accounts of the thesis rejection; Scalera's 2021 geoneutrino claim (interested party). None is dropped.

7. What would settle the open points

• A single obvious quantity: the 1965 Geologische Rundschau 55, 878-924 paper (radius history, time base). With it, the 1933 and 1965 rates can be checked against geodesy.
• TU Berlin University Archive: Promotionsakte 1937/38 and the personnel file for 1934-38.
• The 1931 and 1939 booklets and the 1933 Magnus reports: do the measurements show an inverted effect, at what Reynolds number, and could a flow experiment reproduce attraction?
• A calculation by the reader: dR/dt = R x mu/3 with mu = ln(1/0.216)/t for t = 1 Gyr and for t = 540 Myr, compared with 0.2 mm per year.