The Bell Frame-Drag Bench: The Drums and the Field

THE BELL FRAME-DRAG BENCH · JORJANI 3.4 × COOK CH. 20 × EVERITT ET AL. 2011
Two counter-rotating drums of a dense fill: what general relativity gives for the object the accounts describe
a spinning mass drags the inertial frames around it; a gyroscope nearby precesses at Ω
the ruler is the Earth's own dragging, measured by Gravity Probe B at 37.2 ± 7.2 mas/yr
the field, the calibration, the rim and the clocks are exact; the drums' sizes and the chamber are dials and staging
the accounts give the drums no spin, mass or size (the bell is nine to twelve feet tall); every one of those is a dial here
spin the drums · sweep the rate · read the clocks · find the threshold · open the file

Evidence

fact ⇄ what kind of claim · live

Jorjani: 'two counter-rotating drums', a 'Mercury-Thorium isotope', 'a supermassive vortex that distorts the space-time continuum', time 'at a different rate', a device 'chained down'. Cook, relaying the testimony: 'two cylinders in opposite directions', Xerum 525, a 30 m² tiled chamber, tests of a minute, personnel at 150 to 200 m; Marckus's 'thousandth of one percent'

the accounts' own words, with their authors and footnotes; nothing added

REPORTED

Gravity Probe B: frame dragging −37.2 ± 7.2 mas/yr (predicted −39.2), four gyroscopes, a 642 km polar orbit, 2004 to 2005. LAGEOS: 99 ± 5 percent of the prediction, ± 10 allowed

Everitt et al. 2011; Ciufolini and Pavlis 2004

MEASURED

Frame dragging in the weak field: Ω = (G/c²r³)[3(J·r̂)r̂ − J]; a ring's centre 4Gmω/(c²(Ro + Ri)); a shell's axis 2GIω/(c²z³). Van Stockum's exterior closes a timelike curve for ΩR/c > 1/2; Hawking's averaged weak energy condition

Lense and Thirring 1918 and Schiff 1960 as Everitt et al. cite them; Tajmar et al. 2007 eq. 4 and 5; Lobo 2007; Tipler 1974; Hawking 1992

ESTABLISHED

The Earth (mass, radius, I/MR², sidereal day), the Moon's mass, the densities of mercury, thorium and niobium, three steel yields

NASA fact sheets; element and strength tables

TABULATED

The field summed over the drums' mass current and its far field; the Earth calibration that returns 39.2 mas/yr; the rim speed and wall pressure; the clock offsets; van Stockum's radius and axis density

arithmetic on the formulas above; no constant fitted to any account

EXACT

The drums' radii, heights, fill and spin; the probe's distance; the chamber, the bell, the glow and the chains

the description gives none of them; shown as dials and staging

MODELLED

What the distance between the accounts and the numbers means

the question this bench leaves to you

READING

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